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Global Functionsthen use gloablly. I set up a class called L3Global in which I have a function as follows: Public Function SetDBConnect() Dim ConnStrL3Producer As String ConnStrL3Producer = "User ID=UID;Tag with column collation when possible=False;Data Source=" & Chr(34) & "a.b.c.d" & Chr(34) & ";Password=PWD;" ConnStrL3Producer = ConnStrL3Producer & "Initial Catalog=L3;Use Procedure for Prepare=1;Auto Translate=True;Persist Security Info=True;Provider=" ConnStrL3Producer = ConnStrL3Producer & Chr(34) & "SQLOLEDB.1" & Chr(34) & ";Workstation ID=AUM;Use Encryption for Data=False;Packet Size=4096" Dim ConnL3Producer As New OleDbConnection(ConnStrL3Producer) Return ConnL3Producer End Function Now I want to use this is all my forms (MDI). I set up Public L3G As New L3Global and then under the approporate button click I have: Dim ConnL3Producer As New OleDbConnection ConnL3Producer = L3G.SetDBConnect The problem is, do I have to setup an instance of L3Global in each form? That defeats the purpose, because each one opens a new connection. How can I use this connection object in all my forms but open it only once? Ideally I would like to move as much of the intialization (creating the OLEDBAdapter etc) to the global routine. Thanx for any suggestions. Well i would not recomend a global connection aproach in .Net
Because of the superb connection pool mechanism , you can now safely and without anny performance overhead create , use , and destroy especially the using statement is verry handy with this personally i would store the connection string in the config file regards Michel Show quoteHide quote "Anil Gupte" <anil-l***@icinema.com> schreef in bericht news:Ofv0ON0HHHA.1188@TK2MSFTNGP06.phx.gbl... >I am trying to set up a function that connects to the database that I can >then use gloablly. I set up a class called L3Global in which I have a >function as follows: > > Public Function SetDBConnect() > Dim ConnStrL3Producer As String > ConnStrL3Producer = "User ID=UID;Tag with column collation when > possible=False;Data Source=" & Chr(34) & "a.b.c.d" & Chr(34) & > ";Password=PWD;" > ConnStrL3Producer = ConnStrL3Producer & "Initial Catalog=L3;Use Procedure > for Prepare=1;Auto Translate=True;Persist Security Info=True;Provider=" > ConnStrL3Producer = ConnStrL3Producer & Chr(34) & "SQLOLEDB.1" & Chr(34) & > ";Workstation ID=AUM;Use Encryption for Data=False;Packet Size=4096" > Dim ConnL3Producer As New OleDbConnection(ConnStrL3Producer) > Return ConnL3Producer > End Function > > Now I want to use this is all my forms (MDI). I set up > Public L3G As New L3Global > > and then under the approporate button click I have: > Dim ConnL3Producer As New OleDbConnection > > ConnL3Producer = L3G.SetDBConnect > > The problem is, do I have to setup an instance of L3Global in each form? > That defeats the purpose, because each one opens a new connection. How > can I use this connection object in all my forms but open it only once? > Ideally I would like to move as much of the intialization (creating the > OLEDBAdapter etc) to the global routine. > > Thanx for any suggestions. > -- > Anil Gupte > www.keeninc.net > www.icinema.com > > Thanx for that tip, but please explain:
"...especially the using statement is verry handy with this" and also "...personally i would store the connection string in the config file" I am a newbie at .Net and last used VB five years ago for a few months. Show quoteHide quote "Michel Posseth [MCP]" <M***@posseth.com> wrote in message news:eqa5xv0HHHA.1280@TK2MSFTNGP04.phx.gbl... > > Well i would not recomend a global connection aproach in .Net > > Because of the superb connection pool mechanism , you can now safely and > without anny performance overhead create , use , and destroy > especially the using statement is verry handy with this > > personally i would store the connection string in the config file > > regards > > Michel > > > > "Anil Gupte" <anil-l***@icinema.com> schreef in bericht > news:Ofv0ON0HHHA.1188@TK2MSFTNGP06.phx.gbl... >>I am trying to set up a function that connects to the database that I can >>then use gloablly. I set up a class called L3Global in which I have a >>function as follows: >> >> Public Function SetDBConnect() >> Dim ConnStrL3Producer As String >> ConnStrL3Producer = "User ID=UID;Tag with column collation when >> possible=False;Data Source=" & Chr(34) & "a.b.c.d" & Chr(34) & >> ";Password=PWD;" >> ConnStrL3Producer = ConnStrL3Producer & "Initial Catalog=L3;Use Procedure >> for Prepare=1;Auto Translate=True;Persist Security Info=True;Provider=" >> ConnStrL3Producer = ConnStrL3Producer & Chr(34) & "SQLOLEDB.1" & Chr(34) >> & ";Workstation ID=AUM;Use Encryption for Data=False;Packet Size=4096" >> Dim ConnL3Producer As New OleDbConnection(ConnStrL3Producer) >> Return ConnL3Producer >> End Function >> >> Now I want to use this is all my forms (MDI). I set up >> Public L3G As New L3Global >> >> and then under the approporate button click I have: >> Dim ConnL3Producer As New OleDbConnection >> >> ConnL3Producer = L3G.SetDBConnect >> >> The problem is, do I have to setup an instance of L3Global in each form? >> That defeats the purpose, because each one opens a new connection. How >> can I use this connection object in all my forms but open it only once? >> Ideally I would like to move as much of the intialization (creating the >> OLEDBAdapter etc) to the global routine. >> >> Thanx for any suggestions. >> -- >> Anil Gupte >> www.keeninc.net >> www.icinema.com >> >> > > I can't know if you have but if you haven't heard of design patterns I think
you should spend a little time reading about them. Here is an overview: http://en.wikipedia.org/wiki/Design_pattern_(computer_science) Particularly you are describing a Singleton pattern (there is code here in C# which you can take a look at) http://en.wikipedia.org/wiki/Singleton_pattern Show quoteHide quote "Anil Gupte" <anil-l***@icinema.com> wrote in message news:Ofv0ON0HHHA.1188@TK2MSFTNGP06.phx.gbl... >I am trying to set up a function that connects to the database that I can >then use gloablly. I set up a class called L3Global in which I have a >function as follows: > > Public Function SetDBConnect() > Dim ConnStrL3Producer As String > ConnStrL3Producer = "User ID=UID;Tag with column collation when > possible=False;Data Source=" & Chr(34) & "a.b.c.d" & Chr(34) & > ";Password=PWD;" > ConnStrL3Producer = ConnStrL3Producer & "Initial Catalog=L3;Use Procedure > for Prepare=1;Auto Translate=True;Persist Security Info=True;Provider=" > ConnStrL3Producer = ConnStrL3Producer & Chr(34) & "SQLOLEDB.1" & Chr(34) & > ";Workstation ID=AUM;Use Encryption for Data=False;Packet Size=4096" > Dim ConnL3Producer As New OleDbConnection(ConnStrL3Producer) > Return ConnL3Producer > End Function > > Now I want to use this is all my forms (MDI). I set up > Public L3G As New L3Global > > and then under the approporate button click I have: > Dim ConnL3Producer As New OleDbConnection > > ConnL3Producer = L3G.SetDBConnect > > The problem is, do I have to setup an instance of L3Global in each form? > That defeats the purpose, because each one opens a new connection. How > can I use this connection object in all my forms but open it only once? > Ideally I would like to move as much of the intialization (creating the > OLEDBAdapter etc) to the global routine. > > Thanx for any suggestions. > -- > Anil Gupte > www.keeninc.net > www.icinema.com > > Hmm, I must be in a parallel universe. Just kidding of course, but I did
not follow most of what I read on those links, and I am not that much of a programmer (nor do I ever hope to be). I am just building a prototype of software that I want real programmers to write. Anyway, if you have seen specific tutorials relating to this, please do let me know. Anyway Thanx, Show quoteHide quote "Tom Leylan" <gee@iamtiredofspam.com> wrote in message news:eQJth94HHHA.420@TK2MSFTNGP06.phx.gbl... >I can't know if you have but if you haven't heard of design patterns I >think you should spend a little time reading about them. Here is an >overview: http://en.wikipedia.org/wiki/Design_pattern_(computer_science) > > Particularly you are describing a Singleton pattern (there is code here in > C# which you can take a look at) > http://en.wikipedia.org/wiki/Singleton_pattern > > > "Anil Gupte" <anil-l***@icinema.com> wrote in message > news:Ofv0ON0HHHA.1188@TK2MSFTNGP06.phx.gbl... >>I am trying to set up a function that connects to the database that I can >>then use gloablly. I set up a class called L3Global in which I have a >>function as follows: >> >> Public Function SetDBConnect() >> Dim ConnStrL3Producer As String >> ConnStrL3Producer = "User ID=UID;Tag with column collation when >> possible=False;Data Source=" & Chr(34) & "a.b.c.d" & Chr(34) & >> ";Password=PWD;" >> ConnStrL3Producer = ConnStrL3Producer & "Initial Catalog=L3;Use Procedure >> for Prepare=1;Auto Translate=True;Persist Security Info=True;Provider=" >> ConnStrL3Producer = ConnStrL3Producer & Chr(34) & "SQLOLEDB.1" & Chr(34) >> & ";Workstation ID=AUM;Use Encryption for Data=False;Packet Size=4096" >> Dim ConnL3Producer As New OleDbConnection(ConnStrL3Producer) >> Return ConnL3Producer >> End Function >> >> Now I want to use this is all my forms (MDI). I set up >> Public L3G As New L3Global >> >> and then under the approporate button click I have: >> Dim ConnL3Producer As New OleDbConnection >> >> ConnL3Producer = L3G.SetDBConnect >> >> The problem is, do I have to setup an instance of L3Global in each form? >> That defeats the purpose, because each one opens a new connection. How >> can I use this connection object in all my forms but open it only once? >> Ideally I would like to move as much of the intialization (creating the >> OLEDBAdapter etc) to the global routine. >> >> Thanx for any suggestions. >> -- >> Anil Gupte >> www.keeninc.net >> www.icinema.com >> >> > > A fairly common problem developers run into is having non-developers explain
