(inheritance) problem with generic

[Lloyd Dupont]

I try to test the interface implemented by a generic with the simple test
below.
What puzzle me is that all 4 test return false!
Any idea why is that and how to find the IList interface from the type?

-------------
using System;
using System.Collections;
using System.Collections.Generic;

// csc /nologo Class1.cs && Class1
public class Class1
{
public static void Main()
{
List<string> ls = new List<string>();
if(ls is IList)
{
Console.WriteLine("is IList(1): " +
ls.GetType().IsSubclassOf(typeof(IList)));
Console.WriteLine("is IList(2): " +
ls.GetType().IsAssignableFrom(typeof(IList)));
Console.WriteLine("is IList(3): " +
ls.GetType().IsInstanceOfType(typeof(IList)));
Console.WriteLine("is IList(4): " +
ls.GetType().IsDefined(typeof(IList), true));
}
}
}

 

[Lau Lei Cheong]

Have you tried "Console.WriteLine(ls is IList)"?

If ls is castable to IList, the result of using "is" operator will be "true"

 

[Lloyd Dupont]

obviously you haven't looked at my example....

yep what you worte (and I wrote it too), works very well.
however when you have a Type object, it's a bit more difficult with generic.

Anyway I solved it and posted the solution

 

[Mattias Sjögren]

Console.WriteLine("is IList(2): " +
ls.GetType().IsAssignableFrom(typeof(IList)));

You're using it the wrong way around, try

Console.WriteLine("is IList(2): " +
typeof(IList).IsAssignableFrom(ls.GetType()));



Mattias

 

[Lloyd Dupont]

ooh...
aheum, indeed.....
thanks!

You're using it the wrong way around, try

Console.WriteLine("is IList(2): " +
typeof(IList).IsAssignableFrom(ls.GetType()));



Mattias