.Net不能做消息钩子(WH_GETMESSAGE)吗?

public class MyHook

{

	const int WH_GETMESSAGE=3;



	[DllImport("user32.dll")]

	public static extern IntPtr SetWindowsHookEx(int hookType,HookProc hookProc,IntPtr instance,int threadID);

	[DllImport("user32.dll")]

	public static extern IntPtr CallNextHookEx(IntPtr hookHandle, int nCode, IntPtr wParam, IntPtr lParam);



	public delegate IntPtr HookProc(int nCode, IntPtr wParam, IntPtr lParam);



	static IntPtr hookHandle=IntPtr.Zero;//钩子的句柄



	/// <summary>

	/// 安装钩子

	/// </summary>

	/// <returns></returns>

	public static bool SetHook()

	{

		IntPtr h=Marshal.GetHINSTANCE(System.Reflection.Assembly.GetExecutingAssembly().GetModules()[0]);

		hookHandle = SetWindowsHookEx(WH_GETMESSAGE,new HookProc(HookCallBack),h,0);

		if(hookHandle==IntPtr.Zero)

		{

			System.Windows.Forms.MessageBox.Show("安装失败了");

			return false;

		}

		return true;

	}





	public static IntPtr HookCallBack(int nCode,IntPtr wParam,IntPtr lParam)

	{

		System.Diagnostics.Debug.WriteLine("有消息近来了");//只会执行一次



		if(nCode < 0)

		{

			CallNextHookEx(hookHandle,nCode,wParam,lParam);

			return IntPtr.Zero;

		}

		else

		{

			return CallNextHookEx(hookHandle,nCode,wParam,lParam);

		}

	}





}