Managed C++/CLI

   Form^ form2 = gcnew Form;
      
   form2->buttonSave->DialogResult = ::DialogResult::OK;
   form2->buttonCancel->DialogResult = ::DialogResult::CANCEL;
   
   form2->ShowDialog();
   
   // If I leave out the buttonSave->DialogResult and I close 
   // the form  after pushing Save button my program isn't 
   // going further here

   if ( form2->DialogResult == ::DialogResult::OK )
   {
       ...
       DataAdapter->Update(myDataSet, "DATA");
   }

System::Void buttonSave_Click(System::Object^  sender, System::EventArgs^  e) 
{
    if (this->textBox1->Text == "")
       {
	    MessageBox::Show("Field is obligated");
	    this->textBox1->Focus();
       }
       else
       {
	    this->DialogResult == ::DialogResult::OK;
	    this->Close();
       }

}

ManagedWrapper.h

	public delegate void BasicCallbackDelegate(short cmd);
	public delegate void NonBasicCallbackDelegate(array<EPClass^>^ epList);

	[StructLayoutAttribute(Sequential, CharSet = Ansi )]
	public ref struct ManagedBasicDelegateWrapper
	{
		[MarshalAsAttribute(UnmanagedType::FunctionPtr)]
		BasicCallbackDelegate^ _Delegate;
        };

	[StructLayoutAttribute(Sequential, CharSet = Ansi )]
	public ref struct ManagedNonBasicDelegateWrapper
	{
		[MarshalAsAttribute(UnmanagedType::FunctionPtr)]
		NonBasicCallbackDelegate^ _nDelegate;
        };

	public ref class ManagedWrapperClass
	{
	public:
		ManagedWrapperClass(ManagedBasiceDelegateWrapper^ cbd);
		ManagedWrapperClass(ManagedNonBasicDelegateWrapper^ cbd);
	};

ManagedWrapper.cpp

        extern class BasicPushConsumer *BasicPushConsumerObject;
        extern class NonBasicPushConsumer *NonBasicPushConsumerObject;

	ManagedWrapperClass::ManagedWrapperClass(ManagedBasicDelegateWrapper^ cbd)
	{
		gt_Callback callback;

		Marshal::StructureToPtr(cbd, safe_cast<System::IntPtr>(&callback), false);

		BasicPushConsumerObject->SetCallbackInUnmanaged(callback);
	}
	
	ManagedWrapperClass::ManagedWrapperClass(ManagedNonBasicDelegateWrapper^ cbd)
	{
		ep_Callback callback;

		Marshal::StructureToPtr(cbd, safe_cast<System::IntPtr>(&callback), false);

		NonBasicPushConsumer->SetCallbackInUnmanaged(callback);
	}

*pruned* NonBasicPushConsumer.cpp
//Unmanaged class required by CORBA

typedef void (*gt_Callback) (short cmd);
typedef void (*ep_Callback) (array<EPClass^>^ epList);

void NonBasicPushConsumer::SetCallbackInUnmanaged(ep_Callback ptr2f)
{
	scallback = ptr2f;
}

void NonBasicPushConsumer::ManagedMethodToCall(array<EPClass^>^ epList)
{
	scallback(epList); //This produces the crash in question
}

*pruned* Form1.cs

            ManagedNonBasicDelegateWrapper mcf = new ManagedNonBasicDelegateWrapper();
            mcf._epDelegate = new EntityPositionCallbackDelegate(CallbackFunction);
            ManagedWrapperClass mwc = new ManagedWrapperClass(mcf);

        public static void CallbackFunction(System.Array epList)
        {
            Console.WriteLine("CALLBACK!");
        }

public static void CallbackFunction(EPList[] epList)

    // Note:  This is for a Forms app, not a console (SUBSYSTEM:CONSOLE) app!

    [DllImport("Kernel32.dll")]
    extern int AllocConsole();

    [DllImport("Kernel32.dll")]
    extern int FreeConsole();

    [DllImport("Kernel32.dll")]
    extern int AttachConsole(UInt32 dwProcessId);

...

    // Show a console window
    AllocConsole();
    Console::WriteLine("Write to the console!");

...

    // Hide the console window
    FreeConsole();

Mark Salsbery
Microsoft MVP - Visual C++