c# 屏蔽快捷鍵的實現(xiàn)示例

更新時間：2021年03月11日 09:35:53 作者：leestar54

這篇文章主要介紹了c# 屏蔽快捷鍵的實現(xiàn)示例，幫助大家更好的理解和利用c#進(jìn)行桌面開發(fā)，感興趣的朋友可以了解下

前言

有時候開發(fā)會遇到這樣一個需求，軟件需要屏蔽用戶的組合快捷鍵或某些按鍵，避免強(qiáng)制退出軟件，防止勿操作等。

原理

1、要實現(xiàn)組合鍵，按鍵攔截，需要用到user32.dll中的SetWindowsHookEx。

2、要攔截ctrl+alt+del，需要使用ntdll.dll的ZwSuspendProcess函數(shù)掛起winlogon程序，退出之后使用ZwResumeProcess恢復(fù)winlogon程序。

3、軟件需要開啟topMost，以及全屏，否則離開軟件則攔截?zé)o效。

4、如果要實現(xiàn)熱鍵監(jiān)聽（非焦點攔截），則需要用到user32.dll的RegisterHotKey以及UnregisterHotKey。

實現(xiàn)

1、Program類

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Windows.Forms;

namespace LockForm
{
 static class Program
 {
  /// <summary>
  /// 應(yīng)用程序的主入口點。
  /// </summary>
  [STAThread]
  static void Main()
  {
   Application.EnableVisualStyles();
   Application.SetCompatibleTextRenderingDefault(false);
   SuspendWinLogon();
   Application.Run(new Form1());
   ResumeWinLogon();
  }

  [DllImport("ntdll.dll")]
  public static extern int ZwSuspendProcess(IntPtr ProcessId);
  [DllImport("ntdll.dll")]
  public static extern int ZwResumeProcess(IntPtr ProcessId);

  private static void SuspendWinLogon()
  {
   Process[] pc = Process.GetProcessesByName("winlogon");
   if (pc.Length > 0)
   {
    ZwSuspendProcess(pc[0].Handle);
   }
  }

  private static void ResumeWinLogon()
  {
   Process[] pc = Process.GetProcessesByName("winlogon");
   if (pc.Length > 0)
   {
    ZwResumeProcess(pc[0].Handle);
   }
  }
 }
}

2、Form1類

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Drawing;
using System.Runtime.InteropServices;
using System.Text;
using System.Windows.Forms;

namespace LockForm
{
 public partial class Form1 : Form
 {
  public Form1()
  {
   InitializeComponent();
  }

  private void button1_Click(object sender, EventArgs e)
  {
   if (textBox1.Text == "123")
   {
    Application.ExitThread();
   }
   else
   {
    webBrowser1.Navigate(textBox1.Text);
   }
  }

  private void Form1_Load(object sender, EventArgs e)
  {
   //webBrowser1.Navigate("https://baidu.com");
   HookStart();
   //this.TopMost = false;
   //SuspendWinLogon();
  }

  private void webBrowser1_NewWindow(object sender, CancelEventArgs e)
  {
   e.Cancel = true;
   webBrowser1.Navigate(webBrowser1.Document.ActiveElement.GetAttribute("href"));
  }

  private void button3_Click(object sender, EventArgs e)
  {
   webBrowser1.GoBack();
  }

  private void button2_Click(object sender, EventArgs e)
  {
   webBrowser1.GoForward();
  }

  private void button4_Click(object sender, EventArgs e)
  {
   webBrowser1.GoHome();
  }

  private void webBrowser1_Navigated(object sender, WebBrowserNavigatedEventArgs e)
  {
   textBox1.Text = webBrowser1.Url.ToString();
  }

  private void webBrowser1_Navigating(object sender, WebBrowserNavigatingEventArgs e)
  {

  }

  #region 鍵盤鉤子

  public delegate int HookProc(int nCode, int wParam, IntPtr lParam);//定義全局鉤子過程委托，以防被回收（鉤子函數(shù)原型）
  HookProc KeyBoardProcedure;

