红外条码扫描器的另类使用C#版.doc

红外条码扫描器的另类使用C#版 3年前写了一篇USB口的红外条形码扫描器的另类使用，不过相关代码是VB编写，在这几年之间，有许多网友提出需要C#版的，起初还以为由VB修改C#应该很容易，最近研究了一下，发现C#和VB调用API的机制还是有所不同的，在迁移的过程中还是会遇到不少问题，所以我专门抽时间做了一个基于C#的程序。 【目前的条形码扫描器有点类似外接键盘（其实从消息传送上它就相当于一个键盘），把输入焦点定位到可输入的控件上，一扫描相应的条形码信息就输入到文本框中去了，但是如果没有输入焦点，或另一个不相干的程序获得输入焦点，那就有点乱套了。我想实现的是，不管什么情况，只要扫描器一工作，我的程序就能自动激活，并能获得当前输入的条形码信息。 实现思路：我用的是litele牌的USB口的红外条形码扫描器，仔细分析了一下，扫描成功后，以键盘按键消息的形式把条形码输入信息通知给系统。这样通过键盘钩子就可以方便的获得该信息了。但是，怎样区分信息是键盘还是条形码输入的哪？很简单，条形码扫描器在很短的时间内输入了至少3个字符以上信息，并且以“回车”作为结束字符，在这种思想指引下，很完美的实现了预定功能。】 VB相关的代码请见：/yefanqiu/archive/2006/08/30/1144881.aspx 窗体相关代码：view plaincopy to clipboardprint?1020304050607080901001101201301401501 using System; 2 using System.Collections.Generic; 3 using System.ComponentModel; 4 using System.Data; 5 using System.Drawing; 6 using System.Text; 7 using System.Windows.Forms; 8 9 namespace ReadBadCode 10 11 public partial class frmTest : Form 12 13 BarCodeHook BarCode = new BarCodeHook(); 14 public frmTest() 15 16 InitializeComponent(); 17 BarCode.BarCodeEvent += new BarCodeHook.BarCodeDelegate(BarCode_BarCodeEvent); 18 19 20 private delegate void ShowInfoDelegate(BarCodeHook.BarCodes barCode); 21 private void ShowInfo(BarCodeHook.BarCodes barCode) 22 23 if (this.InvokeRequired) 24 25 this.BeginInvoke(new ShowInfoDelegate(ShowInfo), new object barCode ); 26 27 else 28 29 textBox1.Text = barCode.KeyName; 30 textBox2.Text = barCode.VirtKey.ToString(); 31 textBox3.Text = barCode.ScanCode.ToString(); 32 textBox4.Text = barCode.AscII.ToString(); 33 textBox5.Text = barCode.Chr.ToString(); 34 textBox6.Text = barCode.IsValid ? barCode.BarCode : ; 35 36 37 38 void BarCode_BarCodeEvent(BarCodeHook.BarCodes barCode) 39 40 ShowInfo(barCode); 41 42 43 private void frmTest_Load(object sender, EventArgs e) 44 45 BarCode.Start(); 46 47 48 private void frmTest_FormClosed(object sender, FormClosedEventArgs e) 49 50 BarCode.Stop(); 51 52 53 private void textBox6_TextChanged(object sender, EventArgs e) 54 55 if (textBox6.Text.Length 0) 56 57 MessageBox.Show(textBox6.Text); 58 59 60 61 62 63 BarCodeHook 类：view plaincopy to clipboardprint?10203040506070809010011012013014015064 using System; 65 using System.Collections.Generic; 66 using System.Text; 67 using System.Runtime.InteropServices; 68 using System.Reflection; 69 70 namespace ReadBadCode 71 72 public class BarCodeHook 73 74 public delegate void BarCodeDelegate(BarCodes barCode); 75 public event BarCodeDelegate BarCodeEvent; 76 77 public struct BarCodes 78 79 public int VirtKey; /虚拟码 80 public int ScanCode; /扫描码 81 public string KeyName; /键名 82 public uint AscII; /AscII 83 public char Chr; /字符 84 85 public string BarCode; /条码信息 86 public bool IsValid; /条码是否有效 87 public DateTime Time; /扫描时间 88 89 90 private struct EventMsg 91 92 public int message; 93 public int paramL; 94 public int paramH; 95 public int Time; 96 public int hwnd; 97 98 99 DllImport(user32.dll, CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall) 100 private static extern int SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hInstance, int threadId); 101 102 DllImport(user32.dll, CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall) 103 private static extern bool UnhookWindowsHookEx(int idHook); 104 105 DllImport(user32.dll, CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall) 106 private static extern int CallNextHookEx(int idHook, int nCode, Int32 wParam, IntPtr lParam); 107 108 DllImport(user32, EntryPoint = GetKeyNameText) 109 private static extern int GetKeyNameText(int lParam, StringBuilder lpBuffer, int nSize); 110 111 DllImport(user32, EntryPoint = GetKeyboardState) 112 private static extern int GetKeyboardState(byte pbKeyState); 113 114 DllImport(user32, EntryPoint = ToAscii) 115 private static extern bool ToAscii(int VirtualKey, int ScanCode, byte lpKeyState, ref uint lpChar, int uFlags); 116 117 delegate int HookProc(int nCode, Int32 wParam, IntPtr lParam); 118 BarCodes barCode = new BarCodes(); 119 int hKeyboardHook = 0; 120 string strBarCode = ; 121 122 private int KeyboardHookProc(int nCode, Int32 wParam, IntPtr lParam) 123 124 if (nCode = 0) 125 126 EventMsg msg = (EventMsg)Marshal.PtrToStructure(lParam, typeof(EventMsg); 127 128 if (wParam = 0x100) /WM_KEYDOWN = 0x100 129 130 barCode.VirtKey = msg.message & 0xff; /虚拟码 131 barCode.ScanCode = msg.paramL & 0xff; /扫描码 132 133 StringBuilder strKeyName = new StringBuilder(255); 134 if (GetKeyNameText(barCode.ScanCode * 65536, strKeyName, 255) 0) 135 136 barCode.KeyName = strKeyName.ToString().Trim(new char , 0 ); 137 138 else 139 140 barCode.KeyName = ; 141 142 143 byte kbArray = new byte256; 144 uint uKey = 0; 145 GetKeyboardState(kbArray); 146 if (ToAscii(barCode.VirtKey, barCode.ScanCode, kbArray, ref uKey, 0) 147 148 barCode.AscII = uKey; 149 barCode.Chr = Convert.ToChar(uKey); 150 151 152 if (DateTime.Now.Subtract(barCode.Time).TotalMilliseconds 50) 153 154 strBarCode = barCode.Chr.ToString(); 155 156 else 157 158 if (msg.message & 0xff) = 13 & strBarCode.Length 3) /回车 159 160 barCode.BarCode = strBarCode; 161 barCode.IsValid = true; 162 163 strBarCode += barCode.Chr.ToString(); 164 165 166 barCode.Time = DateTime.Now; 167 if (BarCodeEvent != null) BarCodeEvent(barCode); /触发事件 168 barCode.IsValid = false; 169 170 171 return CallNextHookEx(hKeyboardHook, nCode, wParam, lParam); 172 173 174 / 安装钩子 175 public bool Start() 176 177 if (hKeyboardHook = 0) 178 179 /WH_KEYBOARD_LL = 13 180 hKeyboardHook = SetWindowsHookEx(13, new HookProc(KeyboardHookProc), Marshal.GetHINSTANCE(Assembly