c#中通过设置钩子监视鼠标移动

这个问题来自论坛提问，C#的大致代码如下

using  System;
using  System.Windows.Forms;
using  System.Runtime.InteropServices;
namespace  WindowsApplication1
... {
     public   partial   class  Form1 : Form
     ... {
         public  Form1()
         ... {
            InitializeComponent();
        }
         
         private   void  Form1_Load( object  sender, EventArgs e)
         ... {
            Win32Hook hook  =   new  Win32Hook();
            hook.onMouseChange  +=   new  EventHandler(hook_onMouseChange);
            hook.SetHook();
        }

         void  hook_onMouseChange( object  sender, EventArgs e)
         ... {
             this .Text  =  Cursor.Position.ToString();
        }
    }
     public   class  Win32Hook
     ... {

        [DllImport( " kernel32 " )]
         public   static   extern   int  GetCurrentThreadId();

        [DllImport( " user32 " ,CharSet  =  CharSet.Auto, CallingConvention  =  CallingConvention.StdCall)]
         public   static   extern   int  SetWindowsHookEx(
            HookType idHook,
            HOOKPROC lpfn,
             int  hmod,
             int  dwThreadId);

         public   enum  HookType
         ... {
            WH_GETMESSAGE  =   3
        }

         public   delegate   int  HOOKPROC( int  nCode,  int  wParam,  int  lParam);

         public   event  System.EventHandler onMouseChange;

         public   void  SetHook()
         ... {
            SetWindowsHookEx(HookType.WH_GETMESSAGE,
                 new  HOOKPROC( this .MyKeyboardProc),
                 0 ,
                GetCurrentThreadId());
        }

         public   int  MyKeyboardProc( int  nCode,  int  wParam,  int  lParam)
         ... {
             if  (onMouseChange  !=   null )
             ... {
                onMouseChange( null ,  null );
            }
             return   0 ;
        }
    }
}