how to develop applications :-) I'll suggest that you ordinarily wouldn't need to explain to a developer your preference for a single connection, globally accessible from anywhere in the application. The developer(s) can figure out a) if that is a good idea and b) how best to implement it. Design patterns have been around for a very long time but (more or less) recently were given names and categorized. There are many books and thousands of articles on the subject but in a nutshell most of what developers do isn't "new" and whether we are instantiating a customer, inventory item, baseball score or anything else the process is the same. I don't mean that the code exists I mean the "pattern" that the code will follow exists. Your house may look completely different from another but it will have a foundation, walls and a roof, those are givens. Bottom line is when you have some time consider reading an introduction articles on design patterns. If it does nothing else you may have the "aha" moment when you find something you've been trying to explain to a developer actually has a name and everybody already knows about it. Also if you create a singleton class your "I don't want two instances" problem goes away. There may be a dozen other tricky ways to do it but ask yourself what is the advantage to not using a proven design that everybody else is using? Take care, Tom Show quoteHide quote "Anil Gupte" <anil-l***@icinema.com> wrote in message news:%23pT5Xg5HHHA.1276@TK2MSFTNGP04.phx.gbl... > Hmm, I must be in a parallel universe. Just kidding of course, but I did > not follow most of what I read on those links, and I am not that much of a > programmer (nor do I ever hope to be). I am just building a prototype of > software that I want real programmers to write. > > Anyway, if you have seen specific tutorials relating to this, please do > let me know. > > Anyway Thanx, > -- > Anil Gupte > www.keeninc.net > www.icinema.com > > "Tom Leylan" <gee@iamtiredofspam.com> wrote in message > news:eQJth94HHHA.420@TK2MSFTNGP06.phx.gbl... >>I can't know if you have but if you haven't heard of design patterns I >>think you should spend a little time reading about them. Here is an >>overview: http://en.wikipedia.org/wiki/Design_pattern_(computer_science) >> >> Particularly you are describing a Singleton pattern (there is code here >> in C# which you can take a look at) >> http://en.wikipedia.org/wiki/Singleton_pattern >> >> >> "Anil Gupte" <anil-l***@icinema.com> wrote in message >> news:Ofv0ON0HHHA.1188@TK2MSFTNGP06.phx.gbl... >>>I am trying to set up a function that connects to the database that I can >>>then use gloablly. I set up a class called L3Global in which I have a >>>function as follows: >>> >>> Public Function SetDBConnect() >>> Dim ConnStrL3Producer As String >>> ConnStrL3Producer = "User ID=UID;Tag with column collation when >>> possible=False;Data Source=" & Chr(34) & "a.b.c.d" & Chr(34) & >>> ";Password=PWD;" >>> ConnStrL3Producer = ConnStrL3Producer & "Initial Catalog=L3;Use >>> Procedure for Prepare=1;Auto Translate=True;Persist Security >>> Info=True;Provider=" >>> ConnStrL3Producer = ConnStrL3Producer & Chr(34) & "SQLOLEDB.1" & Chr(34) >>> & ";Workstation ID=AUM;Use Encryption for Data=False;Packet Size=4096" >>> Dim ConnL3Producer As New OleDbConnection(ConnStrL3Producer) >>> Return ConnL3Producer >>> End Function >>> >>> Now I want to use this is all my forms (MDI). I set up >>> Public L3G As New L3Global >>> >>> and then under the approporate button click I have: >>> Dim ConnL3Producer As New OleDbConnection >>> >>> ConnL3Producer = L3G.SetDBConnect >>> >>> The problem is, do I have to setup an instance of L3Global in each form? >>> That defeats the purpose, because each one opens a new connection. How >>> can I use this connection object in all my forms but open it only once? >>> Ideally I would like to move as much of the intialization (creating the >>> OLEDBAdapter etc) to the global routine. >>> >>> Thanx for any suggestions. >>> -- >>> Anil Gupte >>> www.keeninc.net >>> www.icinema.com >>> >>> >> >> > > Because you are not that much of a programmer (nor do you ever hope to be),
I strongly suggest that you do NOT build a prototype of software that you want real programmers to write. Instead, write a specification document that describes, at a fairly high level, the purpose of the software, what the 'inputs' are, what the 'outputs' must be and what the expected outcomes are. Include details of business rules and pictures of what various forms and reports should look like. If there are any aspects of the specification that are immutable then make those aspect clear and unambiguous. Also include details of what technologies may or may not be used. You will find that a real programmer, when presented with such a document, will have no problems figuring out the best way to implement the design and will be more productive than having to work from a protoype developed by someone who doesn't really know what they are doing. Show quoteHide quote "Anil Gupte" <anil-l***@icinema.com> wrote in message news:%23pT5Xg5HHHA.1276@TK2MSFTNGP04.phx.gbl... > Hmm, I must be in a parallel universe. Just kidding of course, but I did > not follow most of what I read on those links, and I am not that much of a > programmer (nor do I ever hope to be). I am just building a prototype of > software that I want real programmers to write. > > Anyway, if you have seen specific tutorials relating to this, please do > let me know. > > Anyway Thanx, > -- > Anil Gupte > www.keeninc.net > www.icinema.com > > "Tom Leylan" <gee@iamtiredofspam.com> wrote in message > news:eQJth94HHHA.420@TK2MSFTNGP06.phx.gbl... >>I can't know if you have but if you haven't heard of design patterns I >>think you should spend a little time reading about them. Here is an >>overview: http://en.wikipedia.org/wiki/Design_pattern_(computer_science) >> >> Particularly you are describing a Singleton pattern (there is code here >> in C# which you can take a look at) >> http://en.wikipedia.org/wiki/Singleton_pattern >> >> >> "Anil Gupte" <anil-l***@icinema.com> wrote in message >> news:Ofv0ON0HHHA.1188@TK2MSFTNGP06.phx.gbl... >>>I am trying to set up a function that connects to the database that I can >>>then use gloablly. I set up a class called L3Global in which I have a >>>function as follows: >>> >>> Public Function SetDBConnect() >>> Dim ConnStrL3Producer As String >>> ConnStrL3Producer = "User ID=UID;Tag with column collation when >>> possible=False;Data Source=" & Chr(34) & "a.b.c.d" & Chr(34) & >>> ";Password=PWD;" >>> ConnStrL3Producer = ConnStrL3Producer & "Initial Catalog=L3;Use >>> Procedure for Prepare=1;Auto Translate=True;Persist Security >>> Info=True;Provider=" >>> ConnStrL3Producer = ConnStrL3Producer & Chr(34) & "SQLOLEDB.1" & Chr(34) >>> & ";Workstation ID=AUM;Use Encryption for Data=False;Packet Size=4096" >>> Dim ConnL3Producer As New OleDbConnection(ConnStrL3Producer) >>> Return ConnL3Producer >>> End Function >>> >>> Now I want to use this is all my forms (MDI). I set up >>> Public L3G As New L3Global >>> >>> and then under the approporate button click I have: >>> Dim ConnL3Producer As New OleDbConnection >>> >>> ConnL3Producer = L3G.SetDBConnect >>> >>> The problem is, do I have to setup an instance of L3Global in each form? >>> That defeats the purpose, because each one opens a new connection. How >>> can I use this connection object in all my forms but open it only once? >>> Ideally I would like to move as much of the intialization (creating the >>> OLEDBAdapter etc) to the global routine. >>> >>> Thanx for any suggestions. >>> -- >>> Anil Gupte >>> www.keeninc.net >>> www.icinema.com >>> >>> >> >> > > Anil Gupte wrote:
> I am trying to set up a function that connects to the database that I can <snip>> then use gloablly. I set up a class called L3Global in which I have a > function as follows: > Public Function SetDBConnect() > Now I want to use this is all my forms (MDI). I set up <snip>> Public L3G As New L3Global > > and then under the approporate button click I have: > Dim ConnL3Producer As New OleDbConnection > > ConnL3Producer = L3G.SetDBConnect > > The problem is, do I have to setup an instance of L3Global in each form? > That defeats the purpose, because each one opens a new connection. How can > I use this connection object in all my forms but open it only once? Ideally > I would like to move as much of the intialization (creating the OLEDBAdapter > etc) to the global routine. I guess you can declare a Module, instead of a class: <aircode> Module L3Global Private mConnection As OleDBConnection Public Function ConnectDB() As OleDBConnection If mConnection Is Nothing Then Dim ConText As String = "Your connection string" mCOnnection = New OleDBConnectins(ConText) End If Return mConnection End Function End Module </aircode> And then, in your Forms you'd have: Dim ConnL3Producer _ As OleDbConnection = L3Global.ConnectDB() Improvise over that. Regards, Branco. Thanx, that will get me started. Do you happen to know any place where I
