Запрет перемещения за экран

 
private: System::Void Form1_Move(System::Object^  sender, System::EventArgs^  e) 
         {
            for each (Screen^ screen in Screen::AllScreens) {
            short width = screen->Bounds.Width;
            short height = screen->Bounds.Height;
 
             if ((this->Left<10)&(this->Left>-this->Width))
                 this->Left = 10;
             if (this->Left>width-this->Width-10)
                 this->Left = width-this->Width-10;
             if (this->Top > height - this->Height-10)
                 this->Top = height - this->Height-10;
             }
         }

void MessageThread(PVOID pParam)
{
    CString sMSG;
    switch(((UINT *)pParam)[0])
    {
        case WM_SIZE:   sMSG = "WM_SIZE";   break;
        case WM_SIZING: sMSG = "WM_SIZING"; break;
        case WM_MOVE:   sMSG = "WM_MOVE";   break;
        case WM_MOVING: sMSG = "WM_MOVING"; break;
        case WM_SYSCOMMAND:sMSG = "WM_SYSCOMMAND";  break;
    }
    ::MessageBox(NULL, "Íåò - íå ïîëó÷èòñÿ", sMSG, MB_OK);
}
 
LRESULT CCantMoveDlg::WindowProc(UINT message, WPARAM wParam, LPARAM lParam) 
{
    // TODO: Add your specialized code here and/or call the base class
    UINT uMSG = message;
    switch(message)
    {
        case WM_SIZE:
        case WM_SIZING:
        case WM_MOVE:
        case WM_MOVING:
            message = WM_USER;
        case WM_SYSCOMMAND:
            if(wParam == SC_MAXIMIZE )
                wParam = SC_RESTORE;
            if(IsWindowVisible())
            {
                _beginthread(MessageThread, 0, &uMSG);
                Sleep(100);
            }
            break;
    }
    return CDialog::WindowProc(message, wParam, lParam);
}