PRB: Using Reflection Without the Meta Data Permits Only Methods on the Default IDispatch Interface to Be Invoked (318664)

RESOLUTION

using System;
using System.Runtime.InteropServices;

namespace SampleApplication
{
	//The COM Server in this example is MyComCoClass, which implements a non-default
	//interface, IDerivedFromIDispatch, which is derived from IDispatch.

	// Declare IDerivedFromIDispatch as a COM interface that 
	// derives from IDispatch interface:
	[Guid("25C5B012-A7F1-4E2E-8AD8-363B31D27DE4"), 
	InterfaceType(ComInterfaceType.InterfaceIsDual)] 
	interface IDerivedFromIDispatch   // You cannot list any base interfaces here. 
	{ 
		// Note that IUnknown Interface members are NOT listed here:
		void DoStuff();

	}

	// Declare the MyComCoClass COM coclass:
	[ComImport, Guid("3754AFD8-24F4-4A2C-9857-FB990B11A204")] 
	class MyComCoClass 
	{ 
		// You cannot have any members here. 
		// Note that the C# compiler will add a default constructor
		// for you (no parameters).
	}
	
	class Class1
	{
		[STAThread]
		static void Main(string[] args)
		{
			// Create an instance of SampleApplication.
			// (Calls CoCreateInstance(3754AFD8-24F4-4A2C-9857-FB990B11A204, 
			//  NULL, CLSCTX_ALL, IID_IUnknown, 
			//  &oApplication). Returns null on failure.):
			SampleApplication.MyComCoClass oApplication = new SampleApplication.MyComCoClass();
									
			// You need to cast this so C# will know what type of object it really is.  
			SampleApplication.IDerivedFromIDispatch ci = (SampleApplication.IDerivedFromIDispatch) oApplication;

			// Call a method on coClass.
                           // DoStuff accepts no parameters and does not return a value.
			ci.DoStuff();			
		}
	}
}