can read more about when to use a Module and when to use a class? Thanx again, Show quoteHide quote "Branco Medeiros" <branco.medei***@gmail.com> wrote in message news:1166131605.256508.207250@n67g2000cwd.googlegroups.com... > Anil Gupte wrote: >> I am trying to set up a function that connects to the database that I can >> then use gloablly. I set up a class called L3Global in which I have a >> function as follows: > >> Public Function SetDBConnect() > <snip> > >> Now I want to use this is all my forms (MDI). I set up >> Public L3G As New L3Global >> >> and then under the approporate button click I have: >> Dim ConnL3Producer As New OleDbConnection >> >> ConnL3Producer = L3G.SetDBConnect >> >> The problem is, do I have to setup an instance of L3Global in each form? >> That defeats the purpose, because each one opens a new connection. How >> can >> I use this connection object in all my forms but open it only once? >> Ideally >> I would like to move as much of the intialization (creating the >> OLEDBAdapter >> etc) to the global routine. > <snip> > > I guess you can declare a Module, instead of a class: > > <aircode> > Module L3Global > Private mConnection As OleDBConnection > > Public Function ConnectDB() As OleDBConnection > If mConnection Is Nothing Then > Dim ConText As String = "Your connection string" > mCOnnection = New OleDBConnectins(ConText) > End If > Return mConnection > End Function > End Module > </aircode> > > And then, in your Forms you'd have: > > Dim ConnL3Producer _ > As OleDbConnection = L3Global.ConnectDB() > > Improvise over that. > > Regards, > > Branco. > Anil: Yes you can read it right here :-) Never use a module!
VB.Net is an object-oriented language and by definition that should lead to object-oriented solutions. If there is no OOP solution (and that would seem unlikely given apps written in SmallTalk, C++, Java, C# and all the other OOP-based languages) then one might find themselves forced into having to resort to a "hack". Take my word for it don't start with the "hack" or you will never stop applying hacks. People will stare at your code and giggle behind your back... What you are describing isn't a "module" you are describing a Singleton Class. If you want to read something perhaps about the Singleton Class would be a good start. Try it you may like it. Show quoteHide quote "Anil Gupte" <anil-l***@icinema.com> wrote in message news:OCFPtkBIHHA.3676@TK2MSFTNGP03.phx.gbl... > Thanx, that will get me started. Do you happen to know any place where I > can read more about when to use a Module and when to use a class? > > Thanx again, > -- > Anil Gupte > www.keeninc.net > www.icinema.com > > "Branco Medeiros" <branco.medei***@gmail.com> wrote in message > news:1166131605.256508.207250@n67g2000cwd.googlegroups.com... >> Anil Gupte wrote: >>> I am trying to set up a function that connects to the database that I >>> can >>> then use gloablly. I set up a class called L3Global in which I have a >>> function as follows: >> >>> Public Function SetDBConnect() >> <snip> >> >>> Now I want to use this is all my forms (MDI). I set up >>> Public L3G As New L3Global >>> >>> and then under the approporate button click I have: >>> Dim ConnL3Producer As New OleDbConnection >>> >>> ConnL3Producer = L3G.SetDBConnect >>> >>> The problem is, do I have to setup an instance of L3Global in each form? >>> That defeats the purpose, because each one opens a new connection. How >>> can >>> I use this connection object in all my forms but open it only once? >>> Ideally >>> I would like to move as much of the intialization (creating the >>> OLEDBAdapter >>> etc) to the global routine. >> <snip> >> >> I guess you can declare a Module, instead of a class: >> >> <aircode> >> Module L3Global >> Private mConnection As OleDBConnection >> >> Public Function ConnectDB() As OleDBConnection >> If mConnection Is Nothing Then >> Dim ConText As String = "Your connection string" >> mCOnnection = New OleDBConnectins(ConText) >> End If >> Return mConnection >> End Function >> End Module >> </aircode> >> >> And then, in your Forms you'd have: >> >> Dim ConnL3Producer _ >> As OleDbConnection = L3Global.ConnectDB() >> >> Improvise over that. >> >> Regards, >> >> Branco. >> > > Funny, I always thought a module was a Singleton Class!
-- Show quoteHide quoteDennis in Houston "Tom Leylan" wrote: > Anil: Yes you can read it right here :-) Never use a module! > > VB.Net is an object-oriented language and by definition that should lead to > object-oriented solutions. If there is no OOP solution (and that would seem > unlikely given apps written in SmallTalk, C++, Java, C# and all the other > OOP-based languages) then one might find themselves forced into having to > resort to a "hack". Take my word for it don't start with the "hack" or you > will never stop applying hacks. People will stare at your code and giggle > behind your back... > > What you are describing isn't a "module" you are describing a Singleton > Class. If you want to read something perhaps about the Singleton Class > would be a good start. > > Try it you may like it. > > "Anil Gupte" <anil-l***@icinema.com> wrote in message > news:OCFPtkBIHHA.3676@TK2MSFTNGP03.phx.gbl... > > Thanx, that will get me started. Do you happen to know any place where I > > can read more about when to use a Module and when to use a class? > > > > Thanx again, > > -- > > Anil Gupte > > www.keeninc.net > > www.icinema.com > > > > "Branco Medeiros" <branco.medei***@gmail.com> wrote in message > > news:1166131605.256508.207250@n67g2000cwd.googlegroups.com... > >> Anil Gupte wrote: > >>> I am trying to set up a function that connects to the database that I > >>> can > >>> then use gloablly. I set up a class called L3Global in which I have a > >>> function as follows: > >> > >>> Public Function SetDBConnect() > >> <snip> > >> > >>> Now I want to use this is all my forms (MDI). I set up > >>> Public L3G As New L3Global > >>> > >>> and then under the approporate button click I have: > >>> Dim ConnL3Producer As New OleDbConnection > >>> > >>> ConnL3Producer = L3G.SetDBConnect > >>> > >>> The problem is, do I have to setup an instance of L3Global in each form? > >>> That defeats the purpose, because each one opens a new connection. How > >>> can > >>> I use this connection object in all my forms but open it only once? > >>> Ideally > >>> I would like to move as much of the intialization (creating the > >>> OLEDBAdapter > >>> etc) to the global routine. > >> <snip> > >> > >> I guess you can declare a Module, instead of a class: > >> > >> <aircode> > >> Module L3Global > >> Private mConnection As OleDBConnection > >> > >> Public Function ConnectDB() As OleDBConnection > >> If mConnection Is Nothing Then > >> Dim ConText As String = "Your connection string" > >> mCOnnection = New OleDBConnectins(ConText) > >> End If > >> Return mConnection > >> End Function > >> End Module > >> </aircode> > >> > >> And then, in your Forms you'd have: > >> > >> Dim ConnL3Producer _ > >> As OleDbConnection = L3Global.ConnectDB() > >> > >> Improvise over that. > >> > >> Regards, > >> > >> Branco. > >> > > > > > > > Tom,
I hope to disappoint you, however it seems that C# programmers cannot stand the word "module". However a singleton C# class is as far as I know nothing more than a module, which residence at the stack. Beside the slight misbehaviour that a variable declared in a module can be called in VB.Net without its module name, is in my idea the module much nicer for declaring and using shared parts in a program. I would never write, "Never use a module", I agree with you when it becomes. "Try to avoid a module, static class, singleton, shared class or whatever you name them." Cor Show quoteHide quote "Tom Leylan" <tleylan@nospam.net> schreef in bericht news:%23GH2CULIHHA.3424@TK2MSFTNGP02.phx.gbl... > Anil: Yes you can read it right here :-) Never use a module! > > VB.Net is an object-oriented language and by definition that should lead > to object-oriented solutions. If there is no OOP solution (and that would > seem unlikely given apps written in SmallTalk, C++, Java, C# and all the > other OOP-based languages) then one might find themselves forced into > having to resort to a "hack". Take my word for it don't start with the > "hack" or you will never stop applying hacks. People will stare at your > code and giggle behind your back... > > What you are describing isn't a "module" you are describing a Singleton > Class. If you want to read something perhaps about the Singleton Class > would be a good start. > > Try it you may like it. > > "Anil Gupte" <anil-l***@icinema.com> wrote in message > news:OCFPtkBIHHA.3676@TK2MSFTNGP03.phx.gbl... >> Thanx, that will get me started. Do you happen to know any place where I >> can read more about when to use a Module and when to use a class? >> >> Thanx again, >> -- >> Anil Gupte >> www.keeninc.net >> www.icinema.com >> >> "Branco Medeiros" <branco.medei***@gmail.com> wrote in message >> news:1166131605.256508.207250@n67g2000cwd.googlegroups.com... >>> Anil Gupte wrote: >>>> I am trying to set up a function that connects to the database that I >>>> can >>>> then use gloablly. I set up a class called L3Global in which I have a >>>> function as follows: >>> >>>> Public Function SetDBConnect() >>> <snip> >>> >>>> Now I want to use this is all my forms (MDI). I set up >>>> Public L3G As New L3Global >>>> >>>> and then under the approporate button click I have: >>>> Dim ConnL3Producer As New OleDbConnection >>>> >>>> ConnL3Producer = L3G.SetDBConnect >>>> >>>> The problem is, do I have to setup an instance of L3Global in each >>>> form? >>>> That defeats the purpose, because each one opens a new connection. How >>>> can >>>> I use this connection object in all my forms but open it only once? >>>> Ideally >>>> I would like to move as much of the intialization (creating the >>>> OLEDBAdapter >>>> etc) to the global routine. >>> <snip> >>> >>> I guess you can declare a Module, instead of a class: >>> >>> <aircode> >>> Module L3Global >>> Private mConnection As OleDBConnection >>> >>> Public Function ConnectDB() As OleDBConnection >>> If mConnection Is Nothing Then >>> Dim ConText As String = "Your connection string" >>> mCOnnection = New OleDBConnectins(ConText) >>> End If >>> Return mConnection >>> End Function >>> End Module >>> </aircode> >>> >>> And then, in your Forms you'd have: >>> >>> Dim ConnL3Producer _ >>> As OleDbConnection = L3Global.ConnectDB() >>> >>> Improvise over that. >>> >>> Regards, >>> >>> Branco. >>> >> >> > > Hi Cor (and Dennis):
