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late bindingHi,
I am working with the streams objects (filestream,streamwriter,streamreader) May I do or is it good programming to make a sub like : public sub Closestreams(ByRef ob as object) if not (ob is nothing) then ob.close ob = nothing end if end sub thanks for any response Andreas,
Is a simple close not more effective. The ob = nothing has no sense at all. Cor Show quoteHide quote "andreas" <andr***@pandora.be> schreef in bericht news:DZ8Tf.324646$4A1.10358835@phobos.telenet-ops.be... > Hi, > I am working with the streams objects > (filestream,streamwriter,streamreader) > May I do or is it good programming to make a sub like : > > public sub Closestreams(ByRef ob as object) > if not (ob is nothing) then > ob.close > ob = nothing > end if > end sub > > thanks for any response > > Well in my opinion this depends on the usage in his code of the object
example: sub DoSomeStuff () Dim objVar as new foo 'use the object ..... No need to explicitly set the var to Nothing End Sub '-----in this situation it makes sense to use Nothing sub DoSomeStuff () Dim objVar as new foo for i as integer = 1 to 1000 if i <= 50 then objvar.PerformsomeAction if i=50 then objVar = Nothing else 'do something else except using ObjVar end if next End Sub regards Michel Posseth [MCP] Show quoteHide quote "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> schreef in bericht news:OiFh2dzSGHA.4752@TK2MSFTNGP10.phx.gbl... > Andreas, > > Is a simple close not more effective. The ob = nothing has no sense at > all. > > Cor > > "andreas" <andr***@pandora.be> schreef in bericht > news:DZ8Tf.324646$4A1.10358835@phobos.telenet-ops.be... >> Hi, >> I am working with the streams objects >> (filestream,streamwriter,streamreader) >> May I do or is it good programming to make a sub like : >> >> public sub Closestreams(ByRef ob as object) >> if not (ob is nothing) then >> ob.close >> ob = nothing >> end if >> end sub >> >> thanks for any response >> >> > > Michel,,
If it was this code (and I don't believe somebody uses this with a stream object Private a as streamwriter Private sub b a = new streamwriter etc End Sub than it could have sense, however in my opinion is this not so clever code Normally and in your example does the sub goes out of scope and will be released by the GC. In your sample if there is set a reference from an other object to this object (and therefore will not be released to whatever nothing you set it), than setting to nothing does not add much, it goes out of scope if it has or has and not a reference. Just my thought, Cor Show quoteHide quote "Michel Posseth [MCP]" <M***@posseth.com> schreef in bericht news:OnAieP0SGHA.5116@TK2MSFTNGP14.phx.gbl... > Well in my opinion this depends on the usage in his code of the object > > example: > > sub DoSomeStuff () > Dim objVar as new foo > > 'use the object > .... > No need to explicitly set the var to Nothing > > End Sub > > '-----in this situation it makes sense to use Nothing > > sub DoSomeStuff () > Dim objVar as new foo > for i as integer = 1 to 1000 > if i <= 50 then > objvar.PerformsomeAction > if i=50 then objVar = Nothing > else > 'do something else except using ObjVar > end if > next > > End Sub > > > regards > > Michel Posseth [MCP] > > > > > > > > > "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> schreef in bericht > news:OiFh2dzSGHA.4752@TK2MSFTNGP10.phx.gbl... >> Andreas, >> >> Is a simple close not more effective. The ob = nothing has no sense at >> all. >> >> Cor >> >> "andreas" <andr***@pandora.be> schreef in bericht >> news:DZ8Tf.324646$4A1.10358835@phobos.telenet-ops.be... >>> Hi, >>> I am working with the streams objects >>> (filestream,streamwriter,streamreader) >>> May I do or is it good programming to make a sub like : >>> >>> public sub Closestreams(ByRef ob as object) >>> if not (ob is nothing) then >>> ob.close >>> ob = nothing >>> end if >>> end sub >>> >>> thanks for any response >>> >>> >> >> > > I agre with most of it ,,, but i guess you did not look carefully to example
2 ( where it is valid to use Nothing ) as you see we are in a loop with a codition set for usage of the object ,,, setting it to nothing after finished with it , makes it possible to collect the object before the method / loop has finished . As we never know when the GC kicks in it might also not do this i am aware of that however on a resource hungry system it might make a difference regards Michel Posseth [MCP] Show quoteHide quote "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> schreef in bericht news:e6WeAc0SGHA.4300@TK2MSFTNGP14.phx.gbl... > Michel,, > > If it was this code (and I don't believe somebody uses this with a stream > object > > Private a as streamwriter > Private sub b > a = new streamwriter > etc > End Sub > > than it could have sense, however in my opinion is this not so clever code > > Normally and in your example does the sub goes out of scope and will be > released by the GC. > > In your sample if there is set a reference from an other object to this > object (and therefore will not be released to whatever nothing you set > it), than setting to nothing does not add much, it goes out of scope if it > has or has and not a reference. > > Just my thought, > > Cor > > > "Michel Posseth [MCP]" <M***@posseth.com> schreef in bericht > news:OnAieP0SGHA.5116@TK2MSFTNGP14.phx.gbl... >> Well in my opinion this depends on the usage in his code of the object >> >> example: >> >> sub DoSomeStuff () >> Dim objVar as new foo >> >> 'use the object >> .... >> No need to explicitly set the var to Nothing >> >> End Sub >> >> '-----in this situation it makes sense to use Nothing >> >> sub DoSomeStuff () >> Dim