calling C# method (Delegate) from Win32 DLL
We try callback C# method from C++ DLL using delegate, using delegate without argument works fine for me however the CallBackFunctionWithParameter which call delegate with parameter crash the application after being called .
Any suggestion will help and really appreaciated
Thanks
Budi
Here is the code :
In C#
=======================================================================
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.Runtime.InteropServices;
namespace FunctionCallbacks
{
public class Form1 : System.Windows.Forms.Form
{
delegate void delegateMethod ();
delegate void delegateMethodWithParameter(int i);
private System.Windows.Forms.Button button1;
///
/// Required designer variable.
///
private System.ComponentModel.Container components = null;
[DllImport("..\\..\\..\\C++\\Debug\\C++.dll")]
private static extern void CallBackFunction (delegateMethod method);
[DllImport("..\\..\\..\\C++\\Debug\\C++.dll")]
private static extern void CallBackFunctionWithParameter (delegateMethodWithParameter method);
public Form1()
{
//
// Required for Windows Form Designer support
//
InitializeComponent();
}
///
/// Clean up any resources being used.
///
protected override void Dispose( bool disposing )
{
if( disposing )
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}
#region Windows Form Designer generated code
///
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
///
private void InitializeComponent()
{
this.button1 = new System.Windows.Forms.Button();
this.SuspendLayout();
//
// button1
//
this.button1.Location = new System.Drawing.Point(88, 120);
this.button1.Name = "button1";
this.button1.TabIndex = 0;
this.button1.Text = "button1";
this.button1.Click += new System.EventHandler(this.button1_Click);
//
// Form1
//
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(292, 266);
this.Controls.Add(this.button1);
this.Name = "Form1";
this.Text = "Form1";
this.Load += new System.EventHandler(this.Form1_Load);
this.ResumeLayout(false);
}
#endregion
///
/// The main entry point for the application.
///
[STAThread]
static void Main()
{
Application.Run(new Form1());
}
private void Form1_Load(object sender, System.EventArgs e)
{
}
private void button1_Click(object sender, System.EventArgs e)
{
delegateMethod d = new delegateMethod(PrintMessage);
delegateMethodWithParameter f = new delegateMethodWithParameter(PrintMessageWithParameter);
CallBackFunction (d); //in C++ dll
CallBackFunctionWithParameter(f); //in C++ dll
}
public void PrintMessage ( )
{
MessageBox.Show ("Hello");
}
public void PrintMessageWithParameter(int i)
{
MessageBox.Show(i.ToString());
}
}
}
=======================================================================
In Win32 DLL
=======================================================================.
.
.
//takes a function pointer as an argument
extern "C" __declspec(dllexport) void CallBackFunction (void(*callFunction()))
{
callFunction (); //call 'PrintMessage()' method in C#
}
//takes a function pointer as an argument
extern "C" __declspec(dllexport) void CallBackFunctionWithParameter (void (*callFunctionWithParameter) (int i))
{
callFunctionWithParameter(111); // call 'PrintMessage()' method // in C#
}
.
.
.