A quick search of newsgroup messages reveals that similar conversations have taken place before. One in particular involved Kevin Spencer explaining why the VB Module exists (backwards compatibility) and offering his opinion that it should have been removed. I agree with him. While it may constitute "a class with static properties and no constructor" I see no reason to provide a second syntax for creating such a thing. Why not a third or fourth syntax as well? I really don't want to rehash all the points because for every point made there will be a counterpoint and we simply duplicate countless other threads. I would hesitate to describe it as a Singleton class however. There is in fact a single object in a Singleton class and all properties do not need to be static. The instantiation of that object can be delayed until "first use". One can obtain a reference to the singleton object which can be passed as a parameter to other methods. If these things can be done with the VB module that's cool but again I ask why do we need two ways to obtain identical results? Furthermore we cannot create a singleton class using Module syntax subclassed from an arbitrary class right? So it is not only a "dupe" it is a limited use duplication. I believe it comes down to clarity of design. I can't explain it better but we don't need a language to implement every person's favorite way to do something. If anybody wants "module" functionality couldn't they simply declare a class in the way that the module does and get it? There it is, available to anybody who wants it, not part of the official language syntax, not misinterpreted as being a VB feature, etc. Cor, you're misinterpreting or simply guessing. It isn't that C# programmers can or cannot stand the word module. A C programmer doesn't think more clearly than a VB programmer, a dBASE programmer doesn't rank somewhere in a good programmer chart. There are good and bad (shall we call them neat and sloppy) programmers using every language. There is often a division between people who love having "&" and "+" available to concatenate strings and those who ask, why two operators? Some may find two ways "a brilliant design" while others will say it creates unnecessary ambiguity. I wouldn't say that C# developers find it odd and VB developers find it cool. The VB module doesn't add anything to the language (that I am aware of) and as such it should be removed from the language. Show quoteHide quote "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> wrote in message news:%233D%23WLhIHHA.2456@TK2MSFTNGP06.phx.gbl... > Tom, > > I hope to disappoint you, however it seems that C# programmers cannot > stand the word "module". > > However a singleton C# class is as far as I know nothing more than a > module, which residence at the stack. > > Beside the slight misbehaviour that a variable declared in a module can be > called in VB.Net without its module name, is in my idea the module much > nicer for declaring and using shared parts in a program. > > I would never write, "Never use a module", I agree with you when it > becomes. "Try to avoid a module, static class, singleton, shared class or > whatever you name them." > > Cor > > "Tom Leylan" <tleylan@nospam.net> schreef in bericht > news:%23GH2CULIHHA.3424@TK2MSFTNGP02.phx.gbl... >> Anil: Yes you can read it right here :-) Never use a module! >> >> VB.Net is an object-oriented language and by definition that should lead >> to object-oriented solutions. If there is no OOP solution (and that >> would seem unlikely given apps written in SmallTalk, C++, Java, C# and >> all the other OOP-based languages) then one might find themselves forced >> into having to resort to a "hack". Take my word for it don't start with >> the "hack" or you will never stop applying hacks. People will stare at >> your code and giggle behind your back... >> >> What you are describing isn't a "module" you are describing a Singleton >> Class. If you want to read something perhaps about the Singleton Class >> would be a good start. >> >> Try it you may like it. >> >> "Anil Gupte" <anil-l***@icinema.com> wrote in message >> news:OCFPtkBIHHA.3676@TK2MSFTNGP03.phx.gbl... >>> Thanx, that will get me started. Do you happen to know any place where >>> I can read more about when to use a Module and when to use a class? >>> >>> Thanx again, >>> -- >>> Anil Gupte >>> www.keeninc.net >>> www.icinema.com >>> >>> "Branco Medeiros" <branco.medei***@gmail.com> wrote in message >>> news:1166131605.256508.207250@n67g2000cwd.googlegroups.com... >>>> Anil Gupte wrote: >>>>> I am trying to set up a function that connects to the database that I >>>>> can >>>>> then use gloablly. I set up a class called L3Global in which I have a >>>>> function as follows: >>>> >>>>> Public Function SetDBConnect() >>>> <snip> >>>> >>>>> Now I want to use this is all my forms (MDI). I set up >>>>> Public L3G As New L3Global >>>>> >>>>> and then under the approporate button click I have: >>>>> Dim ConnL3Producer As New OleDbConnection >>>>> >>>>> ConnL3Producer = L3G.SetDBConnect >>>>> >>>>> The problem is, do I have to setup an instance of L3Global in each >>>>> form? >>>>> That defeats the purpose, because each one opens a new connection. >>>>> How can >>>>> I use this connection object in all my forms but open it only once? >>>>> Ideally >>>>> I would like to move as much of the intialization (creating the >>>>> OLEDBAdapter >>>>> etc) to the global routine. >>>> <snip> >>>> >>>> I guess you can declare a Module, instead of a class: >>>> >>>> <aircode> >>>> Module L3Global >>>> Private mConnection As OleDBConnection >>>> >>>> Public Function ConnectDB() As OleDBConnection >>>> If mConnection Is Nothing Then >>>> Dim ConText As String = "Your connection string" >>>> mCOnnection = New OleDBConnectins(ConText) >>>> End If >>>> Return mConnection >>>> End Function >>>> End Module >>>> </aircode> >>>> >>>> And then, in your Forms you'd have: >>>> >>>> Dim ConnL3Producer _ >>>> As OleDbConnection = L3Global.ConnectDB() >>>> >>>> Improvise over that. >>>> >>>> Regards, >>>> >>>> Branco. >>>> >>> >>> >> >> > > Tom,
A class in OOP has to be instanced, (you wrote it in my idea yourself) so that it can sit on the heap. You are true that I am guessing that a Singleton Class is doing the same as a so called not official existing Static Class in C# does, I could not yet find it where it residence, so I should not have written that. There are differences in with the VB Module and the Singleton, however as much as the behaviour between + and $ concationation in VB. I like however the name "Module". It makes it for me very clear, that a module is not a class, it is a part of the main object as it is fixed in the program. An instances object however sits on the managed heap and will be as as soon as that is possible removed. I find this name Module therefore nicer than any Shared/Static class, which is in fact no class in the OOP meaning. It is possible to write a Module in the same way as a class, and be than not forced to use the Shared keyword. In a very short discussion between Kevin Spencer and me about this (with a very small sample from me) he somewhere wrote a relative short while ago something in these newsgroups as. "You are right Cor, I did not know this behaviour from the Module". However, to search special messages on Google from either Kevin or me is not easy. Cor Show quoteHide quote "Tom Leylan" <tleylan@nospam.net> schreef in bericht news:eZiI8qhIHHA.2232@TK2MSFTNGP02.phx.gbl... > Hi Cor (and Dennis): > > A quick search of newsgroup messages reveals that similar conversations > have taken place before. One in particular involved Kevin Spencer > explaining why the VB Module exists (backwards compatibility) and offering > his opinion that it should have been removed. I agree with him. > > While it may constitute "a class with static properties and no > constructor" I see no reason to provide a second syntax for creating such > a thing. Why not a third or fourth syntax as well? I really don't want > to rehash all the points because for every point made there will be a > counterpoint and we simply duplicate countless other threads. > > I would hesitate to describe it as a Singleton class however. There is in > fact a single object in a Singleton class and all properties do not need > to be static. The instantiation of that object can be delayed until > "first use". One can obtain a reference to the singleton object which can > be passed as a parameter to other methods. If these things can be done > with the VB module that's cool but again I ask why do we need two ways to > obtain identical results? Furthermore we cannot create a singleton