最近做的一个winform类型的项目中需要屏蔽系统热键，在网上搜索了一下，基本上都是调用api来进行hook操作，下面的代码就可以完成功能
using System;using System.IO;using System.Reflection;using System.Runtime.InteropServices;using System.Windows.Forms;namespace WAT.PMS{
/// <summary> /// Description: Hook Helper类，可以屏蔽一些热键并屏蔽任务管理器 /// Author: ZhangRongHua /// Create DateTime: 2009-6-19 20:21 /// UpdateHistory:
/// </summary> public class HookHelper { #region Delegates public delegate int HookProc(int nCode, Int32 wParam, IntPtr lParam); #endregion #region 变量声明 private HookProc KeyboardHookProcedure; private FileStream MyFs; // 用流来屏蔽ctrl alt delete private const byte LLKHF_ALTDOWN = 0x20; private const byte VK_CAPITAL = 0x14; private const byte VK_ESCAPE = 0x1B; private const byte VK_F4 = 0x73; private const byte VK_LCONTROL = 0xA2; private const byte VK_NUMLOCK = 0x90; private const byte VK_RCONTROL = 0xA3; private const byte VK_SHIFT = 0x10; private const byte VK_TAB = 0x09; public const int WH_KEYBOARD = 13; private const int WH_KEYBOARD_LL = 13; private const int WH_MOUSE = 7; private const int WH_MOUSE_LL = 14; private const int WM_KEYDOWN = 0x100; private const int WM_KEYUP = 0x101; private const int WM_LBUTTONDBLCLK = 0x203; private const int WM_LBUTTONDOWN = 0x201; private const int WM_LBUTTONUP = 0x202; private const int WM_MBUTTONDBLCLK = 0x209; private const int WM_MBUTTONDOWN = 0x207; private const int WM_MBUTTONUP = 0x208; private const int WM_MOUSEMOVE = 0x200; private const int WM_MOUSEWHEEL = 0x020A; private const int WM_RBUTTONDBLCLK = 0x206; private const int WM_RBUTTONDOWN = 0x204; private const int WM_RBUTTONUP = 0x205; private const int WM_SYSKEYDOWN = 0x104; private const int WM_SYSKEYUP = 0x105; private static int hKeyboardHook = 0; #endregion #region 函数转换 [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)] public static extern int SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hInstance, int threadId); // 卸载钩子 [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)] public static extern bool UnhookWindowsHookEx(int idHook); // 继续下一个钩子 [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)] public static extern int CallNextHookEx(int idHook, int nCode, Int32 wParam, IntPtr lParam); // 取得当前线程编号 [DllImport("kernel32.dll")] private static extern int GetCurrentThreadId(); [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)] private static extern short GetKeyState(int vKey); #endregion #region 方法 /// <summary> /// 钩子回调函数，在这里屏蔽热键。 /// <remark> /// Author:ZhangRongHua /// Create DateTime: 2009-6-19 20:19 /// Update History: /// </remark> /// </summary> /// <param name="nCode">The n code.</param> /// <param name="wParam">The w param.</param> /// <param name="lParam">The l param.</param> /// <returns></returns> private int KeyboardHookProc(int nCode, Int32 wParam, IntPtr lParam) { KeyMSG m = (KeyMSG) Marshal.PtrToStructure(lParam, typeof (KeyMSG)); if (((Keys) m.vkCode == Keys.LWin) || ((Keys) m.vkCode == Keys.RWin) || ((m.vkCode == VK_TAB) && ((m.flags & LLKHF_ALTDOWN) != 0)) || ((m.vkCode == VK_ESCAPE) && ((m.flags & LLKHF_ALTDOWN) != 0)) || ((m.vkCode == VK_F4) && ((m.flags & LLKHF_ALTDOWN) != 0)) || (m.vkCode == VK_ESCAPE) && ((GetKeyState(VK_LCONTROL) & 0x8000) != 0) || (m.vkCode == VK_ESCAPE) && ((GetKeyState(VK_RCONTROL) & 0x8000) != 0) ) { return 1; } return CallNextHookEx(hKeyboardHook, nCode, wParam, lParam); } /// <summary> /// 启动Hook，并用流屏蔽任务管理器 /// <remark> /// Author:ZhangRongHua /// Create DateTime: 2009-6-19 20:20 /// Update History: /// </remark> /// </summary> public void HookStart() { if (hKeyboardHook == 0) { // 创建HookProc实例 KeyboardHookProcedure = new HookProc(KeyboardHookProc); hKeyboardHook = SetWindowsHookEx(WH_KEYBOARD, KeyboardHookProcedure, Marshal.GetHINSTANCE(Assembly.GetExecutingAssembly().GetModules()[0]), 0); // 如果设置钩子失败 if (hKeyboardHook == 0) { HookStop(); //throw new Exception("SetWindowsHookEx failedeeeeeeee."); } //用二进制流的方法打开任务管理器。而且不关闭流.这样任务管理器就打开不了 MyFs = new FileStream(Environment.ExpandEnvironmentVariables("%windir%\system32\taskmgr.exe"), FileMode.Open); byte[] MyByte = new byte[(int) MyFs.Length]; MyFs.Write(MyByte, 0, (int) MyFs.Length); } } /// <summary> /// 卸载hook,并关闭流，取消屏蔽任务管理器。 /// <remark> /// Author:ZhangRongHua /// Create DateTime: 2009-6-19 20:21 /// Update History: /// </remark> /// </summary> public void HookStop() { bool retKeyboard = true; if (hKeyboardHook != 0) { retKeyboard = UnhookWindowsHookEx(hKeyboardHook); hKeyboardHook = 0; } if (null != MyFs) { MyFs.Close(); } if (!(retKeyboard)) { throw new Exception("UnhookWindowsHookEx failedsssss."); } } #endregion #region Nested type: KeyMSG public struct KeyMSG { public int dwExtraInfo; public int flags; public int scanCode; public int time; public int vkCode; } #endregion }
}PS：也可以通过将[HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionPoliciesSystem] 下的DisableTaskmgr项的值设为"1”来屏蔽任务管理器。
也可以参考：如何使用注册表禁用任务管理器 http://jingyan.baidu.com/article/1e5468f91d8813484861b769.html 百度经验
参考：http://www.cnblogs.com/zhangronghua/archive/2009/06/19/1507031.html