WINFORM程序如何屏蔽系统热键

//我前两天刚刚做的，屏蔽桌面都可以，不过小心使用啊，
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;

using System.Text;
using System.Diagnostics;
using System.Reflection;
using System.Windows.Forms;
using System.Runtime.InteropServices;

using System.Reflection;
using System.Security.Permissions;
using Microsoft.Win32;

namespace testHook
{
  public partial class Form1 : Form
  {
  //委托  
  public delegate int HookProc(int nCode, int wParam, IntPtr lParam);
  static int hHook = 0;
  public const int WH_KEYBOARD_LL = 13;
  //LowLevel键盘截获，如果是WH_KEYBOARD＝2，并不能对系统键盘截取，Acrobat Reader会在你截取之前获得键盘。  
  HookProc KeyBoardHookProcedure;
  //键盘Hook结构函数  
  [StructLayout(LayoutKind.Sequential)]
  public class KeyBoardHookStruct
  {
  public int vkCode;
  public int scanCode;
  public int flags;
  public int time;
  public int dwExtraInfo;
  }
  #region DllImport
  //设置钩子  
  [DllImport("user32.dll")]
  public static extern int SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hInstance, int threadId);
  [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
  //抽掉钩子  
  public static extern bool UnhookWindowsHookEx(int idHook);
  [DllImport("user32.dll")]
  //调用下一个钩子  
  public static extern int CallNextHookEx(int idHook, int nCode, int wParam, IntPtr lParam);

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

  [DllImport("kernel32.dll")]
  public static extern IntPtr GetModuleHandle(string name);

  [DllImport("User32.dll")]
  public static extern IntPtr FindWindowEx(IntPtr ph, IntPtr ch, String cn, String wn);
  [DllImport("User32.dll")]
  public static extern bool ShowWindow(IntPtr hWnd, long nCmdShow);

  private const uint spi_screensaverrunning = 97;
  [DllImport("user32.dll", CharSet = CharSet.Auto)]
  private static extern bool SystemParametersInfo(uint uiAction, uint uiParam, ref bool pvParam, uint fWinIni);

  #endregion

  #region 自定义事件
  public void HookStart()
  {
  // 安装键盘钩子  
  if (hHook == 0)
  {
  KeyBoardHookProcedure = new HookProc(KeyBoardHookProc);
  hHook = SetWindowsHookEx(WH_KEYBOARD_LL, KeyBoardHookProcedure,
  GetModuleHandle(Process.GetCurrentProcess().MainModule.ModuleName), 0);

  //如果设置钩子失败.  
  if (hHook == 0)
  {
  HookClear();
  //throw new Exception("set Hook failed!");  
  }
  }
  }

  //取消钩子事件  
  public void HookClear()
  {
  bool retKeyboard = true;
  if (hHook != 0)
  {
  retKeyboard = UnhookWindowsHookEx(hHook);
  hHook = 0;
  }
  //如果去掉钩子失败.  
  if (!retKeyboard) throw new Exception("UnhookWindowsHookEx failed.");
  }

  //这里可以添加自己想要的信息处理  
  public static int KeyBoardHookProc(int nCode, int wParam, IntPtr lParam)
  {
  if (nCode >= 0)
  {
  KeyBoardHookStruct kbh = (KeyBoardHookStruct)Marshal.PtrToStructure(lParam, typeof(KeyBoardHookStruct));
  if (kbh.vkCode == (int)Keys.S && (int)Control.ModifierKeys == (int)Keys.Control) // 截获Ctrl+S
  {
  return 1;
  }
  if (kbh.vkCode == (int)Keys.Y && (int)Control.ModifierKeys == (int)Keys.Control + (int)Keys.Alt) //截获Ctrl+Alt+Y  
  {
  return 1;
  }
  if (kbh.vkCode == (int)Keys.LWin) //截获win
  {
  return 1;
  }
  if (kbh.vkCode == (int)Keys.Tab && (int)Control.ModifierKeys == (int)Keys.Alt) //截获Ctrl+Tab
  {
  return 1;
  }
  if (kbh.vkCode == (int)Keys.F4 && (int)Control.ModifierKeys == (int)Keys.Alt)//截获Alt + F4
  {
  return 1;
  }

  if (kbh.vkCode == (int)Keys.E && (int)Control.ModifierKeys == (int)Keys.LWin)//截获win + e
  {
  return 1;
  }

  if (kbh.vkCode == (int)Keys.Escape && (int)Control.ModifierKeys == (int)Keys.Alt)////截获Alt + esc
  {
  return 1;
  }

  if ((int)Control.ModifierKeys == (int)Keys.Control + (int)Keys.Alt + (int)Keys.Delete)//截获Ctrl+Alt+Delete 不成功 , 系统不返回键盘值
  {
  return 1;
  }
  if (kbh.vkCode == (int)Keys.Escape && (int)Control.ModifierKeys == (int)Keys.Control)////截获Ctrl + esc
  {
  return 1;
  }
  }
  return CallNextHookEx(hHook, nCode, wParam, lParam);
  }
  #endregion  

  public void SetCtrlAltDeleteStatus(int value)
  {
  //1不可用 0可用

  Microsoft.Win32.RegistryKey key = Microsoft.Win32.Registry.CurrentUser;
  Microsoft.Win32.RegistryKey keySystem = key.CreateSubKey("Software\\Microsoft\\Windows\\CurrentVersion\\Policies\\System");
  keySystem.SetValue("DisableTaskMgr", 1, Microsoft.Win32.RegistryValueKind.DWord);

  RegistryKey regKey;
  regKey = Registry.CurrentUser.OpenSubKey("Software\\Microsoft\\Windows\\CurrentVersion\\Policies\\System", true);
  if (regKey == null)
  {
  regKey = Registry.CurrentUser.CreateSubKey("Software\\Microsoft\\Windows\\CurrentVersion\\Policies\\System");
  }
  regKey.SetValue("DisableTaskMgr", value, RegistryValueKind.DWord);
  }
  private void DisableAll()
  {
  HookStart();
  IntPtr handleTaskMask = FindWindowEx(IntPtr.Zero, IntPtr.Zero, "Shell_TrayWnd", null);
  ShowWindow(handleTaskMask, 0);
  IntPtr handleDeskTop = FindWindowEx(IntPtr.Zero, IntPtr.Zero, "Progman", null);
  ShowWindow(handleDeskTop, 0);
  SetCtrlAltDeleteStatus(1);
  bool p = true;
  SystemParametersInfo(spi_screensaverrunning, 1, ref p, 0);
  }

  private void RecoverAll()
  {
  HookClear();
  IntPtr handle = FindWindowEx(IntPtr.Zero, IntPtr.Zero, "Shell_TrayWnd", null);
  ShowWindow(handle, 1);
  IntPtr handleDeskTop = FindWindowEx(IntPtr.Zero, IntPtr.Zero, "Progman", null);
  ShowWindow(handleDeskTop, 1);
  SetCtrlAltDeleteStatus(0);
  bool p = true;
  SystemParametersInfo(spi_screensaverrunning, 0, ref p, 0);
  }
  public Form1()
  {
  string xx = Environment.CurrentDirectory;
  InitializeComponent();
  DisableAll();
  }

  private void Form1_Load(object sender, EventArgs e)
  {
  // statrhook();
  }

   

  private void Form1_FormClosing(object sender, FormClosingEventArgs e)
  {
  RecoverAll();
  //sotphook();
  }
  }
}