class > using Module syntax subclassed from an arbitrary class right? So it is > not only a "dupe" it is a limited use duplication. > > I believe it comes down to clarity of design. I can't explain it better > but we don't need a language to implement every person's favorite way to > do something. If anybody wants "module" functionality couldn't they > simply declare a class in the way that the module does and get it? There > it is, available to anybody who wants it, not part of the official > language syntax, not misinterpreted as being a VB feature, etc. > > Cor, you're misinterpreting or simply guessing. It isn't that C# > programmers can or cannot stand the word module. A C programmer doesn't > think more clearly than a VB programmer, a dBASE programmer doesn't rank > somewhere in a good programmer chart. There are good and bad (shall we > call them neat and sloppy) programmers using every language. There is > often a division between people who love having "&" and "+" available to > concatenate strings and those who ask, why two operators? Some may find > two ways "a brilliant design" while others will say it creates unnecessary > ambiguity. I wouldn't say that C# developers find it odd and VB > developers find it cool. > > The VB module doesn't add anything to the language (that I am aware of) > and as such it should be removed from the language. > > > "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> wrote in message > news:%233D%23WLhIHHA.2456@TK2MSFTNGP06.phx.gbl... >> Tom, >> >> I hope to disappoint you, however it seems that C# programmers cannot >> stand the word "module". >> >> However a singleton C# class is as far as I know nothing more than a >> module, which residence at the stack. >> >> Beside the slight misbehaviour that a variable declared in a module can >> be called in VB.Net without its module name, is in my idea the module >> much nicer for declaring and using shared parts in a program. >> >> I would never write, "Never use a module", I agree with you when it >> becomes. "Try to avoid a module, static class, singleton, shared class or >> whatever you name them." >> >> Cor >> >> "Tom Leylan" <tleylan@nospam.net> schreef in bericht >> news:%23GH2CULIHHA.3424@TK2MSFTNGP02.phx.gbl... >>> Anil: Yes you can read it right here :-) Never use a module! >>> >>> VB.Net is an object-oriented language and by definition that should lead >>> to object-oriented solutions. If there is no OOP solution (and that >>> would seem unlikely given apps written in SmallTalk, C++, Java, C# and >>> all the other OOP-based languages) then one might find themselves forced >>> into having to resort to a "hack". Take my word for it don't start with >>> the "hack" or you will never stop applying hacks. People will stare at >>> your code and giggle behind your back... >>> >>> What you are describing isn't a "module" you are describing a Singleton >>> Class. If you want to read something perhaps about the Singleton Class >>> would be a good start. >>> >>> Try it you may like it. >>> >>> "Anil Gupte" <anil-l***@icinema.com> wrote in message >>> news:OCFPtkBIHHA.3676@TK2MSFTNGP03.phx.gbl... >>>> Thanx, that will get me started. Do you happen to know any place where >>>> I can read more about when to use a Module and when to use a class? >>>> >>>> Thanx again, >>>> -- >>>> Anil Gupte >>>> www.keeninc.net >>>> www.icinema.com >>>> >>>> "Branco Medeiros" <branco.medei***@gmail.com> wrote in message >>>> news:1166131605.256508.207250@n67g2000cwd.googlegroups.com... >>>>> Anil Gupte wrote: >>>>>> I am trying to set up a function that connects to the database that I >>>>>> can >>>>>> then use gloablly. I set up a class called L3Global in which I have >>>>>> a >>>>>> function as follows: >>>>> >>>>>> Public Function SetDBConnect() >>>>> <snip> >>>>> >>>>>> Now I want to use this is all my forms (MDI). I set up >>>>>> Public L3G As New L3Global >>>>>> >>>>>> and then under the approporate button click I have: >>>>>> Dim ConnL3Producer As New OleDbConnection >>>>>> >>>>>> ConnL3Producer = L3G.SetDBConnect >>>>>> >>>>>> The problem is, do I have to setup an instance of L3Global in each >>>>>> form? >>>>>> That defeats the purpose, because each one opens a new connection. >>>>>> How can >>>>>> I use this connection object in all my forms but open it only once? >>>>>> Ideally >>>>>> I would like to move as much of the intialization (creating the >>>>>> OLEDBAdapter >>>>>> etc) to the global routine. >>>>> <snip> >>>>> >>>>> I guess you can declare a Module, instead of a class: >>>>> >>>>> <aircode> >>>>> Module L3Global >>>>> Private mConnection As OleDBConnection >>>>> >>>>> Public Function ConnectDB() As OleDBConnection >>>>> If mConnection Is Nothing Then >>>>> Dim ConText As String = "Your connection string" >>>>> mCOnnection = New OleDBConnectins(ConText) >>>>> End If >>>>> Return mConnection >>>>> End Function >>>>> End Module >>>>> </aircode> >>>>> >>>>> And then, in your Forms you'd have: >>>>> >>>>> Dim ConnL3Producer _ >>>>> As OleDbConnection = L3Global.ConnectDB() >>>>> >>>>> Improvise over that. >>>>> >>>>> Regards, >>>>> >>>>> Branco. >>>>> >>>> >>>> >>> >>> >> >> > > Tom,
My expection that the Singleton is not instanced but seats on the Main part is that it is in my eyes very inefficient to do it in another way if it has to be forever in a program. Cor Show quoteHide quote "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> schreef in bericht news:eMiSmcmIHHA.3952@TK2MSFTNGP02.phx.gbl... > Tom, > > A class in OOP has to be instanced, (you wrote it in my idea yourself) so > that it can sit on the heap. You are true that I am guessing that a > Singleton Class is doing the same as a so called not official existing > Static Class in C# does, I could not yet find it where it residence, so I > should not have written that. There are differences in with the VB Module > and the Singleton, however as much as the behaviour between + and $ > concationation in VB. > > I like however the name "Module". It makes it for me very clear, that a > module is not a class, it is a part of the main object as it is fixed in > the program. An instances object however sits on the managed heap and will > be as as soon as that is possible removed. I find this name Module > therefore nicer than any Shared/Static class, which is in fact no class in > the OOP meaning. > > It is possible to write a Module in the same way as a class, and be than > not forced to use the Shared keyword. In a very short discussion between > Kevin Spencer and me about this (with a very small sample from me) he > somewhere wrote a relative short while ago something in these newsgroups > as. "You are right Cor, I did not know this behaviour from the Module". > However, to search special messages on Google from either Kevin or me is > not easy. > > Cor > > > "Tom Leylan" <tleylan@nospam.net> schreef in bericht > news:eZiI8qhIHHA.2232@TK2MSFTNGP02.phx.gbl... >> Hi Cor (and Dennis): >> >> A quick search of newsgroup messages reveals that similar conversations >> have taken place before. One in particular involved Kevin Spencer >> explaining why the VB Module exists (backwards compatibility) and >> offering his opinion that it should have been removed. I agree with him. >> >> While it may constitute "a class with static properties and no >> constructor" I see no reason to provide a second syntax for creating such >> a thing. Why not a third or fourth syntax as well? I really don't want >> to rehash all the points because for every point made there will be a >> counterpoint and we simply duplicate countless other threads. >> >> I would hesitate to describe it as a Singleton class however. There is >> in fact a single object in a Singleton class and all properties do not >> need to be static. The instantiation of that object can be delayed until >> "first use". One can obtain a reference to the singleton object which >> can be passed as a parameter to other methods. If these things can be >> done with the VB module that's cool but again I ask why do we need two >> ways to obtain identical results? Furthermore we cannot create a >> singleton class using Module syntax subclassed from an arbitrary class >> right? So it is not only a "dupe" it is a limited use duplication. >> >> I believe it comes down to clarity of design. I can't explain it better >> but we don't need a language to implement every person's favorite way to >> do something. If anybody wants "module" functionality couldn't they >> simply declare a class in the way that the module does and get it? There >> it is, available to anybody who wants it, not part of the official >> language syntax, not misinterpreted as being a VB feature, etc. >> >> Cor, you're misinterpreting or simply guessing. It isn't that C# >> programmers can or cannot stand the word module. A C programmer doesn't >> think more clearly than a VB programmer, a dBASE programmer doesn't rank >> somewhere in a good programmer chart. There are good and bad (shall we >> call them neat and sloppy) programmers using every language. There is >> often a division between people who love having "&" and "+" available to >> concatenate strings and those who ask, why two operators? Some may find >> two ways "a brilliant design" while others will say it creates >> unnecessary ambiguity. I wouldn't say that C# developers find it odd and >> VB developers find it cool. >> >> The VB module doesn't add anything to the language (that I am aware of) >> and as such it should be removed from the language. >> >> >> "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> wrote