//记得一定导入模块

 using System.Runtime.InteropServices;

/**
* 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;

/**
* 主窗体点击时的事件
*/

private void FrmMaster_MouseDown(object sender, MouseEventArgs e)
{
　　if (this.WindowState == FormWindowState.Normal)
　　{
　　ReleaseCapture();
　　SendMessage(this.Handle, WM_SYSCOMMAND, SC_MOVE + HTCAPTION, 0);
　　}
}

C#-Winform窗体类型为None，设置移动效果