objVar as new foo >> for i as integer = 1 to 1000 >> if i <= 50 then >> objvar.PerformsomeAction >> if i=50 then objVar = Nothing >> else >> 'do something else except using ObjVar >> end if >> next >> >> End Sub >> >> >> regards >> >> Michel Posseth [MCP] >> >> >> >> >> >> >> >> >> "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> schreef in bericht >> news:OiFh2dzSGHA.4752@TK2MSFTNGP10.phx.gbl... >>> Andreas, >>> >>> Is a simple close not more effective. The ob = nothing has no sense at >>> all. >>> >>> Cor >>> >>> "andreas" <andr***@pandora.be> schreef in bericht >>> news:DZ8Tf.324646$4A1.10358835@phobos.telenet-ops.be... >>>> Hi, >>>> I am working with the streams objects >>>> (filestream,streamwriter,streamreader) >>>> May I do or is it good programming to make a sub like : >>>> >>>> public sub Closestreams(ByRef ob as object) >>>> if not (ob is nothing) then >>>> ob.close >>>> ob = nothing >>>> end if >>>> end sub >>>> >>>> thanks for any response >>>> >>>> >>> >>> >> >> > > "andreas" <andr***@pandora.be> schrieb: (1) I am curious why you are passing 'ob' in as 'ByRef'. I suggest to> I am working with the streams objects > (filestream,streamwriter,streamreader) > May I do or is it good programming to make a sub like : > > public sub Closestreams(ByRef ob as object) > if not (ob is nothing) then > ob.close > ob = nothing > end if > end sub change 'ByRef' to 'ByVal'. (2) Why are you typing 'ob' as 'Object' and not as 'Stream' or similar? (3) Setting the variable to nothing doesn't make much sense here... -- M S Herfried K. Wagner M V P <URL:http://dotnet.mvps.org/> V B <URL:http://classicvb.org/petition/> I write the whole thing (with try and so on)
dim fs as new filestream(.......) dim sw as new streamwriter(fs) ... some code with sw dim ffss as new filestream(...) dim ssww as new streamreader(ffss) ....some code with ssww and now I want to close savely the whole thing closestreams(sw) closestreams(fs) closestreams(ssww) closestreams(ffss) and now I repeat my question about the sub closestreams Show quoteHide quote "Herfried K. Wagner [MVP]" <hirf-spam-me-here@gmx.at> schreef in bericht news:#iQrkH1SGHA.4492@TK2MSFTNGP09.phx.gbl... > "andreas" <andr***@pandora.be> schrieb: > > I am working with the streams objects > > (filestream,streamwriter,streamreader) > > May I do or is it good programming to make a sub like : > > > > public sub Closestreams(ByRef ob as object) > > if not (ob is nothing) then > > ob.close > > ob = nothing > > end if > > end sub > > (1) I am curious why you are passing 'ob' in as 'ByRef'. I suggest to > change 'ByRef' to 'ByVal'. > > (2) Why are you typing 'ob' as 'Object' and not as 'Stream' or similar? > > (3) Setting the variable to nothing doesn't make much sense here... > > -- > M S Herfried K. Wagner > M V P <URL:http://dotnet.mvps.org/> > V B <URL:http://classicvb.org/petition/> > Andreas,
What is in your opinion the advantage? I do not see any, I see only disadvantages. Cor Show quoteHide quote "andreas" <andr***@pandora.be> schreef in bericht news:ZEdTf.325175$Bu.10140738@phobos.telenet-ops.be... >I write the whole thing (with try and so on) > > dim fs as new filestream(.......) > dim sw as new streamwriter(fs) > .. some code with sw > dim ffss as new filestream(...) > dim ssww as new streamreader(ffss) > ...some code with ssww > > and now I want to close savely the whole thing > closestreams(sw) > closestreams(fs) > closestreams(ssww) > closestreams(ffss) > > and now I repeat my question about the sub closestreams > > > "Herfried K. Wagner [MVP]" <hirf-spam-me-here@gmx.at> schreef in bericht > news:#iQrkH1SGHA.4492@TK2MSFTNGP09.phx.gbl... >> "andreas" <andr***@pandora.be> schrieb: >> > I am working with the streams objects >> > (filestream,streamwriter,streamreader) >> > May I do or is it good programming to make a sub like : >> > >> > public sub Closestreams(ByRef ob as object) >> > if not (ob is nothing) then >> > ob.close >> > ob = nothing >> > end if >> > end sub >> >> (1) I am curious why you are passing 'ob' in as 'ByRef'. I suggest to >> change 'ByRef' to 'ByVal'. >> >> (2) Why are you typing 'ob' as 'Object' and not as 'Stream' or similar? >> >> (3) Setting the variable to nothing doesn't make much sense here... >> >> -- >> M S Herfried K. Wagner >> M V P <URL:http://dotnet.mvps.org/> >> V B <URL:http://classicvb.org/petition/> >> > > As Herfried says, it's pointless to set ob to Nothing - ob is just a
parameter that goes out of scope immediately after you are setting it to Nothing, so that's unnecessary. Excessive setting objects to Nothing is a holdover from classic VB (and even there it's not required as much as people think). Also, setting it Nothing in that method does not remove the reference in the calling method - but even there it's not practical unless your calling method is so long that you're worried about encouraging garbage collection as soon as possible (even then, "Using" is a more direct approach if that's your concern). So, all you're left with in your function is: if not (ob is nothing) then ob.close I think just using the Close methods on the objects directly from your calling method is cleaner. -- Show quoteHide quoteDavid Anton www.tangiblesoftwaresolutions.com Instant C#: VB to C# converter Instant VB: C# to VB converter Instant C++: C# to C++ converter & VB to C++ converter Instant J#: VB to J# converter "andreas" wrote: > Hi, > I am working with the streams objects (filestream,streamwriter,streamreader) > May I do or is it good programming to make a sub like : > > public sub Closestreams(ByRef ob as object) > if not (ob is nothing) then > ob.close > ob = nothing > end if > end sub > > thanks for any response > > > Well ......
