Get members from flattened interface hierarchy

Question

Possible Duplicate:
Reflecting over all properties of an interface, including inherited ones?

While trying to receive information about all methods from an interface, I first tried the following:

interface IBaseInterface
{
    void SomeMethod();
}
interface ISomeInterface : IBaseInterface {}

Type interfaceType = typeof( ISomeInterface );
BindingFlags allInstanceMembers = BindingFlags.FlattenHierarchy |
                                  BindingFlags.Instance |
                                  BindingFlags.NonPublic |
                                  BindingFlags.Public;
MethodInfo[] methods = interfaceType.GetMethods( allInstanceMembers );

This results in an empty methods array.

I believe the problem is flatten hierarchy doesn't work for interfaces, but I'm not sure. Before attempting an implementation using Type.GetInterfaceMap it would be nice if someone could confirm, or explain what I'm doing wrong.

Answer 1

FlattenHierarchy only affects static methods in concrete types:

From http://msdn.microsoft.com/en-us/library/4d848zkb.aspx:

Specify BindingFlags.FlattenHierarchy to include public and protected static members up the hierarchy; private static members in inherited classes are not included.

You will indeed have to use GetInterfaceMap() and/or simply iterate through all interfaces within the hierarchy yourself.

Answer 2

I'd recommend checking out Fasterflect, a library intended to make reflection easier and faster (the latter doesn't apply to lookups though).

To find all instance members you can simply do:

var methods = typeof(ISomeInterface).Methods( Flags.InstanceAnyVisibility );

Fasterflect will flatten the hierarchy by default, so no special code is needed to include the base interface members (lookups are recursive, object members not included).