[DllImport("user32.dll")]

        public static extern bool ReleaseCapture();

        [DllImport("user32.dll")]

        public static extern bool SendMessage(IntPtr hwnd, int wMsg, int wParam, int lParam);

        public const int WM_SYSCOMMAND = 0x0112;

        public const int SC_MOVE = 0xF010;

        public const int HTCAPTION = 0x0002;

        private void tab_title_MouseDown(object sender, MouseEventArgs e)

        {

            ReleaseCapture();

            SendMessage(this.Handle, WM_SYSCOMMAND, SC_MOVE + HTCAPTION, );//*********************调用移动无窗体控件函数

        }

        public LargeIcoMainForm()

        {

            InitializeComponent();

            this.tab_title.MouseDown += new System.Windows.Forms.MouseEventHandler(this.tab_title_MouseDown);

        }