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Re: What is a class?

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Peter Nolan machte das folgende Beispiel:
> On Feb 24, 2:06 pm, "Auric__" <not.my.r...@email.address> wrote:
>> Peter Nolan wrote:
>>> I have tried, trust me, to learn what a class is in VB and in spite of
>>> many an attempt I remain baffled and I was wondering if you could help
>>> me out. In addition to reading I have watched YouTube videos.
>>> I know that fish is a class and so a trout is an instance of the class
>>> fish. I also know that a class contains a function and data. I better
>>> leave it at that because of how confused I am about the whole thing.
>> 
>> Have you read the Wikipedia entry?
>>  http://en.wikipedia.org/wiki/Class_(computer_programming)
>> 
>> The very first sentence there might help you:
>>   a class is a construct that is used as a blueprint
>> 
>> So, it might help to think of a class as a sort of blueprint. A class
>> describes something, and when you create a new instance of a class, you're
>> using the blueprint.
>> 
>> Say you're writing a game, and you have a class called "monster". When you
>> need a new monster, you could do (for example):
>>   Dim duck As New monster
>>   duck.Health = 1
>>   duck.Strength = 1
>>   'etc.
>> ...rather than:
>>   Dim duckHealth As Integer, duckStrength As Integer 'etc.
>> 
>> --
>> I'm not evil. I'm living up to my full potential!
>
>
> Hello Auric,
>
> I haven't the faintest idea what the rest of the thread is about to do
> with For Next loops and so on.
> However can I ask you a question? Is New monster a user defined
> datatype other than the default data types like Integer and Long that
> has the values duck.Health = 1 and duck.Strength =1 It's like a more
> sophisticated type of data that really could very detailed with many
> more values. If I am making any sense here it doesn't actually mean I
> know what is going on. What simple illustrative code would describe
> monster in the first place?
> Many thanks for taking the time to explain things to me.
>
> Regards,
>
> Peter.

Hmm, I think you really should take a class in programming as Jim
suggested.

But I'll try to explain.
How would you program a library app? Just books in the library for
starters.
You could do it traditionally, store all data in arrays, e.g. Title,
Author, Publisher, date of copyright, publishing date, actual language,
original language, HC/Trade/MMPB/eBook, genre, subgenre, description, ...
or create only one UDT array named Books.

Or you could create a class named Book, with properties (Title, Author,...)
and a Books collection containing all books in the library.
To delete a book, you just remove it from the Books collection.
To add a new book you create a new instance of class Book, set the
properties to the appropriate values, e.g.
  NewBook.Author = "Poul Anderson"
  NewBook.Publisher = "Baen Books"
  NewBook.Title = "Time Patrol"
  NewBook.Genre = "SF"
  NewBook.Subgenre = "time travel"
   ...
When done you add NewBook to the Books collection.

HTH,

Helmut.

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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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