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Best Practices - Coding Convention QuestionI'm still rather new at vb.net and would like to know the proper way to access private varibables in a class. Do I access the variable directly or do I use the public property? public class MyClass private _variableName as integer public property VariableName as integer get return _variableName end get set(byVal Value as integer) _variableName = value end set end property public sub DoSomething () ' do I use _variableName or ' do I use VariableName" end sub end class Thanks Ren wrote:
Show quoteHide quote > Hi All, Not sure of best practice on this, but from a practice level, if you use > > I'm still rather new at vb.net and would like to know the proper way to access > private varibables in a class. Do I access the variable directly or do I use > the public property? > > public class MyClass > private _variableName as integer > > public property VariableName as integer > get > return _variableName > end get > set(byVal Value as integer) > _variableName = value > end set > end property > > public sub DoSomething () > ' do I use _variableName or > ' do I use VariableName" > end sub > > end class > > Thanks the property it allows you to make changes during the get/set in the future w/o having to recode rest of the class. Chris Ren,
I use for the private variable mVariableName For the rest as you wrote with _variableName a notation that I hate. By the way there is never a Best Practice. Luckily this is always a part of discussion. Typical for the VBNet developper is that he/she is human and can change when it is needed and take the best Practice for that situation. Cor Show quoteHide quote "Ren" <nospam@nospam.org> schreef in bericht news:pfv222lb9h1jbljbmkof2hpi99m7t79fae@4ax.com... > Hi All, > > I'm still rather new at vb.net and would like to know the proper way to > access > private varibables in a class. Do I access the variable directly or do I > use > the public property? > > public class MyClass > private _variableName as integer > > public property VariableName as integer > get > return _variableName > end get > set(byVal Value as integer) > _variableName = value > end set > end property > > public sub DoSomething () > ' do I use _variableName or > ' do I use VariableName" > end sub > > end class > > Thanks Cor ,
> I use for the private variable funny the parctical guidelines book states that m_VariableName should be > mVariableName > > For the rest as you wrote with _variableName a notation that I hate. > used :-) > By the way there is never a Best Practice. Luckily this is always a part Have you ever heard of programming by MSF ?? MSF holds a colection of > of discussion. > > Typical for the VBNet developper is that he/she is human and can change > when it is needed and take the best Practice for that situation. practical guidelines and best practices wich includes naming conventions So these rules do exist ............. however do we want to implement them as strict as they are,, that is more the question If we would code by these rules our programs would be more readable and understandable , however practice learns that most coders prefer there own conventions ( you still see hungarion notation in .net code for stance ) or even worse program without anny conventions at all ( 90 % of the code i saw in my daily work was like this, and i have seen code from all over the world by all sorts of programmers ) ... So the guidelines do exist MS has verry nice documentation regarding this , however we , as programming comunity do not enforce them or expect them to be the standard ... that is the problem in my opinion . see for more info about MSF : http://www.microsoft.com/technet/itsolutions/msf/default.mspx personal recomendation regarding this : Practical Guidelines and best practices for Microsoft Visual Basic and visual C# Developers http://www.amazon.com/gp/product/0735621721/sr=8-1/qid=1143064376/ref=pd_bbs_1/102-6548994-9968922?%5Fencoding=UTF8 Having said this i will start packing my suitcase as my plain leaves tomorrow to the canary islands :-) i will have a 2 week holliday before i start my new job regards Michel Posseth [MCP] Show quoteHide quote "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> schreef in bericht news:eKd6wddTGHA.4600@TK2MSFTNGP11.phx.gbl... > Ren, > > I use for the private variable > mVariableName > > For the rest as you wrote with _variableName a notation that I hate. > > By the way there is never a Best Practice. Luckily this is always a part > of discussion. > > Typical for the VBNet developper is that he/she is human and can change > when it is needed and take the best Practice for that situation. > > Cor > > "Ren" <nospam@nospam.org> schreef in bericht > news:pfv222lb9h1jbljbmkof2hpi99m7t79fae@4ax.com... >> Hi All, >> >> I'm still rather new at vb.net and would like to know the proper way to >> access >> private varibables in a class. Do I access the variable directly or do I >> use >> the public property? >> >> public class MyClass >> private _variableName as integer >> >> public property VariableName as integer >> get >> return _variableName >> end get >> set(byVal Value as integer) >> _variableName = value >> end set >> end property >> >> public sub DoSomething () >> ' do I use _variableName or >> ' do I use VariableName" >> end sub >> >> end class >> >> Thanks > > Michel,