in message >> news:%233D%23WLhIHHA.2456@TK2MSFTNGP06.phx.gbl... >>> Tom, >>> >>> I hope to disappoint you, however it seems that C# programmers cannot >>> stand the word "module". >>> >>> However a singleton C# class is as far as I know nothing more than a >>> module, which residence at the stack. >>> >>> Beside the slight misbehaviour that a variable declared in a module can >>> be called in VB.Net without its module name, is in my idea the module >>> much nicer for declaring and using shared parts in a program. >>> >>> I would never write, "Never use a module", I agree with you when it >>> becomes. "Try to avoid a module, static class, singleton, shared class >>> or whatever you name them." >>> >>> Cor >>> >>> "Tom Leylan" <tleylan@nospam.net> schreef in bericht >>> news:%23GH2CULIHHA.3424@TK2MSFTNGP02.phx.gbl... >>>> Anil: Yes you can read it right here :-) Never use a module! >>>> >>>> VB.Net is an object-oriented language and by definition that should >>>> lead to object-oriented solutions. If there is no OOP solution (and >>>> that would seem unlikely given apps written in SmallTalk, C++, Java, C# >>>> and all the other OOP-based languages) then one might find themselves >>>> forced into having to resort to a "hack". Take my word for it don't >>>> start with the "hack" or you will never stop applying hacks. People >>>> will stare at your code and giggle behind your back... >>>> >>>> What you are describing isn't a "module" you are describing a Singleton >>>> Class. If you want to read something perhaps about the Singleton Class >>>> would be a good start. >>>> >>>> Try it you may like it. >>>> >>>> "Anil Gupte" <anil-l***@icinema.com> wrote in message >>>> news:OCFPtkBIHHA.3676@TK2MSFTNGP03.phx.gbl... >>>>> Thanx, that will get me started. Do you happen to know any place >>>>> where I can read more about when to use a Module and when to use a >>>>> class? >>>>> >>>>> Thanx again, >>>>> -- >>>>> Anil Gupte >>>>> www.keeninc.net >>>>> www.icinema.com >>>>> >>>>> "Branco Medeiros" <branco.medei***@gmail.com> wrote in message >>>>> news:1166131605.256508.207250@n67g2000cwd.googlegroups.com... >>>>>> Anil Gupte wrote: >>>>>>> I am trying to set up a function that connects to the database that >>>>>>> I can >>>>>>> then use gloablly. I set up a class called L3Global in which I have >>>>>>> a >>>>>>> function as follows: >>>>>> >>>>>>> Public Function SetDBConnect() >>>>>> <snip> >>>>>> >>>>>>> Now I want to use this is all my forms (MDI). I set up >>>>>>> Public L3G As New L3Global >>>>>>> >>>>>>> and then under the approporate button click I have: >>>>>>> Dim ConnL3Producer As New OleDbConnection >>>>>>> >>>>>>> ConnL3Producer = L3G.SetDBConnect >>>>>>> >>>>>>> The problem is, do I have to setup an instance of L3Global in each >>>>>>> form? >>>>>>> That defeats the purpose, because each one opens a new connection. >>>>>>> How can >>>>>>> I use this connection object in all my forms but open it only once? >>>>>>> Ideally >>>>>>> I would like to move as much of the intialization (creating the >>>>>>> OLEDBAdapter >>>>>>> etc) to the global routine. >>>>>> <snip> >>>>>> >>>>>> I guess you can declare a Module, instead of a class: >>>>>> >>>>>> <aircode> >>>>>> Module L3Global >>>>>> Private mConnection As OleDBConnection >>>>>> >>>>>> Public Function ConnectDB() As OleDBConnection >>>>>> If mConnection Is Nothing Then >>>>>> Dim ConText As String = "Your connection string" >>>>>> mCOnnection = New OleDBConnectins(ConText) >>>>>> End If >>>>>> Return mConnection >>>>>> End Function >>>>>> End Module >>>>>> </aircode> >>>>>> >>>>>> And then, in your Forms you'd have: >>>>>> >>>>>> Dim ConnL3Producer _ >>>>>> As OleDbConnection = L3Global.ConnectDB() >>>>>> >>>>>> Improvise over that. >>>>>> >>>>>> Regards, >>>>>> >>>>>> Branco. >>>>>> >>>>> >>>>> >>>> >>>> >>> >>> >> >> > > Tom Leylan wrote (inline):
> Anil: Yes you can read it right here :-) Never use a module! I wouldn't go as far as to recommend to *never* use a module. There aretimes when the extra syntax needed to create a module-like class just gets in the way. VB gives you the tools and a Module is just one of them. Understand it and use it. > VB.Net is an object-oriented language and by definition that should lead to Yep, the C# 2.0 folks would do that, allright. They'd say "Look, they> object-oriented solutions. If there is no OOP solution (and that would seem > unlikely given apps written in SmallTalk, C++, Java, C# and all the other > OOP-based languages) then one might find themselves forced into having to > resort to a "hack". Take my word for it don't start with the "hack" or you > will never stop applying hacks. People will stare at your code and giggle > behind your back... call static classes a 'module'!". =))) BTW, C++ folks may also be intrigued by why are we using such an arcane construct, cause 99% of the C++ coders I know write OOP-only code... oops, sorry, I guess I got these stats reversed. > What you are describing isn't a "module" you are describing a Singleton No arguing about that... =)> Class. If you want to read something perhaps about the Singleton Class > would be a good start. One of the ways to provide singleton-like functionality is to hide the actual singleton inside a, uh, module, and provide only controlled access to it through the methods of the module. Of course, you may approach singletons however you like. Unfortunately, IMHO, the SomeClassWithPrivateConstructor.CreateInstance() approach to singletons, besides tasting much like Java, lacks the clarity of the good old "New Someclass()". Regards, Branco. Hi Branco:
"Branco Medeiros" <branco.medei***@gmail.com> wrote in message I'm not arguing mind you but perhaps you could illustrate one of those news:1166453209.535423.269790@j72g2000cwa.googlegroups.com... > > Tom Leylan wrote (inline): > >> Anil: Yes you can read it right here :-) Never use a module! > > I wouldn't go as far as to recommend to *never* use a module. There are > times when the extra syntax needed to create a module-like class just > gets in the way. VB gives you the tools and a Module is just one of > them. Understand it and use it. times. My point in most of these discussions (regardless of the language) is to ask why then haven't other languages adopted this really cool thing? More dramatically if dBASE has a CLEAR ALL command which removes all variables from memory (and it was a "good" feature rather than a horrid one) why wouldn't the developers using C, Pascal, VB and such be begging for it? > Yep, the C# 2.0 folks would do that, allright. They'd say "Look, they This is the part I don't understand. I have static classes in VB and I have > call static classes a 'module'!". =))) no modules so what am I missing? Why not eliminate the keyword CLASS from VB and just call them all MODULE? I think it depends upon one's goal and increasing the differences between languages shouldn't be a goal. If a keyword is available in C# and in VB I see no reason to change one of them in an effort to make things harder. I wouldn't add curly braces to VB but I can't see using new words to describe common concepts. All I'm saying is if a module is a static class what is the difficulty in calling them a static class? > One of the ways to provide singleton-like functionality is to hide the You can hide it anywhere you like but I haven't used a single module and I'm > actual singleton inside a, uh, module, and provide only controlled > access to it through the methods of the module. Of course, you may > approach singletons however you like. Unfortunately, IMHO, the > SomeClassWithPrivateConstructor.CreateInstance() approach to > singletons, besides tasting much like Java, lacks the clarity of the > good old "New Someclass()". not finding things harder to use or taking longer to write. I don't see the upside and I see lots of downside to modules. I also don't see anything wrong (from a language standpoint) with Java. I routinely steal good ideas from every language I've ever encountered. I also don't use every feature in a language just because it is available. That VB could reference a variable without previously declaring it was something it could do but I have yet to find an example that illustrated why it was needed or should be used. I understand that VB supports placing functions in modules, I'm suggesting (in the long run) it isn't wise to do so. Most people's mileage is likely to differ :-) Tom Leylan wrote:
