C#Winform无标题窗口的拖放实现

private const int WM_NCLBUTTONDOWN = 0xA1;
private const int HTCAPTION = 2;
[DllImport("user32.dll", EntryPoint="SendMessageA")]
private static extern int SendMessage (int hwnd, int wMsg, int wParam, int lParam);
[DllImport("user32.dll")]
private static extern int ReleaseCapture ();
private void Form1_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e)
{
//为当前的应用程序释放鼠标捕获
ReleaseCapture();
//发送消息，让系统误以为你在标题拦上按下鼠标
SendMessage((int)this.Handle,WM_NCLBUTTONDOWN,HTCAPTION,0);
}