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Groups > comp.lang.basic.visual.misc > #817

Re: What is a class?

From GS <gs@somewhere.net>
Newsgroups comp.lang.basic.visual.misc
Subject Re: What is a class?
Date 2012-02-26 14:23 -0500
Organization A noiseless patient Spider
Message-ID <jie0sp$ehn$1@dont-email.me> (permalink)
References (5 earlier) <XnsA004CD148B656auricauricauricauric@88.198.244.100> <cLCdnTOc3IH0NdTSnZ2dnUVZ_tudnZ2d@giganews.com> <jicag2$87f$1@dont-email.me> <5odjk75idm6fgl98vbmabap2djd38nvum5@4ax.com> <jicvv9$nth$1@dont-email.me>

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Helmut_Meukel pretended :
> ralph wrote:
>> On Sat, 25 Feb 2012 22:55:37 -0500, GS <gs@somewhere.net> wrote:
>> 
>>> I thought that the object created by "Dim As New" existed until the 
>>> exit from the scope they were created in. So...
>>> 
>>> In a procedure: (local scope)
>>> Dim colItems As New Collection
>>> ..lives for the entire procedure if not explicitly destroyed beforhand.
>>> 
>> 
>> ... But you can not "explicitly" destroy the collection object.
>> You can clear the contents but never get rid of the object until the
>> object reference goes out of scope.
>> 
>
> Hmm, I thought even if you created an object using
>    Dim Duck As New Monster
> you can explicitely destroy that object, e.g.
>    Set Duck = Nothing
> But *any* explicitely or implicitely reference - not only the test
> "Is Nothing" will create a new instance of the object if it doesn't
> exist.
> This will look like you only cleared the contents, but it was destroyed
> actually.
>
> You can't always have an object locally to the subroutine and if the
> object is explicitely destroyed in another subroutine, then any further
> reference e.g.
>    if Duck.Weight > 2000 then 'weight in gramms
> will automagically recreate a new instance of Duck with its default
> values. Your program will be unaware of this and happily work with the
> new Duck.
>
> In small routines, creating local objects using
>  Dim MyObject As New AnObject
> will work without problems, but if you get the habit of using this
> construct, chances are you'll use it everywhere and finally it will
> bite you.
>
> Helmut.

Normally, I practice the follow self-made programming rules:

  "Anything we leave to VB to do by 'implicity' will ALWAYS require
  extra processing on VB's part"

  "Any object 'implicity' created should be 'implicitly' destroyed"

  "Any object 'explicitly' created should be 'explicitly' destroyed"

  "Any object that needs to be reused should ALWAYS be 'explicitly'
  created AND 'explicitly' destroyed when done with each usage"

Adhering to these has never got me into trouble. I do use "Dim As New" 
on occasion in local scope only. I'm not an advocate of not using this 
VB feature because it exists for a reason and it certainly is useful in 
appropriate circumstances. Since I'm a 'creature of habit' to an 
obssesive degree, there's not likely a chance I would use "Dim As New" 
in unappropriate circumstances.<g>