<snip> > > There are I guess this actual thread illustrates such a case.> > times when the extra syntax needed to create a module-like class just > > gets in the way. > I'm not arguing mind you but perhaps you could illustrate one of those > times. > My point in most of these discussions (regardless of the language) This is not the point. It seems that every important -- some of them> is to ask why then haven't other languages adopted this really cool thing? > More dramatically if dBASE has a CLEAR ALL command which removes all > variables from memory (and it was a "good" feature rather than a horrid one) > why wouldn't the developers using C, Pascal, VB and such be begging for it? even cool -- models of computation was already done with by now; modern language developers are mostly adapting features and stealing sugar. But languages sometimes don't borrow from one-another even when something is "cool". Mostly there's a philosophy issue behind the scenes. Maybe the "stealing" exists, but it's so subtle you can't even see it's there. How many things Basic (and even VB) stole from Fortran? How much Java stole from VB? (look very close and you'll see a lot). As for "clear all", I kinda recall MSX-Basic (from Microsoft breed) had something like that to clear the garbage collector allocated space, back in, what, the 80s? C'mon... I admire people who can code in Perl, and I'm not one of them. Not that I lack the expertise, mind you, I really believe I can be an average-to-good programmer in most programming languages (something laughed here inside myself, but don't listen to it). I don't code in Perl because the language doesn't appeal to me. VB, on the other side, is cool in me, and I'm glad Modules have survived the transition to OOP without becoming a hack. I'd rather declare a Module -- something the VB programmer will immediatly recognize for what it is -- than to come up with solutions such as having a shared Singleton() method in a final class with a private constructor... Not that I'm saying I won't use that, only that I preffer not to. On the other side, a public ConnectDB() method inside a module will immediatly make it clear to me that it's the global scope speaking. > > Yep, the C# 2.0 folks would do that, allright. They'd say "Look, they You're talking about the C# folks, right? Why they didn't call a static> > call static classes a 'module'!". =))) > > This is the part I don't understand. I have static classes in VB and I have > no modules so what am I missing? Why not eliminate the keyword CLASS from > VB and just call them all MODULE? I think it depends upon one's goal and > increasing the differences between languages shouldn't be a goal. If a > keyword is available in C# and in VB I see no reason to change one of them > in an effort to make things harder. I wouldn't add curly braces to VB but I > can't see using new words to describe common concepts. All I'm saying is if > a module is a static class what is the difficulty in calling them a static > class? class simply a module, right? Because, AFAIK, the module "concept" existed in VB long before the C# folks noticed it. Nevertheless, a couple of most likely reasons to why "static classes" are called Module in VB: a) because the term "static" in VB has a very specific meaning, different from the ones it has in C#/C++/Java/C: in such languages, "static" inside a function declaration means the same as in VB: that the variable is, er, static (i.e. preserved between calls). Outside a function declaration, it designate elements shared by all instances of a class (quite a different meaning, I guess you'll aggree). In VB, by its turn, a method can be Static, which means that all its internal variables are static. If you want the C# meaning you must use the term "Shared". b) because the term "Module" already existed to represent the exact same thing as C#'s "static class". To be honest, I'm kinda proud of those keywords that represent concepts that VB pioneered -- or at least brought to the general knowledge -- and that were taken hold by other languages, sometimes having their names changed to cover the evidenc... er, I mean, to suit the language better, such as For Each, Event (for event-driven programming), Interface, Module, etc. This doesn't mean I even *like* those keywords VB invented to represent concepts already stablished in the programming field (MustInherit and NotInheritable to name a few). <snip> > You can hide it anywhere you like but I haven't used a single module and I'm Ahw, sure. I just don't sympathize with that guy Scott. Taking that,> not finding things harder to use or taking longer to write. I don't see the > upside and I see lots of downside to modules. I also don't see anything > wrong (from a language standpoint) with Java. Java is ok to me. My point was that there's already A-Way-To-Do-IT (tm) in VB, I'll use Java's way only if there's no VB way (or if the Java way is more close to my liking. I'm a bitch, I know). Notice that Java recently was given Properties, Enums and ForEach, and two of those were practically born with VB (well, ForEach was born with Pearl, and Properties were created by TurboPascal, to be exact, but I doubt they'd have any importance if it wasn't for VB... After all, VB's ForEach gave headaches to more than one C++ developer when it came to programming IDispatch interfaces. Now every language demands a foreach construct, but they should name it "VBForEach", to be honest. Nope, just kidding, strike that). <snip> > Most people's mileage is likely to differ :-) This, I fully aggree.Regards, Branco. responses inline:
"Branco Medeiros" <branco.medei***@gmail.com> wrote in message I just have to say then that I don't get it. If this thread illustrates an news:1166471796.055776.180170@n67g2000cwd.googlegroups.com... > Tom Leylan wrote: > <snip> >> > There are >> > times when the extra syntax needed to create a module-like class just >> > gets in the way. > >> I'm not arguing mind you but perhaps you could illustrate one of those >> times. > > I guess this actual thread illustrates such a case. example where the module is superior then how is every other OOP language without modules going to do this? And it would seem I couldn't solve the problem since I'm not going to use a module. Don't you see this thread doesn't illustrate a great example but rather just "an" example. Nothing that can't be solved as elegantly using class syntax which already exists. Show quoteHide quote >> My point in most of these discussions (regardless of the language) I'm going to guess that fundamentally everything in BASIC came from FORTRAN >> is to ask why then haven't other languages adopted this really cool >> thing? >> More dramatically if dBASE has a CLEAR ALL command which removes all >> variables from memory (and it was a "good" feature rather than a horrid >> one) >> why wouldn't the developers using C, Pascal, VB and such be begging for >> it? > > This is not the point. It seems that every important -- some of them > even cool -- models of computation was already done with by now; modern > language developers are mostly adapting features and stealing sugar. > But languages sometimes don't borrow from one-another even when > something is "cool". Mostly there's a philosophy issue behind the > scenes. Maybe the "stealing" exists, but it's so subtle you can't even > see it's there. How many things Basic (and even VB) stole from Fortran? > How much Java stole from VB? (look very close and you'll see a lot). As > for "clear all", I kinda recall MSX-Basic (from Microsoft breed) had > something like that to clear the garbage collector allocated space, > back in, what, the 80s? C'mon... via ALGOL. I'd also hazard a guess that virtually nothing from Java was borrowed from VB. VB wasn't an OOP language and only now rivals Java. You're mixing up whatever MSX-Basic did with what dBASE languages "do." And I don't mean in 1980 I mean last week. I sense a "defend VB" thing going on though, it's a language (an electronic toolset) not a religion. > I admire people who can code in Perl, and I'm not one of them. Not that That's great and I think we should leave it at that. I'm not a "VB > I lack the expertise, mind you, I really believe I can be an > average-to-good programmer in most programming languages (something > laughed here inside myself, but don't listen to it). I don't code in > Perl because the language doesn't appeal to me. VB, on the other side, > is cool in me, and I'm glad Modules have survived the transition to OOP > without becoming a hack. I'd rather declare a Module -- something the > VB programmer will immediatly recognize for what it is -- than to come > up with solutions such as having a shared Singleton() method in a final > class with a private constructor... Not that I'm saying I won't use > that, only that I preffer not to. On the other side, a public > ConnectDB() method inside a module will immediatly make it clear to me > that it's the global scope speaking. programmer" I never hope to be one, I have never aspired to be one. I'm a software developer. Personally I would rather use the ConnectDB() method of the SQLServer class opening the possibility of my using the ConnectDB() method of the OracleServer class without modifying a module. Again I realize to the extreme that VB programmers belong to a cult and to be fair so do "Java programmers", "SmallTalk programmers" and others who identify with a toolset. Maybe it's time to start a thread about the best O/S or the best CPU, it may have been a few days. Show quoteHide quote >> > Yep, the C# 2.0 folks would do that, allright. They'd say "Look, they Okay thanks... the thread has died.>> > call static classes a 'module'!". =))) >> >> This is the part I don't understand. I have static classes in VB and I >> have >> no modules so what am I missing? Why not eliminate the keyword CLASS >> from >> VB and just call them all MODULE? I think it depends upon one's goal and >> increasing the differences between languages shouldn't be a goal. If a >> keyword is available in C# and in VB I see no reason to change one of >> them >> in an effort to make things harder. I wouldn't add curly braces to VB >> but I >> can't see using new words to describe common concepts. All I'm saying is >> if >> a module is a static class what is the difficulty in calling them a >> static >> class? > > You're talking about the C# folks, right? Why they didn't call a static > class simply a module, right? Because, AFAIK, the module "concept" > existed in VB long before the C# folks noticed it. Tom Leylan wrote (inline):
