窗随鼠动

命名空间
using System.Runtime.InteropServices;

DLL调用

   [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;

窗体的MouseDown事件中写入

ReleaseCapture();
SendMessage(this.Handle, WM_SYSCOMMAND, SC_MOVE + HTCAPTION, 0);