Question

I want to instantiate a generic collection (a Dictionary in this case) but in the generic type declaration I want constraint the parameter type to more then 1 class.

Here is the example code:

I have many classes with this declaration:

public class MyClass1 : UserControl, IEspecialOptions
public class MyClass2 : UserControl, IEspecialOptions, IOtherInterface

etc.

This is what I want:

Dictionary<int, T> where T:UserControl, IEspecialOptions myDicc = new Dictionary<int, T>();

This looks very nice but don’t compile.

Do you know how to contraint the second parameter to inherate from 2 classes/interfaces?

I’m limited to .net 2.0

Thanks in advance

Answer 1

You cannot. But you can create an abstract class that both inherits UserControl and implements IEscpecialOptions and then constraint the generic parameter to be of the abstract type.