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用钩子取得按键信息实例

发布时间: 2012-11-23 00:03:43 作者: rapoo

用钩子获得按键信息实例

实例:实现获得按键信息

窗体相关代码:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using System.Threading;
using ReadBadCode;

namespace gouzi
{
public partial class Form2 : Form
{
BarCodeHook BarCode = new BarCodeHook();
public Form2()
{
InitializeComponent();
BarCode.BarCodeEvent += new BarCodeHook.BarCodeDelegate(BarCode_BarCodeEvent);

}
private delegate void ShowInfoDelegate(BarCodeHook.BarCodes barCode);
private void ShowInfo(BarCodeHook.BarCodes barCode)
{
if (this.InvokeRequired)
{
this.BeginInvoke(new ShowInfoDelegate(ShowInfo), new object[] { barCode });
}
else
{
textBox1.Text = barCode.KeyName;//键名
textBox2.Text = barCode.VirtKey.ToString();//虚拟码
textBox3.Text = barCode.ScanCode.ToString();//扫描码
textBox4.Text = barCode.AscII.ToString();//AscII
textBox5.Text = barCode.Chr.ToString();//字符
textBox6.Text = barCode.IsValid ? barCode.BarCode : "";//在这里进行键入值
}
}
void BarCode_BarCodeEvent(BarCodeHook.BarCodes barCode)
{
ShowInfo(barCode);
}
private void Form2_Load(object sender, EventArgs e)
{
BarCode.Start();

}
private void Form2_StyleChanged(object sender, EventArgs e)
{
BarCode.Stop();

}

}
}

............................................................................................................................................

后台类代码

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Runtime.InteropServices;
using System.Reflection;

namespace ReadBadCode
{
class BarCodeHook
{
public delegate void BarCodeDelegate(BarCodes barCode);
public event BarCodeDelegate BarCodeEvent;

public struct BarCodes
{
public int VirtKey; //虚拟码
public int ScanCode; //扫描码
public string KeyName; //键名
public uint AscII; //AscII
public char Chr; //字符

public string BarCode; //条码信息
public bool IsValid; //条码是否有效
public DateTime Time; //扫描时间
}

private struct EventMsg
{
public int message;
public int paramL;
public int paramH;
public int Time;
public int hwnd;
}
// 安装钩子
[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
private 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)]
private static extern bool UnhookWindowsHookEx(int idHook);

// 继续下一个钩子
[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
private static extern int CallNextHookEx(int idHook, int nCode, Int32 wParam, IntPtr lParam);

//获取键名的字符串
[DllImport("user32", EntryPoint = "GetKeyNameText")]
private static extern int GetKeyNameText(int lParam, StringBuilder lpBuffer, int nSize);

//将256个虚拟键复制到指定的缓冲区中
[DllImport("user32", EntryPoint = "GetKeyboardState")]
private static extern int GetKeyboardState(byte[] pbKeyState);

//将指定的虚拟键码和键盘状态为相应的字符串
[DllImport("user32", EntryPoint = "ToAscii")]
private static extern bool ToAscii(int VirtualKey, int ScanCode, byte[] lpKeyState, ref uint lpChar, int uFlags);

//声明定义回调函数
delegate int HookProc(int nCode, Int32 wParam, IntPtr lParam);
BarCodes barCode = new BarCodes();
int hKeyboardHook = 0;
string strBarCode = "";

private int KeyboardHookProc(int nCode, Int32 wParam, IntPtr lParam)
{
if (nCode == 0)
{
EventMsg msg = (EventMsg)Marshal.PtrToStructure(lParam, typeof(EventMsg));

if (wParam == 0x100) //WM_KEYDOWN = 0x100
{
barCode.VirtKey = msg.message & 0xff; //虚拟码
barCode.ScanCode = msg.paramL & 0xff; //扫描码

StringBuilder strKeyName = new StringBuilder(255);
if (GetKeyNameText(barCode.ScanCode * 65536, strKeyName, 255) > 0)
{
barCode.KeyName = strKeyName.ToString().Trim(new char[] { ' ', '\0' });
}
else
{
barCode.KeyName = "";
}

byte[] kbArray = new byte[256];
uint uKey = 0;
GetKeyboardState(kbArray);
if (ToAscii(barCode.VirtKey, barCode.ScanCode, kbArray, ref uKey, 0))
{
barCode.AscII = uKey;
barCode.Chr = Convert.ToChar(uKey);
}

if (DateTime.Now.Subtract(barCode.Time).TotalMilliseconds > 50)
{
strBarCode = barCode.Chr.ToString();
}
else
{
if ((msg.message & 0xff) == 13 && strBarCode.Length > 3) //回车
{
barCode.BarCode = strBarCode;
barCode.IsValid = true;
}
strBarCode += barCode.Chr.ToString();
}

barCode.Time = DateTime.Now;
if (BarCodeEvent != null) BarCodeEvent(barCode); //触发事件
barCode.IsValid = false;
}
}
return CallNextHookEx(hKeyboardHook, nCode, wParam, lParam);
}

// 安装钩子
public bool Start()
{
if (hKeyboardHook == 0)
{
//WH_KEYBOARD_LL = 13
hKeyboardHook = SetWindowsHookEx(13, new HookProc(KeyboardHookProc), Marshal.GetHINSTANCE(Assembly.GetExecutingAssembly().GetModules()[0]), 0);
}
return (hKeyboardHook != 0);
}

// 卸载钩子
public bool Stop()
{
if (hKeyboardHook != 0)
{
return UnhookWindowsHookEx(hKeyboardHook);
}
return true;
}

}
}

【注意】要想测试实际的效果,必须执行编译后的Exe文件,在开发环境直接运行会没有效果的。

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