> responses inline: <snip>Show quoteHide quote > >> > There are I never said that this thread illustrates the superiority of modules> >> > times when the extra syntax needed to create a module-like class just > >> > gets in the way. > > > >> I'm not arguing mind you but perhaps you could illustrate one of those > >> times. > > > > I guess this actual thread illustrates such a case. > > I just have to say then that I don't get it. If this thread illustrates an > example where the module is superior then how is every other OOP language > without modules going to do this? And it would seem I couldn't solve the > problem since I'm not going to use a module. Don't you see this thread > doesn't illustrate a great example but rather just "an" example. Nothing > that can't be solved as elegantly using class syntax which already exists. over classes. Only that it illustrates, to me, a situation where the syntax of a module-like class would get in the way, to the point of making me prefer to use a module instead of the class solution itself. <snip> > Okay thanks... the thread has died. Af! Ok, then.Regards, Branco. (gets out musing about language wars, urban religions, cold coffee and parsing engines) Tom,
About your text, I agree with everything you wrote, with one thing you don't probably agree with me. VB.Net 2003 is for me the best program development tool I have ever seen. :-) CorCor,
I routinely rave about how nice it is to develop in Visual Studio. It's a very productive tool and I'd find it hard to believe some people don't think so. The problem (as I see it) is usually another form of language wars. A Java developer may not want to say VS is nice because he can't use it for development. Not terribly unlike a VB 6 developer talking OOP down or an early VB.Net developer talking anonymous methods, generics and partial classes down when they don't have them. VB.Net just got anonymous methods, Clipper had them 15+ years ago. I use VB.Net 2005 :-) Show quoteHide quote "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> wrote in message news:uDaXpyyIHHA.4848@TK2MSFTNGP04.phx.gbl... > Tom, > > About your text, I agree with everything you wrote, with one thing you > don't probably agree with me. > > VB.Net 2003 is for me the best program development tool I have ever seen. > > :-) > > Cor Branco,
I absolutely do not agree the part that you write about "Static". There is a static keyword in VB, and that describes what it does (although logically not technical). The Shared keyword describes in my idea much better logical what it does than the Static keyword in C#. In my opinion in the word Static in C# just a piece of legacy. Therefore let us not change the facts because the people using C derived languages tells. To give an anology: Worldwide Coffee describes much better what we are drinking than as it is in the jargon from C people. Java is for me an island from Indonesia. Coffee is a drink from a bean that long ago was smuggled from Brazil by Dutch people to Java where they started to cultivate it. The rest of your text we agree about, but that you knew probably already. :-) Just my thought,Cor Show quoteHide quote "Branco Medeiros" <branco.medei***@gmail.com> schreef in bericht news:1166471796.055776.180170@n67g2000cwd.googlegroups.com... > Tom Leylan wrote: > <snip> >> > There are >> > times when the extra syntax needed to create a module-like class just >> > gets in the way. > >> I'm not arguing mind you but perhaps you could illustrate one of those >> times. > > I guess this actual thread illustrates such a case. > >> My point in most of these discussions (regardless of the language) >> is to ask why then haven't other languages adopted this really cool >> thing? >> More dramatically if dBASE has a CLEAR ALL command which removes all >> variables from memory (and it was a "good" feature rather than a horrid >> one) >> why wouldn't the developers using C, Pascal, VB and such be begging for >> it? > > This is not the point. It seems that every important -- some of them > even cool -- models of computation was already done with by now; modern > language developers are mostly adapting features and stealing sugar. > But languages sometimes don't borrow from one-another even when > something is "cool". Mostly there's a philosophy issue behind the > scenes. Maybe the "stealing" exists, but it's so subtle you can't even > see it's there. How many things Basic (and even VB) stole from Fortran? > How much Java stole from VB? (look very close and you'll see a lot). As > for "clear all", I kinda recall MSX-Basic (from Microsoft breed) had > something like that to clear the garbage collector allocated space, > back in, what, the 80s? C'mon... > > I admire people who can code in Perl, and I'm not one of them. Not that > I lack the expertise, mind you, I really believe I can be an > average-to-good programmer in most programming languages (something > laughed here inside myself, but don't listen to it). I don't code in > Perl because the language doesn't appeal to me. VB, on the other side, > is cool in me, and I'm glad Modules have survived the transition to OOP > without becoming a hack. I'd rather declare a Module -- something the > VB programmer will immediatly recognize for what it is -- than to come > up with solutions such as having a shared Singleton() method in a final > class with a private constructor... Not that I'm saying I won't use > that, only that I preffer not to. On the other side, a public > ConnectDB() method inside a module will immediatly make it clear to me > that it's the global scope speaking. > > >> > Yep, the C# 2.0 folks would do that, allright. They'd say "Look, they >> > call static classes a 'module'!". =))) >> >> This is the part I don't understand. I have static classes in VB and I >> have >> no modules so what am I missing? Why not eliminate the keyword CLASS >> from >> VB and just call them all MODULE? I think it depends upon one's goal and >> increasing the differences between languages shouldn't be a goal. If a >> keyword is available in C# and in VB I see no reason to change one of >> them >> in an effort to make things harder. I wouldn't add curly braces to VB >> but I >> can't see using new words to describe common concepts. All I'm saying is >> if >> a module is a static class what is the difficulty in calling them a >> static >> class? > > You're talking about the C# folks, right? Why they didn't call a static > class simply a module, right? Because, AFAIK, the module "concept" > existed in VB long before the C# folks noticed it. Nevertheless, a > couple of most likely reasons to why "static classes" are called Module > in VB: a) because the term "static" in VB has a very specific meaning, > different from the ones it has in C#/C++/Java/C: in such languages, > "static" inside a function declaration means the same as in VB: that > the variable is, er, static (i.e. preserved between calls). Outside a > function declaration, it designate elements shared by all instances of > a class (quite a different meaning, I guess you'll aggree). In VB, by > its turn, a method can be Static, which means that all its internal > variables are static. If you want the C# meaning you must use the term > "Shared". b) because the term "Module" already existed to represent the > exact same thing as C#'s "static class". > > To be honest, I'm kinda proud of those keywords that represent > concepts that VB pioneered -- or at least brought to the general > knowledge -- and that were taken hold by other languages, sometimes > having their names changed to cover the evidenc... er, I mean, to suit > the language better, such as For Each, Event (for event-driven > programming), Interface, Module, etc. > > This doesn't mean I even *like* those keywords VB invented to represent > concepts already stablished in the programming field (MustInherit and > NotInheritable to name a few). > > <snip> >> You can hide it anywhere you like but I haven't used a single module and >> I'm >> not finding things harder to use or taking longer to write. I don't see >> the >> upside and I see lots of downside to modules. I also don't see anything >> wrong (from a language standpoint) with Java. > > Ahw, sure. I just don't sympathize with that guy Scott. Taking that, > Java is ok to me. My point was that there's already A-Way-To-Do-IT (tm) > in VB, I'll use Java's way only if there's no VB way (or if the Java > way is more close to my liking. I'm a bitch, I know). > > Notice that Java recently was given Properties, Enums and ForEach, and > two of those were practically born with VB (well, ForEach was born with > Pearl, and Properties were created by TurboPascal, to be exact, but I > doubt they'd have any importance if it wasn't for VB... After all, VB's > ForEach gave headaches to more than one C++ developer when it came to > programming IDispatch interfaces. Now every language demands a foreach > construct, but they should name it "VBForEach", to be honest. Nope, > just kidding, strike that). > > <snip> >> Most people's mileage is likely to differ :-) > > This, I fully aggree. > > Regards, > > Branco. > Cor Ligthert [MVP] wrote:
> I absolutely do not agree the part that you write about "Static". There is a <snip>> static keyword in VB, and that describes what it does (although logically > not technical). Maybe I didn't make it very clear. I was not suggesting another use for the word "Static". I was actually pointing out that the usual meaning of the "static" keyword as found in languages such as C# and family is represented by the "Shared" keyword in VB. Regards, Brannco. 
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