1         using System.Runtime.InteropServices;  
 2         //并为控件 添加 MouseDown 事件 
 3 
 4         // C#鼠标拖动任意控件 
 5 
 6         // 利用Windows的API函数：SendMessage 和 ReleaseCapture 
 7         const uint WM_SYSCOMMAND = 0x0112;
 8         const uint SC_MOVE = 0xF010;
 9         const uint HTCAPTION = 0x0002;
10 
11         [DllImport("user32.dll", EntryPoint = "SendMessageA")]
12         private static extern int SendMessage(IntPtr hwnd, uint wMsg, uint wParam, uint lParam);
13         [DllImport("user32.dll")]
14         private static extern int ReleaseCapture();
15 
16         void ControlMouseDown(object sender, MouseEventArgs e)
17         {
18             ReleaseCapture();
19             SendMessage((sender as Control).Handle, WM_SYSCOMMAND, SC_MOVE + HTCAPTION, 0);
20         }