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Convert delegate to function pointer in Visual Studio 2005

Posted on 2006-07-18
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Last Modified: 2008-02-01
Hi,

I'm wondering if there is a way to convert delegates to function pointers in Visual Studio 2005 without making function calls through any DLL nor using the /clr:oldSyntax compiler option?

I have read the following articles, but the example codes are based on the VS2003 syntax:
    http://www.codeproject.com/managedcpp/delegate_to_callback.asp
    http://www.codeproject.com/managedcpp/unmanaged_to_managed.asp

Thanks,

James
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Question by:james567
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lakshman_ce earned 500 total points
ID: 17135441
Use Marshal::GetFunctionPointerForDelegate

Here is the sample code

#include "stdafx.h"

using namespace System;
using namespace System::Runtime::InteropServices;
delegate void myMethodDelegate( // Declares a delegate for a method that takes in an int and returns a String.
int myInt );
typedef void (*PFUNC)(Int32);

// Defines some methods to which the delegate can point.
ref class mySampleClass
{
public:

   // Defines an instance method.
   void myStringMethod( int myInt )
   {
      if ( myInt > 0 )
              Console::WriteLine("positive");

      if ( myInt < 0 )
            Console::WriteLine ("negative");
  }
};

int main()
{
   mySampleClass^ mySC = gcnew mySampleClass;
   myMethodDelegate^ myD1 = gcnew myMethodDelegate( mySC, &mySampleClass::myStringMethod );
   myD1( 5 );
   IntPtr pint = Marshal::GetFunctionPointerForDelegate(myD1);
   PFUNC pFnc = (PFUNC)pint.ToPointer();
   pFnc(5);  
}
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