public static void ShowSystemMenu(IntPtr hwnd)
{
if (hwnd == IntPtr.Zero)
{
return;
}
Point defPnt = new Point();
WinAPI.GetCursorPos(ref defPnt);
IntPtr hmenu = WinAPI.GetSystemMenu(hwnd, false);
IntPtr cmd = WinAPI.TrackPopupMenuEx(hmenu, Constants.TPM_LEFTBUTTON | Constants.TPM_RETURNCMD, (uint)defPnt.X, (uint)defPnt.Y, hwnd, IntPtr.Zero);
if (cmd != IntPtr.Zero)
{
WinAPI.PostMessage(hwnd, Constants.WM_SYSCOMMAND, cmd, IntPtr.Zero);
}
}