Collection of Objects inside Custom Class

[Timbermar]

I'm sure there is a very simple solution to this problem, I just cannot seem to get my head around it. How can I expose methods or properties of an object inside a collection as part of another object. Let me give you a real world example:

Class A has properties Prop1, Prop2 and Prop3; and just one method, Method1
Class B has its own properties, Prop4 and Prop5, and also one method, Method2

Now, I want Prop1 to be a collection for Class B objects. Using a collection type I can add new objects to Prop1, but I cannot access Prop4, Prop5 or Method2 directly...

I hope this all makes sense, please let me know if you need more details. I'm sure I've just missed something simple....

 

[gpoch]

I think I understand what your doing and I didn't have a problem accessing the method and props. Here is the code I used.

Classes

[SIZE=2][COLOR=#0000ff]Public [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]Class[/COLOR][/SIZE][SIZE=2] ClassA[/SIZE]
 
[SIZE=2][COLOR=#0000ff]Private[/COLOR][/SIZE][SIZE=2] _prop1 [/SIZE][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]New[/COLOR][/SIZE][SIZE=2] List([/SIZE][SIZE=2][COLOR=#0000ff]Of[/COLOR][/SIZE][SIZE=2] ClassB)[/SIZE]
 
[SIZE=2][COLOR=#0000ff]Public [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]Property[/COLOR][/SIZE][SIZE=2] Prop1() [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] List([/SIZE][SIZE=2][COLOR=#0000ff]Of[/COLOR][/SIZE][SIZE=2] ClassB)[/SIZE]
[SIZE=2][COLOR=#0000ff]Get[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff]Return[/COLOR][/SIZE][SIZE=2] _prop1[/SIZE]
[SIZE=2][COLOR=#0000ff]End [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]Get[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff]Set[/COLOR][/SIZE][SIZE=2]([/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] value [/SIZE][SIZE=2][COLOR=#0000ff]As[/COLOR][/SIZE][SIZE=2] List([/SIZE][SIZE=2][COLOR=#0000ff]Of[/COLOR][/SIZE][SIZE=2] ClassB))[/SIZE]
[SIZE=2]_prop1 = value[/SIZE]
[SIZE=2][COLOR=#0000ff]End [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]Set[/COLOR][/SIZE]
 
[SIZE=2][COLOR=#0000ff]End [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]Property[/COLOR][/SIZE]
 
[SIZE=2][COLOR=#0000ff]End [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]Class[/COLOR][/SIZE]
 
[SIZE=2][COLOR=#0000ff]Public [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]Class[/COLOR][/SIZE][SIZE=2] ClassB[/SIZE]
 
[SIZE=2][COLOR=#0000ff]Private[/COLOR][/SIZE][SIZE=2] _prop4 [/SIZE][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]String[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff]Private[/COLOR][/SIZE][SIZE=2] _prop5 [/SIZE][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]String[/COLOR][/SIZE]
 
[SIZE=2][COLOR=#0000ff]Public [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]Property[/COLOR][/SIZE][SIZE=2] prop4() [/SIZE][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]String[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff]Get[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff]Return[/COLOR][/SIZE][SIZE=2] _prop4[/SIZE]
[SIZE=2][COLOR=#0000ff]End [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]Get[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff]Set[/COLOR][/SIZE][SIZE=2]([/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] value [/SIZE][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]String[/COLOR][/SIZE][SIZE=2])[/SIZE]
[SIZE=2]_prop4 = value[/SIZE]
[SIZE=2][COLOR=#0000ff]End [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]Set[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff]End [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]Property[/COLOR][/SIZE]
 
[SIZE=2][COLOR=#0000ff]Public [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]Property[/COLOR][/SIZE][SIZE=2] prop5() [/SIZE][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]String[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff]Get[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff]Return[/COLOR][/SIZE][SIZE=2] _prop5[/SIZE]
[SIZE=2][COLOR=#0000ff]End [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]Get[/COLOR][/SIZE]
[SIZE=2][COLOR=#0000ff]Set[/COLOR][/SIZE][SIZE=2]([/SIZE][SIZE=2][COLOR=#0000ff]ByVal[/COLOR][/SIZE][SIZE=2] value [/SIZE][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]String[/COLOR][/SIZE][SIZE=2])[/SIZE]
[SIZE=2]_prop5 = value[/SIZE]
[SIZE=2][COLOR=#0000ff]End [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]Set[/COLOR][/SIZE]
 
[SIZE=2][COLOR=#0000ff]End [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]Property[/COLOR][/SIZE]
 
[SIZE=2][COLOR=#0000ff]Public [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]Sub[/COLOR][/SIZE][SIZE=2] Method2()[/SIZE]
[SIZE=2][COLOR=#0000ff]End [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]Sub[/COLOR][/SIZE]
 
[SIZE=2][COLOR=#0000ff]End [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]Class[/COLOR][/SIZE]

and on the form

[SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] objA [/SIZE][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]New[/COLOR][/SIZE][SIZE=2] ClassA[/SIZE]
[SIZE=2][COLOR=#0000ff]Dim[/COLOR][/SIZE][SIZE=2] objB [/SIZE][SIZE=2][COLOR=#0000ff]As [/COLOR][/SIZE][SIZE=2][COLOR=#0000ff]New[/COLOR][/SIZE][SIZE=2] ClassB[/SIZE]
[SIZE=2]objB.prop4 = [/SIZE][SIZE=2][COLOR=#800000]"hello"[/COLOR][/SIZE]
[SIZE=2]objA.Prop1.Add(objB)[/SIZE]
[SIZE=2][COLOR=#0000ff]Me[/COLOR][/SIZE][SIZE=2].Text = objA.Prop1.Item(0).prop4[/SIZE]

 

[Timbermar]

I had no idea....

That was my problem, I didn't know of the "(of object)" code. What exactly is a difference between a list and an arraylist, or collection? Thanks again.

 

[vis781]

You need to look into System.Collections.Generic and generics in general. New in .Net 2.0 the generic thing practically will do away with passing anything as an object. An arraylist uses system.object because it has to be able to accept any type in the framework this incurrs a lot of boxing and increased overhead while processing. However the generics has optimized this performance bottleneck in the framework. Check it out you'll probably find that you'll use it quite a bit.