C# winform无边框窗体移动

    public partial class MessageHints : Form

    {

        //窗体移动API

        [DllImport("user32.dll")]

        public static extern bool ReleaseCapture();

        [DllImport("user32.dll")]

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

        public const int WM_SYSCOMMAND = 0x0112;

        public const int SC_MOVE = 0xF010;

        public const int HTCAPTION = 0x0002;

        [DllImport("user32")]

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

        private const int WM_SETREDRAW = 0xB;

        public MessageHints()

        {

            InitializeComponent();

        }

1.窗体的最上面加上这一部分

 private void labelX1_MouseDown(object sender, MouseEventArgs e)

        {

            if (this.WindowState == FormWindowState.Normal)

            {

                ReleaseCapture();

                SendMessage(this.Handle, WM_SYSCOMMAND, SC_MOVE + HTCAPTION, );

            }

        }

2.事件中调取