-- 
Garry

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Thread

What is a class? Peter Nolan <peter.nolan40@gmail.com> - 2012-02-24 04:02 -0800
  Re: What is a class? "Auric__" <not.my.real@email.address> - 2012-02-24 14:06 +0000
    Re: What is a class? Peter Nolan <peter.nolan40@gmail.com> - 2012-02-25 03:07 -0800
      Re: What is a class? Helmut_Meukel <Helmut_Meukel@bn-hof.invalid> - 2012-02-25 14:19 +0100
      Re: What is a class? "Auric__" <not.my.real@email.address> - 2012-02-25 21:26 +0000
        Re: What is a class? Jim Mack <no-uce-ube@mdxi.com> - 2012-02-25 18:58 -0500
          Re: What is a class? GS <gs@somewhere.net> - 2012-02-25 19:39 -0500
          Re: What is a class? "Auric__" <not.my.real@email.address> - 2012-02-26 03:09 +0000
            Re: What is a class? Jim Mack <no-uce-ube@mdxi.com> - 2012-02-25 22:35 -0500
              Re: What is a class? GS <gs@somewhere.net> - 2012-02-25 22:55 -0500
                Re: What is a class? "Farnsworth" <nospam@nospam.com> - 2012-02-25 23:27 -0500
                Re: What is a class? GS <gs@somewhere.net> - 2012-02-26 01:30 -0500
                Re: What is a class? "Auric__" <not.my.real@email.address> - 2012-02-26 04:41 +0000
                Re: What is a class? ralph <nt_consulting64@yahoo.net> - 2012-02-25 23:05 -0600
                Re: What is a class? "Henning" <computer_hero@coldmail.com> - 2012-02-26 11:24 +0100
                Re: What is a class? ralph <nt_consulting64@yahoo.net> - 2012-02-25 23:03 -0600
                Re: What is a class? GS <gs@somewhere.net> - 2012-02-26 01:26 -0500
                Re: What is a class? "Stuart McCall" <smccall@myunrealbox.com> - 2012-02-27 04:15 +0000
                Re: What is a class? ralph <nt_consulting64@yahoo.net> - 2012-02-27 00:48 -0600
                Re: What is a class? "Mayayana" <mayayana@invalid.nospam> - 2012-02-27 08:57 -0500
                Re: What is a class? "Stuart McCall" <smccall@myunrealbox.com> - 2012-02-27 19:19 +0000
                Re: What is a class? "Stuart McCall" <smccall@myunrealbox.com> - 2012-02-27 19:12 +0000
                Re: What is a class? "Bob Butler" <bob_butler@cox.invalid> - 2012-02-27 06:06 -0800
                Re: What is a class? "Stuart McCall" <smccall@myunrealbox.com> - 2012-02-27 19:24 +0000
                Re: What is a class? GS <gs@somewhere.net> - 2012-02-27 11:01 -0500
                Re: What is a class? ralph <nt_consulting64@yahoo.net> - 2012-02-27 11:07 -0600
                Re: What is a class? GS <gs@somewhere.net> - 2012-02-27 13:10 -0500
                Re: What is a class? Schmidt <sss@online.de> - 2012-02-27 19:09 +0100
                Re: What is a class? GS <gs@somewhere.net> - 2012-02-27 13:29 -0500
                Re: What is a class? GS <gs@somewhere.net> - 2012-02-27 14:43 -0500
                Re: What is a class? Schmidt <sss@online.de> - 2012-02-27 22:14 +0100
                Re: What is a class? GS <gs@somewhere.net> - 2012-02-27 16:45 -0500
                Re: What is a class? GS <gs@somewhere.net> - 2012-02-27 18:23 -0500
                Re: What is a class? GS <gs@somewhere.net> - 2012-02-27 23:26 -0500
                Re: What is a class? Schmidt <sss@online.de> - 2012-02-28 13:54 +0100
                Re: What is a class? GS <gs@somewhere.net> - 2012-02-28 08:37 -0500
                Re: What is a class? ralph <nt_consulting64@yahoo.net> - 2012-02-28 09:19 -0600
                Re: What is a class? GS <gs@somewhere.net> - 2012-02-28 10:42 -0500
