User Define Message

You need total 3 steps to define your message

 

[DllImport("user32.dll")]public static extern IntPtr SendMessage(IntPtr hWnd, int msg, IntPtr wPar, IntPtr lPar);

 

public const int UserMsg = 0x0600;SendMessage(this.Parent.Handle, UserMsg, (IntPtr)1, (IntPtr)1);

 

protected override void WndProc(ref Message m){            switch (m.Msg)            {                case 0x0600:                                                            break;                default:                    base.WndProc(ref m);                    break;            }}