本文所述实例为C#结合数据库，来验证所识别的ID卡内容，通过本实例代码，用户可以轻松实现对ID卡会员信息的验证。该实例代码可实现读取数据库，进而逐步实现数据库连接，数据库读取，ID卡读取，ID卡信息与数据库内容比对，最终返回结果并告之是否验证成功。
具体功能代码如下：
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.Data.OleDb;
using System.Runtime.InteropServices;
using System.Diagnostics;
using System.Collections;
namespace IDCard
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
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;
[DllImport("kernel32")]
public static extern int Beep(int dwFreq, int dwDuration);//让计算机蜂鸣
string DataPath = "";//数据库路径
OleDbConnection con;//OleDbConnection对象，连接数据库
OleDbCommand cmd;//OleDbCommand对象，执行SQL语句
//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;
}
[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 IntPtr GetModuleHandle(string name);
public string getNum(string code)
{
string flag = "";
switch (code)
{
case "048":
flag="0"; break;
case "049":
flag = "1"; break;
case "050":
flag = "2"; break;
case "051":
flag = "3"; break;
case "052":
flag = "4"; break;
case "053":
flag = "5"; break;
case "054":
flag = "6"; break;
case "055":
flag = "7"; break;
case "056":
flag = "8"; break;
case "057":
flag = "9"; break;
}
return flag;
}
public void Hook_Start()
{
// 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)
{
Hook_Clear();
}
}
}
//取消钩子事件
public void Hook_Clear()
{
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
string NumCode="";
public int KeyBoardHookProc(int nCode, int wParam, IntPtr lParam)
{
if (nCode >= 0)
{
if (wParam == 0x0104 || wParam == 0x0100)
{
KeyBoardHookStruct kbh = (KeyBoardHookStruct)Marshal.PtrToStructure(lParam, typeof(KeyBoardHookStruct));
int flag = kbh.vkCode;
switch (flag)
{
case 96:
NumCode += "0"; break;
case 97:
NumCode += "1"; break;
case 98:
NumCode += "2"; break;
case 99:
NumCode += "3"; break;
case 100:
NumCode += "4"; break;
case 101:
NumCode += "5"; break;
case 102:
NumCode += "6"; break;
case 103:
NumCode += "7"; break;
case 104:
NumCode += "8"; break;
case 105:
NumCode += "9"; break;
}
if (flag == 13)
{
if (NumCode.Length != 0)
{
string c = "";
string id = "";
for (int i = 0; i 0)//如果大于0则说明已经添加过
{
//弹出警告信息
if (MessageBox.Show("ID卡号已经添加过了！", "警告", MessageBoxButtons.OK, MessageBoxIcon.Error) == DialogResult.OK)
{
button2_Click(sender, e);//清空输入ID卡号和员工姓名的文本框
}
}
else//如果小于0说明没有添加过
{
//实例化OleDbCommand对象
cmd = new OleDbCommand("insert into tb_UserInfo(CardID,UName,USex,UDep) values ('" + txtIdcard.Text.Trim() + "','" + txtName.Text.Trim() + "','" + cbbsex.Text.Trim() + "','" + cbbdep.Text.Trim() + "')", con);
int k = cmd.ExecuteNonQuery();//执行insert语句，将输入的信息添加到数据库中
if (k > 0)//如果大于0则操作成功
{
//弹出提示信息
if (MessageBox.Show("添加成功！", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information) == DialogResult.OK)
{
button2_Click(sender, e);//清空输入ID卡号和员工姓名的文本框
}
}
}
con.Close();//关闭数据库连接
}
}
}
private void txtIdcard_KeyPress(object sender, KeyPressEventArgs e)
{
if (!(e.KeyChar = '0') && e.KeyChar != 'r' && e.KeyChar != 'b')
{
e.Handled = true;
}
}
}
}
该实例注释完善，便于阅读，读者还可以根据自身需求改善代码，或者添加新的功能以满足自身应用的个性化需求。