It also doesn`t hurt , to use Nothing , and in a lot of MS examples i see Nothing used even better i found some articles that state that in some situations it might even benefit the GC to use Nothing . Can you clean to good in your home ??? and indeed as a VB6 progger i learned how to clean up my mess .... :-) in the example i showed in a above post for instance it is in my opinion perfectly valid to use Nothing , as it might help in the release of the object before the method has finished regards Michel Posseth [MCP] Show quoteHide quote "David Anton" <DavidAn***@discussions.microsoft.com> schreef in bericht news:DB6AD6BB-706A-438D-BD63-2831FFF9A043@microsoft.com... > As Herfried says, it's pointless to set ob to Nothing - ob is just a > parameter that goes out of scope immediately after you are setting it to > Nothing, so that's unnecessary. Excessive setting objects to Nothing is a > holdover from classic VB (and even there it's not required as much as > people > think). Also, setting it Nothing in that method does not remove the > reference in the calling method - but even there it's not practical unless > your calling method is so long that you're worried about encouraging > garbage > collection as soon as possible (even then, "Using" is a more direct > approach > if that's your concern). > > So, all you're left with in your function is: > if not (ob is nothing) then > ob.close > > I think just using the Close methods on the objects directly from your > calling method is cleaner. > -- > David Anton > www.tangiblesoftwaresolutions.com > Instant C#: VB to C# converter > Instant VB: C# to VB converter > Instant C++: C# to C++ converter & VB to C++ converter > Instant J#: VB to J# converter > > > > "andreas" wrote: > >> Hi, >> I am working with the streams objects >> (filestream,streamwriter,streamreader) >> May I do or is it good programming to make a sub like : >> >> public sub Closestreams(ByRef ob as object) >> if not (ob is nothing) then >> ob.close >> ob = nothing >> end if >> end sub >> >> thanks for any response >> >> >> Michel,
I answer your question in your other reply here. AFAIK does the GC not start in the middle of a routine. That is AFAIK the only reason to start the GC by hand. This with as exception that the action in your sample is a kind of IO operation (including painting). Than I agree that it can be a reason to do as you show, however, than I would set in your sample the force of the GC. I did not see now that you did mean an IO (or operation as that). Cor Show quoteHide quote "Michel Posseth [MCP]" <M***@posseth.com> schreef in bericht news:ORrwjQ%23SGHA.4600@TK2MSFTNGP11.phx.gbl... > > Well ...... > > > It also doesn`t hurt , to use Nothing , and in a lot of MS examples i > see Nothing used even better i found some articles that state that in some > situations it might even benefit the GC to use Nothing . > > Can you clean to good in your home ??? > > and indeed as a VB6 progger i learned how to clean up my mess .... :-) > > in the example i showed in a above post for instance it is in my opinion > perfectly valid to use Nothing , as it might help in the release of the > object before the method has finished > > regards > > Michel Posseth [MCP] > > > > "David Anton" <DavidAn***@discussions.microsoft.com> schreef in bericht > news:DB6AD6BB-706A-438D-BD63-2831FFF9A043@microsoft.com... >> As Herfried says, it's pointless to set ob to Nothing - ob is just a >> parameter that goes out of scope immediately after you are setting it to >> Nothing, so that's unnecessary. Excessive setting objects to Nothing is >> a >> holdover from classic VB (and even there it's not required as much as >> people >> think). Also, setting it Nothing in that method does not remove the >> reference in the calling method - but even there it's not practical >> unless >> your calling method is so long that you're worried about encouraging >> garbage >> collection as soon as possible (even then, "Using" is a more direct >> approach >> if that's your concern). >> >> So, all you're left with in your function is: >> if not (ob is nothing) then >> ob.close >> >> I think just using the Close methods on the objects directly from your >> calling method is cleaner. >> -- >> David Anton >> www.tangiblesoftwaresolutions.com >> Instant C#: VB to C# converter >> Instant VB: C# to VB converter >> Instant C++: C# to C++ converter & VB to C++ converter >> Instant J#: VB to J# converter >> >> >> >> "andreas" wrote: >> >>> Hi, >>> I am working with the streams objects >>> (filestream,streamwriter,streamreader) >>> May I do or is it good programming to make a sub like : >>> >>> public sub Closestreams(ByRef ob as object) >>> if not (ob is nothing) then >>> ob.close >>> ob = nothing >>> end if >>> end sub >>> >>> thanks for any response >>> >>> >>> > > Cor ,
>AFAIK does the GC not start in the middle of a routine. well i wonder if it doesn`t ,,, ,, causethis code sub DoSomeStuff () Dim objVar as new foo for i as integer = 1 to 1000 if i <= 50 then objvar.PerformsomeAction if i=50 then objVar = Nothing else 'do something else except using ObjVar end if next End Sub Can be found in the best practices guidelines from MS So i guess the reasson is that objVar can be released before it runs out of scope ( before the method ends ) otherwise some writers at MS made some serious flaws in there documentation regards Michel Posseth [MCP] Show quoteHide quote "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> wrote in message news:OvsjH%23%23SGHA.4976@TK2MSFTNGP11.phx.gbl... > Michel, > > I answer your question in your other reply here. AFAIK does the GC not > start in the middle of a routine. That is AFAIK the only reason to start > the GC by hand. This with as exception that the action in your sample is a > kind of IO operation (including painting). Than I agree that it can be a > reason to do as you show, however, than I would set in your sample the > force of the GC. I did not see now that you did mean an IO (or operation > as that). > > Cor > > > "Michel Posseth [MCP]" <M***@posseth.com> schreef in bericht > news:ORrwjQ%23SGHA.4600@TK2MSFTNGP11.phx.gbl... >> >> Well ...... >> >> >> It also doesn`t hurt , to use Nothing , and in a lot of MS examples i >> see Nothing used even better i found some articles that state that in >> some situations it might even benefit the GC to use Nothing . >> >> Can you clean to good in your home ??? >> >> and indeed as a VB6 progger i learned how to clean up my mess .... :-) >> >> in the example i showed in a above post for instance it is in my opinion >> perfectly valid to use Nothing , as it might help in the release of the >> object before the method has finished >> >> regards >> >> Michel Posseth [MCP] >> >> >> >> "David Anton" <DavidAn***@discussions.microsoft.com> schreef in bericht >> news:DB6AD6BB-706A-438D-BD63-2831FFF9A043@microsoft.com... >>> As Herfried says, it's pointless to set ob to Nothing - ob is just a >>> parameter that goes out of scope immediately after you are setting it to >>> Nothing, so that's unnecessary. Excessive setting objects to Nothing is >>> a >>> holdover from classic VB (and even there it's not required as much as >>> people >>> think). Also, setting it Nothing in that method does not remove the >>> reference in the calling method - but even there it's not practical >>> unless >>> your calling method is so long that you're worried about encouraging >>> garbage >>> collection as soon as possible (even then, "Using" is a more direct >>> approach >>> if that's your concern). >>> >>> So, all you're left with in your function is: >>> if not (ob is nothing) then >>> ob.close >>> >>> I think just using the Close methods on the objects directly from your >>> calling method is cleaner. >>> -- >>> David Anton >>> www.tangiblesoftwaresolutions.com >>> Instant C#: VB to C# converter >>> Instant VB: C# to VB converter >>> Instant C++: C# to C++ converter & VB to C++ converter >>> Instant J#: VB to J# converter >>> >>> >>> >>> "andreas" wrote: >>> >>>> Hi, >>>> I am working with the streams objects >>>> (filestream,streamwriter,streamreader) >>>> May I do or is it good programming to make a sub like : >>>> >>>> public sub Closestreams(ByRef ob as object) >>>> if not (ob is nothing) then >>>> ob.close >>>> ob = nothing >>>> end if >>>> end sub >>>> >>>> thanks for any response >>>> >>>> >>>> >> >> > > Michel,
If the method from objvar.PerformsomeAction is calling the GC or by instance do a show of whatever, than it works in my opinion. :-) CorShow quoteHide quote "m.posseth" <mich***@nohausystems.nl> schreef in bericht news:eK$DBmBTGHA.5656@TK2MSFTNGP11.phx.gbl... > Cor , > > >>AFAIK does the GC not start in the middle of a routine. > > well i wonder if it doesn`t ,,, ,, cause > > > this code > > sub DoSomeStuff () > Dim objVar as new foo > for i as integer = 1 to 1000 > if i <= 50 then > objvar.PerformsomeAction > if i=50 then objVar = Nothing > else > 'do something else except using ObjVar > end if > next > > End Sub > > > Can be found in the best practices guidelines from MS > > So i guess the reasson is that objVar can be released before it runs out > of scope ( before the method ends ) otherwise some writers at MS made > some serious flaws in there documentation > > > > regards > > Michel Posseth [MCP] > > > > "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> wrote in message > news:OvsjH%23%23SGHA.4976@TK2MSFTNGP11.phx.gbl... >> Michel, >> >> I answer your question in your other reply here. AFAIK does the GC not >> start in the middle of a routine. That is AFAIK the only reason to start >> the GC by hand. This with as exception that the action in your sample is >> a kind of IO operation (including painting). Than I agree that it can be >> a reason to do as you show, however, than I would set in your sample the >> force of the GC. I did not see now that you did mean an IO (or operation >> as that). >> >> Cor >> >> >> "Michel Posseth [MCP]" <M***@posseth.com> schreef in bericht >> news:ORrwjQ%23SGHA.4600@TK2MSFTNGP11.phx.gbl... >>> >>> Well ...... >>> >>> >>> It also doesn`t hurt , to use Nothing , and in a lot of MS examples i >>> see Nothing used even better i found some articles that state that in >>> some situations it might even benefit the GC to use Nothing . >>> >>> Can you clean to good in your home ??? >>> >>> and indeed as a VB6 progger i learned how to clean up my mess .... :-) >>> >>> in the example i showed in a above post for instance it is in my >>> opinion perfectly valid to use Nothing , as it might help in the release >>> of the object before the method has finished >>> >>> regards >>> >>> Michel Posseth [MCP] >>> >>> >>> >>> "David Anton" <DavidAn***@discussions.microsoft.com> schreef in bericht >>> news:DB6AD6BB-706A-438D-BD63-2831FFF9A043@microsoft.com... >>>> As Herfried says, it's pointless to set ob to Nothing - ob is just a >>>> parameter that goes out of scope immediately after you are setting it >>>> to >>>> Nothing, so that's unnecessary. Excessive setting objects to Nothing >>>> is a >>>> holdover from classic VB (and even there it's not required as much as >>>> people >>>> think). Also, setting it Nothing in that method does not remove the >>>> reference in the calling method - but even there it's not practical >>>> unless >>>> your calling method is so long that you're worried about encouraging >>>> garbage >>>> collection as soon as possible (even then, "Using" is a more direct >>>> approach >>>> if that's your concern). >>>> >>>> So, all you're left with in your function is: >>>> if not (ob is nothing) then >>>> ob.close >>>> >>>> I think just using the Close methods on the objects directly from your >>>> calling method is cleaner. >>>> -- >>>> David Anton >>>> www.tangiblesoftwaresolutions.com >>>> Instant C#: VB to C# converter >>>> Instant VB: C# to VB converter >>>> Instant C++: C# to C++ converter & VB to C++ converter >>>> Instant J#: VB to J# converter >>>> >>>> >>>> >>>> "andreas" wrote: >>>> >>>>> Hi, >>>>> I am working with the streams objects >>>>> (filestream,streamwriter,streamreader) >>>>> May I do or is it good programming to make a sub like : >>>>> >>>>> public sub Closestreams(ByRef ob as object) >>>>> if not (ob is nothing) then >>>>> ob.close >>>>> ob = nothing >>>>> end if >>>>> end sub >>>>> >>>>> thanks for any response >>>>> >>>>> >>>>> >>> >>> >> >> > > Well if i read this
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vbcon/html/vbup1029.asp I translate this " if an object is set to Nothing inside a procedure and the next line of code creates an object of the same name, the first object may not yet be destroyed " That it might or might not be destroyed at this point ,,,, so afaik the carbage collector kicks in whenever it feels that it is necesary to do so ( resources needed ) and so it becomes in my opinion again good practice to release the object as soon as you are ready with it and it makes sense to do so ( like my loop example ) . or am i missing something here ??? regards Michel Show quoteHide quote "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> wrote in message news:e4FdmyBTGHA.1576@tk2msftngp13.phx.gbl... > Michel, > > If the method from objvar.PerformsomeAction is calling the GC or by > instance do a show of whatever, than it works in my opinion. > > :-) > > Cor > > > "m.posseth" <mich***@nohausystems.nl> schreef in bericht > news:eK$DBmBTGHA.5656@TK2MSFTNGP11.phx.gbl... >> Cor , >> >> >>>AFAIK does the GC not start in the middle of a routine. >> >> well i wonder if it doesn`t ,,, ,, cause >> >> >> this code >> >> sub DoSomeStuff () >> Dim objVar as new foo >> for i as integer = 1 to 1000 >> if i <= 50 then >> objvar.PerformsomeAction >> if i=50 then objVar = Nothing >> else >> 'do something else except using ObjVar >> end if >> next >> >> End Sub >> >> >> Can be found in the best practices guidelines from MS >> >> So i guess the reasson is that objVar can be released before it runs out >> of scope ( before the method ends ) otherwise some writers at MS made >> some serious flaws in there documentation >> >> >> >> regards >> >> Michel Posseth [MCP] >> >> >> >> "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> wrote in message >> news:OvsjH%23%23SGHA.4976@TK2MSFTNGP11.phx.gbl... >>> Michel, >>> >>> I answer your question in your other reply here. AFAIK does the GC not >>> start in the middle of a routine. That is AFAIK the only reason to start >>> the GC by hand. This with as exception that the action in your sample is >>> a kind of IO operation (including painting). Than I agree that it can be >>> a reason to do as you show, however, than I would set in your sample the >>> force of the GC. I did not see now that you did mean an IO (or operation >>> as that). >>> >>> Cor >>> >>> >>> "Michel Posseth [MCP]" <M***@posseth.com> schreef in bericht >>> news:ORrwjQ%23SGHA.4600@TK2MSFTNGP11.phx.gbl... >>>> >>>> Well ...... >>>> >>>> >>>> It also doesn`t hurt , to use Nothing , and in a lot of MS examples i >>>> see Nothing used even better i found some articles that state that in >>>> some situations it might even benefit the GC to use Nothing . >>>> >>>> Can you clean to good in your home ??? >>>> >>>> and indeed as a VB6 progger i learned how to clean up my mess .... :-) >>>> >>>> in the example i showed in a above post for instance it is in my >>>> opinion perfectly valid to use Nothing , as it might help in the >>>> release of the object before the method has finished >>>> >>>> regards >>>> >>>> Michel Posseth [MCP] >>>> >>>> >>>> >>>> "David Anton" <DavidAn***@discussions.microsoft.com> schreef in bericht >>>> news:DB6AD6BB-706A-438D-BD63-2831FFF9A043@microsoft.com... >>>>> As Herfried says, it's pointless to set ob to Nothing - ob is just a >>>>> parameter that goes out of scope immediately after you are setting it >>>>> to >>>>> Nothing, so that's unnecessary. Excessive setting objects to Nothing >>>>> is a >>>>> holdover from classic VB (and even there it's not required as much as >>>>> people >>>>> think). Also, setting it Nothing in that method does not remove the >>>>> reference in the calling method - but even there it's not practical >>>>> unless >>>>> your calling method is so long that you're worried about encouraging >>>>> garbage >>>>> collection as soon as possible (even then, "Using" is a more direct >>>>> approach >>>>> if that's your concern). >>>>> >>>>> So, all you're left with in your function is: >>>>> if not (ob is nothing) then >>>>> ob.close >>>>> >>>>> I think just using the Close methods on the objects directly from your >>>>> calling method is cleaner. >>>>> -- >>>>> David Anton >>>>> www.tangiblesoftwaresolutions.com >>>>> Instant C#: VB to C# converter >>>>> Instant VB: C# to VB converter >>>>> Instant C++: C# to C++ converter & VB to C++ converter >>>>> Instant J#: VB to J# converter >>>>> >>>>> >>>>> >>>>> "andreas" wrote: >>>>> >>>>>> Hi, >>>>>> I am working with the streams objects >>>>>> (filestream,streamwriter,streamreader) >>>>>> May I do or is it good programming to make a sub like : >>>>>> >>>>>> public sub Closestreams(ByRef ob as object) >>>>>> if not (ob is nothing) then >>>>>> ob.close >>>>>> ob = nothing >>>>>> end if >>>>>> end sub >>>>>> >>>>>> thanks for any response >>>>>> >>>>>> >>>>>> >>>> >>>> >>> >>> >> >> > > Michael,
Michael, and so it becomes in my opinion again good practice to release the object as soon as you are ready with it What is the good practise in this, somebody who started with this fairytale As long as there is more than enough resource and memory there is in my opinion not any need to clean the older up. It is not your desktop it is your garbage. You only need to put it at the door when there is not enough room more and/or that you are unsure if there is enough room until the next garbage is collected by the garbageman. Cor Show quoteHide quote > > > or am i missing something here ??? > > > regards > > Michel > > > > > > > > "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> wrote in message > news:e4FdmyBTGHA.1576@tk2msftngp13.phx.gbl... >> Michel, >> >> If the method from objvar.PerformsomeAction is calling the GC or by >> instance do a show of whatever, than it works in my opinion. >> >> :-) >> >> Cor >> >> >> "m.posseth" <mich***@nohausystems.nl> schreef in bericht >> news:eK$DBmBTGHA.5656@TK2MSFTNGP11.phx.gbl... >>> Cor , >>> >>> >>>>AFAIK does the GC not start in the middle of a routine. >>> >>> well i wonder if it doesn`t ,,, ,, cause >>> >>> >>> this code >>> >>> sub DoSomeStuff () >>> Dim objVar as new foo >>> for i as integer = 1 to 1000 >>> if i <= 50 then >>> objvar.PerformsomeAction >>> if i=50 then objVar = Nothing >>> else >>> 'do something else except using ObjVar >>> end if >>> next >>> >>> End Sub >>> >>> >>> Can be found in the best practices guidelines from MS >>> >>> So i guess the reasson is that objVar can be released before it runs out >>> of scope ( before the method ends ) otherwise some writers at MS made >>> some serious flaws in there documentation >>> >>> >>> >>> regards >>> >>> Michel Posseth [MCP] >>> >>> >>> >>> "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> wrote in message >>> news:OvsjH%23%23SGHA.4976@TK2MSFTNGP11.phx.gbl... >>>> Michel, >>>> >>>> I answer your question in your other reply here. AFAIK does the GC not >>>> start in the middle of a routine. That is AFAIK the only reason to >>>> start the GC by hand. This with as exception that the action in your >>>> sample is a kind of IO operation (including painting). Than I agree >>>> that it can be a reason to do as you show, however, than I would set in >>>> your sample the force of the GC. I did not see now that you did mean an >>>> IO (or operation as that). >>>> >>>> Cor >>>> >>>> >>>> "Michel Posseth [MCP]" <M***@posseth.com> schreef in bericht >>>> news:ORrwjQ%23SGHA.4600@TK2MSFTNGP11.phx.gbl... >>>>> >>>>> Well ...... >>>>> >>>>> >>>>> It also doesn`t hurt , to use Nothing , and in a lot of MS examples >>>>> i see Nothing used even better i found some articles that state that >>>>> in some situations it might even benefit the GC to use Nothing . >>>>> >>>>> Can you clean to good in your home ??? >>>>> >>>>> and indeed as a VB6 progger i learned how to clean up my mess .... >>>>> :-) >>>>> >>>>> in the example i showed in a above post for instance it is in my >>>>> opinion perfectly valid to use Nothing , as it might help in the >>>>> release of the object before the method has finished >>>>> >>>>> regards >>>>> >>>>> Michel Posseth [MCP] >>>>> >>>>> >>>>> >>>>> "David