Question

Has anyone ever tried to implement ICommandSource with VB?
The examples provided by Microsoft are in C#, and since VB doesn’t allow implicit implementation this interface is like inachievable in VB!!

http://msdn.microsoft.com/en-us/library/ms771361.aspx

Answer 1

It depends on what class you want to implement it on. If you’re introducing the Command, CommandParameter and CommandTarget properties in your own class (where you’re implementing the interface), you can just implement it like any other interface:

Public ReadOnly Property Command() As ICommand
  Implements ICommandSource.Command
  Get
    ' implementation goes here
  End Get
End Property

You can still use a DP for the implementation, by the way: the Implements directive is on the CLR property and does not interfere with the “do not touch” implementation of the getters and setters.

If the class you want to implement it on already has (inherited) Command, CommandParameter and CommandTarget properties, and you want the interface implementation to reuse those, you’ll need to create new properties with new names, declare them as interface implementations and back them onto the existing properties

Public ReadOnly Property ICommandSource_Command() As ICommand
  Implements ICommandSource.Command
  Get
    Return Me.Command  ' the existing implementation that can't be made implicit
  End Get
End Property