Comparing Type with GenericType to determine if a type is derived from a generic type where the generic argument type is unknown.

gistfile1.cs

    [TestClass]
    public class UnitTest1
    {
        [TestMethod]
        public void TestMethod1()
        {
            Assert.IsTrue(typeof(Foo<>).IsAssignableFrom(typeof(Bar)));  // fails
        }

        [TestMethod]
        public void TestIsSubClassOfRaw()
        {
            Assert.IsTrue(IsSubclassOfRawGeneric(typeof(Foo<>), typeof(Bar)));  // passes
        }

        [TestMethod]
        public void GetGenericTypeDef()
        {
            Assert.AreEqual(typeof(Foo<>), typeof(Bar).BaseType.GetGenericTypeDefinition());   // passes
        }

        [TestMethod]
        public void IsSubClassBasic()
        {
            Assert.IsTrue(typeof(Bar).IsSubclassOf(typeof(Foo<>)));  // fails
        }

        static bool IsSubclassOfRawGeneric(Type generic, Type toCheck)
        {
          //method borrowed from StackOverflow question http://stackoverflow.com/a/457708/117428 
            while (toCheck != null && toCheck != typeof(object))
            {
                var cur = toCheck.IsGenericType ? toCheck.GetGenericTypeDefinition() : toCheck;
                if (generic == cur)
                {
                    return true;
                }
                toCheck = toCheck.BaseType;
            }
            return false;
        }
    }

    internal class Bar : Foo<string>
    {        
    }

    internal class Foo<T>
    {        
    }