C#使用API屏蔽系统热键和任务管理器

这里有两个版本的屏蔽程序，都是我在网上找到的，对于这两个程序我做了一些很小的修改。
这里我介绍他们两个的程序只是为了充分的学习。
第一个比较完善，在CSDN上可以下到，是个源代码，可以运行
http://download.csdn.net/source/1050757
源码就不在这里贴了
第二个有一些小问题，不过经过您自己的一定的修改也可以广泛应用。
【转】/content/3584194.html
此程序对于屏蔽键盘的回调函数（钩子）不好用
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_USER\Software\Microsoft\Windows\CurrentVersion\Policies\System] 下的DisableTaskmgr项的值设为"1”来屏蔽任务管理器。