Anton" <DavidAn***@discussions.microsoft.com> schreef in >>>>> bericht news:DB6AD6BB-706A-438D-BD63-2831FFF9A043@microsoft.com... >>>>>> As Herfried says, it's pointless to set ob to Nothing - ob is just a >>>>>> parameter that goes out of scope immediately after you are setting it >>>>>> to >>>>>> Nothing, so that's unnecessary. Excessive setting objects to Nothing >>>>>> is a >>>>>> holdover from classic VB (and even there it's not required as much as >>>>>> people >>>>>> think). Also, setting it Nothing in that method does not remove the >>>>>> reference in the calling method - but even there it's not practical >>>>>> unless >>>>>> your calling method is so long that you're worried about encouraging >>>>>> garbage >>>>>> collection as soon as possible (even then, "Using" is a more direct >>>>>> approach >>>>>> if that's your concern). >>>>>> >>>>>> So, all you're left with in your function is: >>>>>> if not (ob is nothing) then >>>>>> ob.close >>>>>> >>>>>> I think just using the Close methods on the objects directly from >>>>>> your >>>>>> calling method is cleaner. >>>>>> -- >>>>>> David Anton >>>>>> www.tangiblesoftwaresolutions.com >>>>>> Instant C#: VB to C# converter >>>>>> Instant VB: C# to VB converter >>>>>> Instant C++: C# to C++ converter & VB to C++ converter >>>>>> Instant J#: VB to J# converter >>>>>> >>>>>> >>>>>> >>>>>> "andreas" wrote: >>>>>> >>>>>>> Hi, >>>>>>> I am working with the streams objects >>>>>>> (filestream,streamwriter,streamreader) >>>>>>> May I do or is it good programming to make a sub like : >>>>>>> >>>>>>> public sub Closestreams(ByRef ob as object) >>>>>>> if not (ob is nothing) then >>>>>>> ob.close >>>>>>> ob = nothing >>>>>>> end if >>>>>>> end sub >>>>>>> >>>>>>> thanks for any response >>>>>>> >>>>>>> >>>>>>> >>>>> >>>>> >>>> >>>> >>> >>> >> >> > > Michael,
Before somebody thinks that I find it good practise this was in the message from Michael > What is the good practise in this, somebody who started with this fairytale> and so it becomes in my opinion again good practice to release the object > as soon as you are ready with it > As long as there is more than enough resource and memory there is in my opinion not any need to clean the older up. It is not your desktop it is your garbage. You only need to put it at the door when there is not enough room more and/or that you are unsure if there is enough room until the next garbage is collected by the garbageman. :-) CorShow quoteHide quote >> >> >> or am i missing something here ??? >> >> >> regards >> >> Michel >> >> >> >> >> >> >> >> "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> wrote in message >> news:e4FdmyBTGHA.1576@tk2msftngp13.phx.gbl... >>> Michel, >>> >>> If the method from objvar.PerformsomeAction is calling the GC or by >>> instance do a show of whatever, than it works in my opinion. >>> >>> :-) >>> >>> Cor >>> >>> >>> "m.posseth" <mich***@nohausystems.nl> schreef in bericht >>> news:eK$DBmBTGHA.5656@TK2MSFTNGP11.phx.gbl... >>>> Cor , >>>> >>>> >>>>>AFAIK does the GC not start in the middle of a routine. >>>> >>>> well i wonder if it doesn`t ,,, ,, cause >>>> >>>> >>>> this code >>>> >>>> sub DoSomeStuff () >>>> Dim objVar as new foo >>>> for i as integer = 1 to 1000 >>>> if i <= 50 then >>>> objvar.PerformsomeAction >>>> if i=50 then objVar = Nothing >>>> else >>>> 'do something else except using ObjVar >>>> end if >>>> next >>>> >>>> End Sub >>>> >>>> >>>> Can be found in the best practices guidelines from MS >>>> >>>> So i guess the reasson is that objVar can be released before it runs >>>> out of scope ( before the method ends ) otherwise some writers at MS >>>> made some serious flaws in there documentation >>>> >>>> >>>> >>>> regards >>>> >>>> Michel Posseth [MCP] >>>> >>>> >>>> >>>> "Cor Ligthert [MVP]" <notmyfirstn***@planet.nl> wrote in message >>>> news:OvsjH%23%23SGHA.4976@TK2MSFTNGP11.phx.gbl... >>>>> Michel, >>>>> >>>>> I answer your question in your other reply here. AFAIK does the GC not >>>>> start in the middle of a routine. That is AFAIK the only reason to >>>>> start the GC by hand. This with as exception that the action in your >>>>> sample is a kind of IO operation (including painting). Than I agree >>>>> that it can be a reason to do as you show, however, than I would set >>>>> in your sample the force of the GC. I did not see now that you did >>>>> mean an IO (or operation as that). >>>>> >>>>> Cor >>>>> >>>>> >>>>> "Michel Posseth [MCP]" <M***@posseth.com> schreef in bericht >>>>> news:ORrwjQ%23SGHA.4600@TK2MSFTNGP11.phx.gbl... >>>>>> >>>>>> Well ...... >>>>>> >>>>>> >>>>>> It also doesn`t hurt , to use Nothing , and in a lot of MS examples >>>>>> i see Nothing used even better i found some articles that state that >>>>>> in some situations it might even benefit the GC to use Nothing . >>>>>> >>>>>> Can you clean to good in your home ??? >>>>>> >>>>>> and indeed as a VB6 progger i learned how to clean up my mess .... >>>>>> :-) >>>>>> >>>>>> in the example i showed in a above post for instance it is in my >>>>>> opinion perfectly valid to use Nothing , as it might help in the >>>>>> release of the object before the method has finished >>>>>> >>>>>> regards >>>>>> >>>>>> Michel Posseth [MCP] >>>>>> >>>>>> >>>>>> >>>>>> "David Anton" <DavidAn***@discussions.microsoft.com> schreef in >>>>>> bericht news:DB6AD6BB-706A-438D-BD63-2831FFF9A043@microsoft.com... >>>>>>> As Herfried says, it's pointless to set ob to Nothing - ob is just a >>>>>>> parameter that goes out of scope immediately after you are setting >>>>>>> it to >>>>>>> Nothing, so that's unnecessary. Excessive setting objects to >>>>>>> Nothing is a >>>>>>> holdover from classic VB (and even there it's not required as much >>>>>>> as people >>>>>>> think). Also, setting it Nothing in that method does not remove the >>>>>>> reference in the calling method - but even there it's not practical >>>>>>> unless >>>>>>> your calling method is so long that you're worried about encouraging >>>>>>> garbage >>>>>>> collection as soon as possible (even then, "Using" is a more direct >>>>>>> approach >>>>>>> if that's your concern). >>>>>>> >>>>>>> So, all you're left with in your function is: >>>>>>> if not (ob is nothing) then >>>>>>> ob.close >>>>>>> >>>>>>> I think just using the Close methods on the objects directly from >>>>>>> your >>>>>>> calling method is cleaner. >>>>>>> -- >>>>>>> David Anton >>>>>>> www.tangiblesoftwaresolutions.com >>>>>>> Instant C#: VB to C# converter >>>>>>> Instant VB: C# to VB converter >>>>>>> Instant C++: C# to C++ converter & VB to C++ converter >>>>>>> Instant J#: VB to J# converter >>>>>>> >>>>>>> >>>>>>> >>>>>>> "andreas" wrote: >>>>>>> >>>>>>>> Hi, >>>>>>>> I am working with the streams objects >>>>>>>> (filestream,streamwriter,streamreader) >>>>>>>> May I do or is it good programming to make a sub like : >>>>>>>> >>>>>>>> public sub Closestreams(ByRef ob as object) >>>>>>>> if not (ob is nothing) then >>>>>>>> ob.close >>>>>>>> ob = nothing >>>>>>>> end if >>>>>>>> end sub >>>>>>>> >>>>>>>> thanks for any response >>>>>>>> >>>>>>>> >>>>>>>> >>>>>> >>>>>> >>>>> >>>>> >>>> >>>> >>> >>> >> >> > > Yes - I said that if you're interested in encouraging garbage collection as