Did you ever look at modern Visual Basic samples on MSDN (not from C++ -> C# converted ones). Microsoft has showed much of those patterns, it seems for me that it depends who made it what it look like. Cor Show quoteHide quote "Michel Posseth [MCP]" <M***@posseth.com> schreef in bericht news:exKQgsfTGHA.1688@TK2MSFTNGP11.phx.gbl... > Cor , > >> I use for the private variable >> mVariableName >> >> For the rest as you wrote with _variableName a notation that I hate. >> > > funny the parctical guidelines book states that m_VariableName should be > used :-) > >> By the way there is never a Best Practice. Luckily this is always a part >> of discussion. >> >> Typical for the VBNet developper is that he/she is human and can change >> when it is needed and take the best Practice for that situation. > > Have you ever heard of programming by MSF ?? MSF holds a colection of > practical guidelines and best practices wich includes naming conventions > So these rules do exist ............. however do we want to implement them > as strict as they are,, that is more the question > > If we would code by these rules our programs would be more readable and > understandable , however practice learns that most coders prefer there own > conventions ( you still see hungarion notation in .net code for > ance ) or even worse program without anny conventions at all ( 90 % of > the code i saw in my daily work was like this, and i have seen code from > all over the world by all sorts of programmers ) ... > > So the guidelines do exist MS has verry nice documentation regarding this > , however we , as programming comunity do not enforce them or expect them > to be the standard ... that is the problem in my opinion . > > see for more info about MSF : > > http://www.microsoft.com/technet/itsolutions/msf/default.mspx > > personal recomendation regarding this : > > Practical Guidelines and best practices for Microsoft Visual Basic and > visual C# Developers > > http://www.amazon.com/gp/product/0735621721/sr=8-1/qid=1143064376/ref=pd_bbs_1/102-6548994-9968922?%5Fencoding=UTF8 > > > > Having said this i will start packing my suitcase as my plain leaves > tomorrow to the canary islands :-) > i will have a 2 week holliday before i start my new job > > regards > > Michel Posseth [MCP] > > > > "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> schreef in bericht > news:eKd6wddTGHA.4600@TK2MSFTNGP11.phx.gbl... >> Ren, >> >> I use for the private variable >> mVariableName >> >> For the rest as you wrote with _variableName a notation that I hate. >> >> By the way there is never a Best Practice. Luckily this is always a part >> of discussion. >> >> Typical for the VBNet developper is that he/she is human and can change >> when it is needed and take the best Practice for that situation. >> >> Cor >> >> "Ren" <nospam@nospam.org> schreef in bericht >> news:pfv222lb9h1jbljbmkof2hpi99m7t79fae@4ax.com... >>> Hi All, >>> >>> I'm still rather new at vb.net and would like to know the proper way to >>> access >>> private varibables in a class. Do I access the variable directly or do >>> I use >>> the public property? >>> >>> public class MyClass >>> private _variableName as integer >>> >>> public property VariableName as integer >>> get >>> return _variableName >>> end get >>> set(byVal Value as integer) >>> _variableName = value >>> end set >>> end property >>> >>> public sub DoSomething () >>> ' do I use _variableName or >>> ' do I use VariableName" >>> end sub >>> >>> end class >>> >>> Thanks >> >> > > "Ren" <nospam@nospam.org> schrieb: I consider accessing it through the property's 'Get'/'Set' accessor even > I'm still rather new at vb.net and would like to know the proper way to > access > private varibables in a class. Do I access the variable directly or do I > use > the public property? inside the class whereever possible good practice, because it will prevent assignment of invalid values to the property. Execution overhead is minimal because the JIT compiler can inline property access. -- M S Herfried K. Wagner M V P <URL:http://dotnet.mvps.org/> V B <URL:http://classicvb.org/petition/> I agree with Cor and Herfried. There is no reason to treat the property
differently within its class. It can only be cause of errors. If you feel you need it, it probably means you are doing something you should not, or you are doing it the wrong way. On the practical side the greatest advantage is that you just write "me." and you have all the properties there readily available (intellisense). It's a lot more convenient... -tom Something not addressed in the other posts...