  //定義鍵盤鉤子的相關(guān)內(nèi)容，用于截獲鍵盤消息
  static int hHook = 0;//鉤子函數(shù)的句柄
  public const int WH_KEYBOARD = 13;
  //鉤子結(jié)構(gòu)函數(shù)
  public struct KeyBoardHookStruct
  {
   public int vkCode;
   public int scanCode;
   public int flags;
   public int time;
   public int dwExtraInfo;

  }
  //安裝鍵盤鉤子
  public void HookStart()
  {

   if (hHook == 0)
   {
    //實例化一個HookProc對象
    KeyBoardProcedure = new HookProc(Form1.KeyBoardHookProc);

    //創(chuàng)建線程鉤子
    hHook = Win32API.SetWindowsHookEx(WH_KEYBOARD, KeyBoardProcedure, Win32API.GetModuleHandle(Process.GetCurrentProcess().MainModule.ModuleName), 0);

    //如果設(shè)置線程鉤子失敗
    if (hHook == 0)
    {
     HookClear();
    }
   }
  }

  //取消鉤子
  public void HookClear()
  {
   bool rsetKeyboard = true;
   if (hHook != 0)
   {
    rsetKeyboard = Win32API.UnhookWindowsHookEx(hHook);
    hHook = 0;
   }
   if (!rsetKeyboard)
   {
    throw new Exception("取消鉤子失敗!");
   }
  }
  //對截獲的鍵盤操作的處理
  public static int KeyBoardHookProc(int nCode, int wParam, IntPtr lParam)
  {
   if (nCode >= 0)
   {
    KeyBoardHookStruct kbh = (KeyBoardHookStruct)Marshal.PtrToStructure(lParam, typeof(KeyBoardHookStruct));

    if (kbh.vkCode == 91)//截獲左邊WIN鍵
    {
     return 1;
    }
    if (kbh.vkCode == 92)//截獲右邊WIN鍵
    {
     return 1;
    }
    if (kbh.vkCode == (int)Keys.Escape && (int)Control.ModifierKeys == (int)Keys.Control)//截獲Ctrl+ESC鍵
    {
     return 1;
    }
    if (kbh.vkCode == (int)Keys.Escape && (int)Control.ModifierKeys == (int)Keys.Alt)
    {
     return 1;
    }
    if (kbh.vkCode == (int)Keys.F4 && (int)Control.ModifierKeys == (int)Keys.Alt)//截獲ALT+F4
    {
     return 1;
    }
    if (kbh.vkCode == (int)Keys.Tab && (int)Control.ModifierKeys == (int)Keys.Alt)//截獲ALT+TAB
    {
     return 1;
    }
    if (kbh.vkCode == (int)Keys.Delete&&(int)Control.ModifierKeys == (int)Keys.Control + (int)Keys.Alt)
    {
     return 1;
    }
    if ( kbh.vkCode == (int) Keys.Escape && (int) Control.ModifierKeys == (int) Keys.Control + (int) Keys.Alt ) /* 截獲Ctrl+Shift+Esc */
    {
     return 1;
    }

   }

   return Win32API.CallNextHookEx(hHook, nCode, wParam, lParam);
  }
  #endregion
 }
}

3、聲明windows api

//設(shè)置鉤子
  [DllImport("user32.dll")]
  public static extern int SetWindowsHookEx(int idHook, LockForm.Form1.HookProc lpfn, IntPtr hInstance, int threadID);

  //卸載鉤子
  [DllImport("user32.dll", CallingConvention = CallingConvention.StdCall)]
  public static extern bool UnhookWindowsHookEx(int idHook);

  //調(diào)用下一個鉤子
  [DllImport("user32.dll")]
  public static extern int CallNextHookEx(int idHook, int nCode, int wParam, IntPtr lParam);