soon as possible then do that (or better yet, use 'Using'). Note that setting to Nothing doesn't trigger garbage collection - it just makes it eligible if no other references to the object exist. However, to set a local or parameter to Nothing as the last line before it goes out of scope or anywhere for a short-lived local is pointless - an object is eligible for garbage collection when it goes out of scope, so why set to Nothing immediately before going out of scope? That is totally pointless. Also, the original poster assumed that this would affect the argument passed in the calling routine - no way! Setting a parameter to Nothing doesn't set the original argument to Nothing. -- Show quoteHide quoteDavid Anton www.tangiblesoftwaresolutions.com Instant C#: VB to C# converter Instant VB: C# to VB converter Instant C++: C# to C++ converter & VB to C++ converter Instant J#: VB to J# converter "Michel Posseth [MCP]" wrote: > > Well ...... > > > It also doesn`t hurt , to use Nothing , and in a lot of MS examples i see > Nothing used even better i found some articles that state that in some > situations it might even benefit the GC to use Nothing . > > Can you clean to good in your home ??? > > and indeed as a VB6 progger i learned how to clean up my mess .... :-) > > in the example i showed in a above post for instance it is in my opinion > perfectly valid to use Nothing , as it might help in the release of the > object before the method has finished > > regards > > Michel Posseth [MCP] > > > > "David Anton" <DavidAn***@discussions.microsoft.com> schreef in bericht > news:DB6AD6BB-706A-438D-BD63-2831FFF9A043@microsoft.com... > > As Herfried says, it's pointless to set ob to Nothing - ob is just a > > parameter that goes out of scope immediately after you are setting it to > > Nothing, so that's unnecessary. Excessive setting objects to Nothing is a > > holdover from classic VB (and even there it's not required as much as > > people > > think). Also, setting it Nothing in that method does not remove the > > reference in the calling method - but even there it's not practical unless > > your calling method is so long that you're worried about encouraging > > garbage > > collection as soon as possible (even then, "Using" is a more direct > > approach > > if that's your concern). > > > > So, all you're left with in your function is: > > if not (ob is nothing) then > > ob.close > > > > I think just using the Close methods on the objects directly from your > > calling method is cleaner. > > -- > > David Anton > > www.tangiblesoftwaresolutions.com > > Instant C#: VB to C# converter > > Instant VB: C# to VB converter > > Instant C++: C# to C++ converter & VB to C++ converter > > Instant J#: VB to J# converter > > > > > > > > "andreas" wrote: > > > >> Hi, > >> I am working with the streams objects > >> (filestream,streamwriter,streamreader) > >> May I do or is it good programming to make a sub like : > >> > >> public sub Closestreams(ByRef ob as object) > >> if not (ob is nothing) then > >> ob.close > >> ob = nothing > >> end if > >> end sub > >> > >> thanks for any response > >> > >> > >> > > > Another way to explain the futility of the original "ob = Nothing" is that
all you are doing anytime you set an object to Nothing is telling the compiler that "I'm done with this reference". Why would you need to state this for a local or parameter as the last line of a short-lived routine? It's an example of coding by rote - not understanding the purpose of the statement. It was necessary I think during the pre-SP1 phase of VB4 - there was a bug which prevented the cleanup of local objects when going out of scope, but that's ancient history. -- Show quoteHide quoteDavid Anton www.tangiblesoftwaresolutions.com Instant C#: VB to C# converter Instant VB: C# to VB converter Instant C++: C# to C++ converter & VB to C++ converter Instant J#: VB to J# converter "Michel Posseth [MCP]" wrote: > > Well ...... > > > It also doesn`t hurt , to use Nothing , and in a lot of MS examples i see > Nothing used even better i found some articles that state that in some > situations it might even benefit the GC to use Nothing . > > Can you clean to good in your home ??? > > and indeed as a VB6 progger i learned how to clean up my mess .... :-) > > in the example i showed in a above post for instance it is in my opinion > perfectly valid to use Nothing , as it might help in the release of the > object before the method has finished > > regards > > Michel Posseth [MCP] > > > > "David Anton" <DavidAn***@discussions.microsoft.com> schreef in bericht > news:DB6AD6BB-706A-438D-BD63-2831FFF9A043@microsoft.com... > > As Herfried says, it's pointless to set ob to Nothing - ob is just a > > parameter that goes out of scope immediately after you are setting it to > > Nothing, so that's unnecessary. Excessive setting objects to Nothing is a > > holdover from classic VB (and even there it's not required as much as > > people > > think). Also, setting it Nothing in that method does not remove the > > reference in the calling method - but even there it's not practical unless > > your calling method is so long that you're worried about encouraging > > garbage > > collection as soon as possible (even then, "Using" is a more direct > > approach > > if that's your concern). > > > > So, all you're left with in your function is: > > if not (ob is nothing) then > > ob.close > > > > I think just using the Close methods on the objects directly from your > > calling method is cleaner. > > -- > > David Anton > > www.tangiblesoftwaresolutions.com > > Instant C#: VB to C# converter > > Instant VB: C# to VB converter > > Instant C++: C# to C++ converter & VB to C++ converter > > Instant J#: VB to J# converter > > > > > > > > "andreas" wrote: > > > >> Hi, > >> I am working with the streams objects > >> (filestream,streamwriter,streamreader) > >> May I do or is it good programming to make a sub like : > >> > >> public sub Closestreams(ByRef ob as object) > >> if not (ob is nothing) then > >> ob.close > >> ob = nothing > >> end if > >> end sub > >> > >> thanks for any response > >> > >> > >> > > > Thanks David for your explanation, I hope others people agree because the
