vb.net - visual - what is msdn collection in vb
VB.NET Strong-typed collection (2)
Why don't you just use a
List(Of Foo)... It is already in VB.NET under
System.Collections.Generic. To use, simply declare as such:
Private myList As New List(Of Foo) 'Creates a Foo List' Private myIntList As New List(Of Integer) 'Creates an Integer List'
MSDN > List(T) Class (System.Collections.Generic) for more information.
I want to create a collection in VB.NET, but I only want it to accept objects of a certain type. For example, I want to create a class called "FooCollection" that acts like a collection in every way, but only accepts objects of type "Foo".
I thought I could do this using generics, using the following syntax:
Public Class FooCollection(Of type As Foo) Inherits CollectionBase ... End Class
But I get an error when I compile it that I "must implement a default accessor", so clearly there's something missing. I don't want to specify the type it accepts when I instantiate - I want the FooCollection itself to specific that it only accepts Foo objects. I've seen it done in C# with a strong-typed list, so maybe all I'm looking for is VB.NET syntax.
Thanks for your help!
EDIT: Thanks for the answer. That would do it, but I wanted to have the classtype named a certain way, I actually accomplished exactly what I was looking for with the following code:
Public Class FooCollection Inherits List(Of Foo) End Class
You needed to implement a default property for the collection like this:
Default Public Property Item(ByVal Index As Integer) As Foo Get Return CType(List.Item(Index), Foo) End Get Set(ByVal Value As Foo) List.Item(Index) = Value End Set