If you always reference the private variable by its property-name and you need to search for where the property is referenced you only have to search for one thing -- the property. Otherwise, within the class wherein it's defined, you have to search for both the property-name and the variable-name. -- Lee Silver Information Concepts Inc. Ren wrote:
<snip> > I'm still rather new at vb.net and would like to know the proper way to access <snip>> private varibables in a class. Do I access the variable directly or do I use > the public property? > > public class MyClass > private _variableName as integer > > public property VariableName as integer > end property Properties were created to protect, and even hide, the internal> > public sub DoSomething () > ' do I use _variableName or > ' do I use VariableName" > end sub > > end class structure of the object from the outside world. Ideally, only the object itself should know about it's internal fields and how they relate to the exposed properties. Besides, properties allow for side-effects to happen when a given field is accessed. Therefore, a property actually encapsulates a behavior. Now, it's a very common practice to expose internal fields -- that were suposed to be public -- through properties, even though these properties are only getters/setters (I'm talking about just those properties that are both a getter and a setter for a given field). The reasoning is: a) you must not expose your internal fields and b) properties protect you by keeping your interface intact should the internal workings of the object change. But It turns out that I see more frequent changes to an in-progress object interface than to the internals of the object, usually because of unantecipated needs of the "external world" (from the object's perspective), even though the internal structure of the object remains more or less intact. Considering this, and as a left over from the time when compilers wouldn't be smart enough to inline the access to properties, my personal practice goes against (although not religiously) accessing internal fields via getter/setter properties. I mean, the object is in a priviledged position to see these fields, so it should also exercise direct access to them. Therefore, internally I'd use mVariableName, instead of the related properties. Regards, Branco.
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"Branco Medeiros" <branco.medei***@gmail.com> schrieb: Consider this sample:> Besides, properties allow for side-effects to happen when a given field > is accessed. Therefore, a property actually encapsulates a behavior. > > Now, it's a very common practice to expose internal fields -- that were > suposed to be public -- through properties, even though these > properties are only getters/setters (I'm talking about just those > properties that are both a getter and a setter for a given field). The > reasoning is: a) you must not expose your internal fields and b) > properties protect you by keeping your interface intact should the > internal workings of the object change. > > But It turns out that I see more frequent changes to an in-progress > object interface than to the internals of the object, usually because > of unantecipated needs of the "external world" (from the object's > perspective), even though the internal structure of the object remains > more or less intact. > > Considering this, and as a left over from the time when compilers > wouldn't be smart enough to inline the access to properties, my > personal practice goes against (although not religiously) accessing > internal fields via getter/setter properties. > > I mean, the object is in a priviledged position to see these fields, so > it should also exercise direct access to them. \\\ Private m_Bla As Integer Public Property Bla() As Integer Get Return m_Bla End Get Set(...) If Value < 0 OrElse Value > 10 Then Throw New ArgumentException(...) Else m_Bla = Value End If End Set End Property /// When assigning the value to 'm_Bla' directly you are bypassing validation and it's possible that the property value returned by 'Get' is an invalid value due to bugs in the code which cause an invalid value to be assigned to the private backing field. I strongly believe that it's better to have only a single code path to access 'm_Bla' than multiple paths. -- M S Herfried K. Wagner M V P <URL:http://dotnet.mvps.org/> V B <URL:http://classicvb.org/petition/> Hi Ren,
It depends on the case. In your example there is no difference, but there are cases where the Get/Set accessors execute additional code (validation, caching, etc) and in those cases you need to consider if you want that additional code to be executed or not. -- Show quoteHide quoteBest regards, Carlos J. Quintero MZ-Tools: Productivity add-ins for Visual Studio You can code, design and document much faster: http://www.mztools.com "Ren" <nospam@nospam.org> escribió en el mensaje news:pfv222lb9h1jbljbmkof2hpi99m7t79fae@4ax.com... > Hi All, > > I'm still rather new at vb.net and would like to know the proper way to > access > private varibables in a class. Do I access the variable directly or do I > use > the public property? > > public class MyClass > private _variableName as integer > > public property VariableName as integer > get > return _variableName > end get > set(byVal Value as integer) > _variableName = value > end set > end property > > public sub DoSomething () > ' do I use _variableName or > ' do I use VariableName" > end sub > > end class > > Thanks 
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