Reflecting on interfaces of a type in C#

Question

How can I reflect on the interfaces implemented by a given type (of class or interface) in .NET?

As the type being reflected on will be generic (both in the implementation sense as well as the semantic sense), it would preferable to do this without having to hardcode an Assembly name, though I realise that I can get this name from the Type class of any given type.

Answer 1

Call Type.GetInterfaces().

Answer 2

Type.GetInterfaces() only gets you declared interfaces (MSDN should have documentation that explains this). To get inherited interfaces you must do the work yourself. Something similar to:

using System;
using System.Linq;

public static IEnumerable<Type> GetAllInterfacesForType(this Type type)
{
   foreach (var interfaceType in type.GetInterfaces())
   {
       yield return interfaceType;
       foreach (var t in interfaceType.GetAllInterfacesForType())
           yield return t;
   }
}


public static IEnumerable<Type> GetUniqueInterfacesForType(this Type type)
{ return type.GetAllInterfaces().Distinct(); }

I wrote this off the cuff so sorry if it doesn't compile straight-outta-da-box.