Detecting if type implements ICollection

Question

I am trying to check if a type implements the generic ICollection<T> interface, since this is a base interface for any of my generic collections.

The below code doesn't work

GetType(ICollection(Of)).IsAssignableFrom(
    objValue.GetType().GetGenericTypeDefinition())

What's a good way of detecting if a type implements a generic interface?

score 31 · Accepted Answer · answered Sep 24 '09 at 14:40

31

CustomCollection c = new CustomCollection();

bool implementICollection = c.GetType().GetInterfaces()
                            .Any(x => x.IsGenericType &&
                            x.GetGenericTypeDefinition() == typeof(ICollection<>));

answered Sep 24 '09 at 14:40

Stan R.

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This is the correct answer; I've tested it – Graviton Sep 24 '09 at 14:47

score 1 · Answer 2 · edited Aug 29 '17 at 08:22

1

An alternative to the others is the following:

if (MyObject is ICollection<T>)
  ...

Note: This will only work if T is known at compile time.

edited Aug 29 '17 at 08:22

Shimmy Weitzhandler

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answered Sep 24 '09 at 14:47

Bomlin

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Detecting if type implements ICollection

2 Answers2