keywords close, dispose, finalyse, nothing were a litle confusing to me (and so are sometimes the articles) Show quoteHide quote "David Anton" <DavidAn***@discussions.microsoft.com> schreef in bericht news:8BDC984A-266E-482A-9646-56281968B6E9@microsoft.com... > Another way to explain the futility of the original "ob = Nothing" is that > all you are doing anytime you set an object to Nothing is telling the > compiler that "I'm done with this reference". Why would you need to state > this for a local or parameter as the last line of a short-lived routine? > It's an example of coding by rote - not understanding the purpose of the > statement. > It was necessary I think during the pre-SP1 phase of VB4 - there was a bug > which prevented the cleanup of local objects when going out of scope, but > that's ancient history. > -- > David Anton > www.tangiblesoftwaresolutions.com > Instant C#: VB to C# converter > Instant VB: C# to VB converter > Instant C++: C# to C++ converter & VB to C++ converter > Instant J#: VB to J# converter > > > > "Michel Posseth [MCP]" wrote: > > > > > Well ...... > > > > > > It also doesn`t hurt , to use Nothing , and in a lot of MS examples i see > > Nothing used even better i found some articles that state that in some > > situations it might even benefit the GC to use Nothing . > > > > Can you clean to good in your home ??? > > > > and indeed as a VB6 progger i learned how to clean up my mess .... :-) > > > > in the example i showed in a above post for instance it is in my opinion > > perfectly valid to use Nothing , as it might help in the release of the > > object before the method has finished > > > > regards > > > > Michel Posseth [MCP] > > > > > > > > "David Anton" <DavidAn***@discussions.microsoft.com> schreef in bericht > > news:DB6AD6BB-706A-438D-BD63-2831FFF9A043@microsoft.com... > > > As Herfried says, it's pointless to set ob to Nothing - ob is just a > > > parameter that goes out of scope immediately after you are setting it to > > > Nothing, so that's unnecessary. Excessive setting objects to Nothing is a > > > holdover from classic VB (and even there it's not required as much as > > > people > > > think). Also, setting it Nothing in that method does not remove the > > > reference in the calling method - but even there it's not practical unless > > > your calling method is so long that you're worried about encouraging > > > garbage > > > collection as soon as possible (even then, "Using" is a more direct > > > approach > > > if that's your concern). > > > > > > So, all you're left with in your function is: > > > if not (ob is nothing) then > > > ob.close > > > > > > I think just using the Close methods on the objects directly from your > > > calling method is cleaner. > > > -- > > > David Anton > > > www.tangiblesoftwaresolutions.com > > > Instant C#: VB to C# converter > > > Instant VB: C# to VB converter > > > Instant C++: C# to C++ converter & VB to C++ converter > > > Instant J#: VB to J# converter > > > > > > > > > > > > "andreas" wrote: > > > > > >> Hi, > > >> I am working with the streams objects > > >> (filestream,streamwriter,streamreader) > > >> May I do or is it good programming to make a sub like : > > >> > > >> public sub Closestreams(ByRef ob as object) > > >> if not (ob is nothing) then > > >> ob.close > > >> ob = nothing > > >> end if > > >> end sub > > >> > > >> thanks for any response > > >> > > >> > > >> > > > > > > > I am working with the streams objects (filestream,streamwriter,streamreader) I think I see what you are trying to do. You want Closestreams to be a > May I do or is it good programming to make a sub like : > > public sub Closestreams(ByRef ob as object) > if not (ob is nothing) then > ob.close > ob = nothing > end if > end sub general purpose closer / object destroyer for streams. Because of late binding, it would also work for other objects that provide close (eg WebResponse). Because of this and the variety of streams, you want ob as object. With ByRef ob, the sub will also destroy the reference to the object, and that may be important if the reference is shared or is defined in a module. Well, I don't like this style of coding. My bias is heavily toward early binding. If all you plan to do is ob.close and ob=nothing, then I would do these operations inline. In many cases, as others have pointed out, the caller's ob may be about to go out of scope, so ob=nothing is not needed. When a local object variable is instantiated in a sub/function, I like to destroy it in the same place in conformance with the documentation. In this way, months from now, someone can read the code, refer to the documentation, and see that all is well. So far, I don't see any good reason for what you proposed. I could speculate that you plan to have a similar general purpose opener to go with your closer, and maybe you want both functions to do more than you have shown so far (eg keep book on open resources, block if a resource is busy, whatever). But you haven't indicated anything like this. So, as you posed the question, I'm against it. Yes, you have seen what I was trying to do
And thanks for the advice, I suppose the other readers/writers agree. "AMercer" <AMer***@discussions.microsoft.com> schreef in bericht (filestream,streamwriter,streamreader)news:8F4ECED0-93BE-4BF8-B0CB-C210207B8505@microsoft.com... > > I am working with the streams objects Show quoteHide quote > > May I do or is it good programming to make a sub like : > > > > public sub Closestreams(ByRef ob as object) > > if not (ob is nothing) then > > ob.close > > ob = nothing > > end if > > end sub > > I think I see what you are trying to do. You want Closestreams to be a > general purpose closer / object destroyer for streams. Because of late > binding, it would also work for other objects that provide close (eg > WebResponse). Because of this and the variety of streams, you want ob as > object. With ByRef ob, the sub will also destroy the reference to the > object, and that may be important if the reference is shared or is defined in > a module. > > Well, I don't like this style of coding. My bias is heavily toward early > binding. If all you plan to do is ob.close and ob=nothing, then I would do > these operations inline. In many cases, as others have pointed out, the > caller's ob may be about to go out of scope, so ob=nothing is not needed. > When a local object variable is instantiated in a sub/function, I like to > destroy it in the same place in conformance with the documentation. In this > way, months from now, someone can read the code, refer to the documentation, > and see that all is well. > > So far, I don't see any good reason for what you proposed. I could > speculate that you plan to have a similar general purpose opener to go with > your closer, and maybe you want both functions to do more than you have shown > so far (eg keep book on open resources, block if a resource is busy, > whatever). But you haven't indicated anything like this. So, as you posed > the question, I'm against it. > 
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