C# 无边框窗体移动

[System.Runtime.InteropServices.DllImport("user32.dll")]
private static extern IntPtr SendMessage(IntPtr hWnd, int msg, int wparam, int lparam);
protected override void OnMouseDown(MouseEventArgs e)
{
base.OnMouseDown(e);
if (e.Button == MouseButtons.Left)//按下的是鼠标左键
{
Capture = false;//释放鼠标，使能够手动操作
SendMessage(this.Handle, 0x00A1, 2, 0);//拖动窗体
}
}