键盘钩子实例

键盘钩子实例一、界面样式如下：主要功能如下：安装钩子拦截按键，允许按键有效和无效，可以记录按键，以及取消钩子。

二、定义界面控件：label1 标记按键、button1 安装钩子按钮、button2 取消钩子按钮三、源码1、主界面Form1using System.Data;using System.Drawing;using System.Text;using System.Windows.Forms;using System.Runtime.InteropServices;using System.Reflection;using System.Diagnostics;using Microsoft.Win32;using WinformHook;namespace WinformHook{public partial class Form1 : Form{//钩子管理对象private KeyboardHookLib _keyboardHook = null;public Form1(){InitializeComponent();}private void button1_Click(object sender, EventArgs e){//安装钩子_keyboardHook = new KeyboardHookLib();_keyboardHook.InstallHook(this.OnKeyPress);}private void button2_Click(object sender, EventArgs e){//取消钩子if (_keyboardHook != null) _keyboardHook.UninstallHook();}///<summary>///客户端键盘捕捉事件///</summary>///<param name="hookStruct">由Hook程序发送的按键信息</param>///<param name="handle">是否拦截</param>public void OnKeyPress(KeyboardHookLib.HookStruct hookStruct, out bool handle){handle = false; //预设置不拦截任何键if (hookStruct.vkCode == 91) //截获左侧开始win键{handle = true;}if (hookStruct.vkCode == 92)// 截获右侧开始win键{handle = true;}//截获Ctrl+Escif (hookStruct.vkCode == (int)Keys.Escape && (int)Control.ModifierKeys ==(int)Keys.Control){handle = true;}//截获alt+f4if (hookStruct.vkCode == (int)Keys.F4 && (int)Control.ModifierKeys == (int)Keys.Alt){handle = true;}//截获alt+tabif (hookStruct.vkCode == (int)Keys.Tab && (int)Control.ModifierKeys == (int)Keys.Alt){handle = true;}//截获F1if (hookStruct.vkCode == (int)Keys.F1){handle = true;}//截获Ctrl+Alt+Deleteif ((int)Control.ModifierKeys == (int)Keys.Control + (int)Keys.Alt + (int)Keys.Delete){handle = true;}//如果键A~Zif (hookStruct.vkCode >= (int)Keys.A && hookStruct.vkCode <= (int)Keys.Z){//挡掉B键if (hookStruct.vkCode == (int)Keys.B)hookStruct.vkCode = (int)Keys.None; //设键为0handle = true;}Keys key = (Keys)hookStruct.vkCode;label1.Text = "你按下:" + (key == Keys.None ? "" : key.ToString());}}}2、键盘钩子操作类KeyboardHookLibusing System;using System.Collections.Generic;using System.Text;using System.Runtime.InteropServices;using System.Reflection;using System.Diagnostics;using Microsoft.Win32;using System.Windows.Forms;namespace WinformHook{///<summary>///键盘Hook管理类///</summary>public class KeyboardHookLib{private const int WH_KEYBOARD_LL = 13; //键盘//键盘处理事件委托,当捕获键盘输入时调用定义该委托的方法private delegate int HookHandle(int nCode, int wParam, IntPtr lParam);//客户端键盘处理事件public delegate void ProcessKeyHandle(HookStruct param, out bool handle);//接收SetWindowsHookEx返回值private static int _hHookValue = 0;//勾子程序处理事件private HookHandle _KeyBoardHookProcedure;//Hook结构[StructLayout(LayoutKind.Sequential)]public class HookStruct{public int vkCode;public int scanCode;public int flags;public int time;public int dwExtraInfo;}//设置钩子[DllImport("user32.dll")]private static extern int SetWindowsHookEx(int idHook, HookHandle lpfn, IntPtr hInstance, int threadId);//取消钩子[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]private static extern bool UnhookWindowsHookEx(int idHook);//调用下一个钩子[DllImport("user32.dll")]private static extern int CallNextHookEx(int idHook, int nCode, int wParam, IntPtr lParam);//获取当前线程[DllImport("kernel32.dll")]private static extern int GetCurrentThreadId();//Gets the main module for the associated process.[DllImport("kernel32.dll")]private static extern IntPtr GetModuleHandle(string name);private IntPtr _hookWindowPtr = IntPtr.Zero;//构造器public KeyboardHookLib() { }//外部调用的键盘处理事件private static ProcessKeyHandle _clientMethod = null;///<summary>///安装勾子///</summary>///<param name="hookProcess">外部调用的键盘处理事件</param>public void InstallHook(ProcessKeyHandle clientMethod){_clientMethod = clientMethod;// 安装键盘钩子if (_hHookValue == 0){_KeyBoardHookProcedure = new HookHandle(OnHookProc);_hookWindowPtr =GetModuleHandle(Process.GetCurrentProcess().MainModule.ModuleName);_hHookValue = SetWindowsHookEx(WH_KEYBOARD_LL,_KeyBoardHookProcedure,_hookWindowPtr,0);//如果设置钩子失败if (_hHookValue == 0) UninstallHook();}}//取消钩子事件public void UninstallHook(){if (_hHookValue != 0){bool ret = UnhookWindowsHookEx(_hHookValue);if (ret) _hHookValue = 0;}}//钩子事件内部调用调用方法转发到端应用private static int OnHookProc(int nCode, int wParam, IntPtr lParam){if (nCode >= 0){//转换结构HookStruct hookStruct = (HookStruct)Marshal.PtrToStructure(lParam, typeof(HookStruct));if (_clientMethod != null){bool handle = false;//调用客户提供的事件处理程序_clientMethod(hookStruct, out handle);if (handle) return 1; //表示拦截键盘退出}}return CallNextHookEx(_hHookValue, nCode, wParam, lParam);}}}。