                Re: What is a class? Schmidt <sss@online.de> - 2012-02-29 06:47 +0100
                Re: What is a class? GS <gs@somewhere.net> - 2012-02-29 09:39 -0500
                Re: What is a class? GS <gs@somewhere.net> - 2012-02-29 13:33 -0500
                Re: What is a class? GS <gs@somewhere.net> - 2012-02-29 14:43 -0500
                Re: What is a class? Schmidt <sss@online.de> - 2012-02-29 21:39 +0100
                Re: What is a class? GS <gs@somewhere.net> - 2012-02-29 16:15 -0500
                Re: What is a class? Schmidt <sss@online.de> - 2012-02-29 23:20 +0100
                Re: What is a class? GS <gs@somewhere.net> - 2012-02-28 00:16 -0500
                Re: What is a class? Jim Mack <no-uce-ube@mdxi.com> - 2012-02-27 13:26 -0500
                Re: What is a class? "Stuart McCall" <smccall@myunrealbox.com> - 2012-02-27 19:33 +0000
                Re: What is a class? Jim Mack <no-uce-ube@mdxi.com> - 2012-02-27 15:50 -0500
                Re: What is a class? Helmut_Meukel <Helmut_Meukel@bn-hof.invalid> - 2012-02-26 11:02 +0100
                Re: What is a class? GS <gs@somewhere.net> - 2012-02-26 14:23 -0500
                Re: What is a class? GS <gs@somewhere.net> - 2012-02-26 17:09 -0500
            Re: What is a class? ralph <nt_consulting64@yahoo.net> - 2012-02-25 22:21 -0600
              Re: What is a class? "Auric__" <not.my.real@email.address> - 2012-02-26 04:51 +0000
                Re: What is a class? ralph <nt_consulting64@yahoo.net> - 2012-02-25 23:10 -0600
        Re: What is a class? Peter Nolan <peter.nolan40@gmail.com> - 2012-02-26 04:11 -0800
          Re: What is a class? Helmut_Meukel <Helmut_Meukel@bn-hof.invalid> - 2012-02-26 16:37 +0100
          Re: What is a class? "Auric__" <not.my.real@email.address> - 2012-02-26 18:36 +0000
            Re: What is a class? ralph <nt_consulting64@yahoo.net> - 2012-02-26 14:11 -0600
            Re: What is a class? Peter Nolan <peter.nolan40@gmail.com> - 2012-02-27 03:11 -0800
              Re: What is a class? "Auric__" <not.my.real@email.address> - 2012-02-27 16:33 +0000
                Re: What is a class? Jim Mack <no-uce-ube@mdxi.com> - 2012-02-27 13:33 -0500
                Re: What is a class? Peter Nolan <peter.nolan40@gmail.com> - 2012-02-28 04:07 -0800
    Re: What is a class? Peter Nolan <peter.nolan40@gmail.com> - 2012-02-25 03:33 -0800
    Re: What is a class? Peter Nolan <peter.nolan40@gmail.com> - 2012-02-25 04:19 -0800
  Re: What is a class? "Ivar" <ivar.ekstromer000@ntlworld.com> - 2012-02-24 15:15 +0000
    Re: What is a class? GS <gs@somewhere.net> - 2012-02-24 14:52 -0500
      Re: What is a class? "Ivar" <ivar.ekstromer000@ntlworld.com> - 2012-02-24 23:10 +0000
        Re: What is a class? GS <gs@somewhere.net> - 2012-02-24 19:46 -0500
          Re: What is a class Way off Topic "Ivar" <ivar.ekstromer000@ntlworld.com> - 2012-02-25 02:20 +0000
            Re: What is a class Way off Topic GS <gs@somewhere.net> - 2012-02-25 16:57 -0500
        Re: What is a class? Helmut_Meukel <Helmut_Meukel@bn-hof.invalid> - 2012-02-25 11:36 +0100
    Re: What is a class? Peter Nolan <peter.nolan40@gmail.com> - 2012-02-25 03:35 -0800
  Re: What is a class? Jim Mack <no-uce-ube@mdxi.com> - 2012-02-24 15:23 -0500
    Re: What is a class? "Auric__" <not.my.real@email.address> - 2012-02-25 01:33 +0000
    Re: What is a class? Peter Nolan <peter.nolan40@gmail.com> - 2012-02-25 03:09 -0800
  Re: What is a class? "Mayayana" <mayayana@invalid.nospam> - 2012-02-24 20:05 -0500

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