使用C#捕获usb扫描枪扫描二维码、条形码结果（支持中文）
扫描枪扫描结果获取类
public class ScanerHook
{
public delegate void ScanerDelegate(ScanerCodes codes);
public event ScanerDelegate ScanerEvent;
delegate int HookProc(int nCode, Int32 wParam, IntPtr lParam);
private int hKeyboardHook = 0;
private ScanerCodes codes = new ScanerCodes();
private HookProc hookproc;
[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
private static extern int SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hInstance, int threadId);
[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
private static extern bool UnhookWindowsHookEx(int idHook);
[DllImport("user32", EntryPoint = "GetKeyNameText")]
private static extern int GetKeyNameText(int IParam, StringBuilder lpBuffer, int nSize);
[DllImport("user32", EntryPoint = "GetKeyboardState")]
private static extern int GetKeyboardState(byte[] pbKeyState);
[DllImport("user32", EntryPoint = "ToAscii")]
private static extern bool ToAscii(int VirtualKey, int ScanCode, byte[] lpKeySate, ref uint lpChar, int uFlags);
[DllImport("kernel32.dll")]
public static extern IntPtr GetModuleHandle(string name);
public ScanerHook()
{
}
public bool Start()
{
if (hKeyboardHook == 0)
{
hookproc = new HookProc(KeyboardHookProc);
//GetModuleHandle 函数 替代 Marshal.GetHINSTANCE
//防止在 framework4.0中 注册钩子不成功
IntPtr modulePtr = GetModuleHandle(Process.GetCurrentProcess().MainModule.ModuleName);
//WH_KEYBOARD_LL=13
//全局钩子 WH_KEYBOARD_LL
// hKeyboardHook = SetWindowsHookEx(13, hookproc, Marshal.GetHINSTANCE(Assembly.GetExecutingAssembly().GetModules()[0]), 0);
hKeyboardHook = SetWindowsHookEx(13, hookproc, modulePtr, 0);
}
return (hKeyboardHook != 0);
}
public bool Stop()
{
if (hKeyboardHook != 0)
{
return UnhookWindowsHookEx(hKeyboardHook);
}
return true;
}
private int KeyboardHookProc(int nCode, Int32 wParam, IntPtr lParam)
{
EventMsg msg = (EventMsg)Marshal.PtrToStructure(lParam, typeof(EventMsg));
codes.Add(msg);
if (ScanerEvent != null && msg.message == 13 && msg.paramH > 0 && !string.IsNullOrEmpty(codes.Result))
{
ScanerEvent(codes);
}
return 0;
}
public class ScanerCodes
{
private int ts = 500; // 指定输入间隔为500毫秒以内时为连续输入
private List<List<EventMsg>> _keys = new List<List<EventMsg>>();
private List<int> _keydown = new List<int>(); // 保存组合键状态
private List<string> _result = new List<string>(); // 返回结果集
private List<string> _alt = new List<string>(); // 保存alt按下时的各键位
private DateTime _last = DateTime.Now;
private byte[] _state = new byte[256];
private string _key = string.Empty;
private string _cur = string.Empty;
public EventMsg Event
{
get
{
if (_keys.Count == 0)
{
return new EventMsg();
}
else
{
return _keys[_keys.Count - 1][_keys[_keys.Count - 1].Count - 1];
}
}
}
public List<int> KeyDowns
{
get
{
return _keydown;
}
}
public DateTime LastInput
{
get
{
return _last;
}
}
public byte[] KeyboardState
{
get
{
return _state;
}
}
public int KeyDownCount
{
get
{
return _keydown.Count;
}
}
public string Result
{
get
{
if (_result.Count > 0)
{
return _result[_result.Count - 1].Trim();
}
else
{
return null;
}
}
}
public string CurrentKey
{
get
{
return _key;
}
}
public string CurrentChar
{
get
{
return _cur;
}
}
public bool isShift
{
get
{
return _keydown.Contains(160) || _keydown.Contains(161);
}
}
public bool isAlt
{
get
{
return _keydown.Contains(164) || _keydown.Contains(165);
}
}
public bool isControl
{
get
{
return _keydown.Contains(162) || _keydown.Contains(163);
}
}
public void Clear()
{
_keys.Clear();
_result.Clear();
}
public void Add(EventMsg msg)
{
#region 记录按键信息
// 首次按下按键
if (_keys.Count == 0)
{
_keys.Add(new List<EventMsg>());
_keys[0].Add(msg);
_result.Add(string.Empty);
}
// 未释放其他按键时按下按键
else if (_keydown.Count > 0)
{
_keys[_keys.Count - 1].Add(msg);
}
// 单位时间内按下按键
else if (((TimeSpan)(DateTime.Now - _last)).TotalMilliseconds < ts)
{
_keys[_keys.Count - 1].Add(msg);
}
// 从新记录输入内容
else
{
_keys.Add(new List<EventMsg>());
_keys[_keys.Count - 1].Add(msg);
_result.Add(string.Empty);
}
if (_keys.Count > 10)
{
_keys.RemoveAt(0);
}
#endregion
_last = DateTime.Now;
#region 获取键盘状态
// 记录正在按下的按键
if (msg.paramH < 128 && !_keydown.Contains(msg.message))
{
_keydown.Add(msg.message);
}
// 清除已松开的按键
if (msg.paramH > 127 && _keydown.Contains(msg.message))
{
_keydown.Remove(msg.message);
}
#endregion
#region 计算按键信息
int v = msg.message & 0xff;
int c = msg.paramL & 0xff;
StringBuilder strKeyName = new StringBuilder(500);
if (GetKeyNameText(c * 65536, strKeyName, 255) > 0)
{
_key = strKeyName.ToString().Trim(new char[] { ' ', '\0' });
GetKeyboardState(_state);
if (_key.Length == 1 && msg.paramH < 128)
{
// 根据键盘状态和shift缓存判断输出字符
_cur = ShiftChar(_key, isShift, _state).ToString();
_result[_result.Count - 1] += _cur;
}
else if (msg.paramH < 128 && isAlt)
{
_alt.Add(_key);
}
else if (msg.paramH > 127 && (msg.message == 164 || msg.message == 165))
{
string composite = string.Empty;
for (int i = 0; i < _alt.Count; i++)
{
composite += _alt[i];
}
composite = Regex.Replace(composite, @"[^0-9]+", "");
string hex = Convert.ToInt32(composite).ToString("x");
if (hex.Length % 2 == 1)
{
hex = "0" + hex;
}
string str = Regex.Replace(hex, @"([0-9a-f]{2})", "%$1");
_cur = System.Web.HttpUtility.UrlDecode(str, Encoding.GetEncoding(936));
_result[_result.Count - 1] += _cur;
_alt.Clear();
}
else
{
_cur = string.Empty;
}
}
#endregion
}
private char ShiftChar(string k, bool isShiftDown, byte[] state)
{
bool capslock = state[0x14] == 1;
bool numlock = state[0x90] == 1;
bool scrolllock = state[0x91] == 1;
bool shiftdown = state[0xa0] == 1;
char chr = (capslock ? k.ToUpper() : k.ToLower()).ToCharArray()[0];
if (isShiftDown)
{
if (chr >= 'a' && chr <= 'z')
{
chr = (char)((int)chr - 32);
}
else if (chr >= 'A' && chr <= 'Z')
{
chr = (char)((int)chr + 32);
}
else
{
string s = "`1234567890-=[];',./";
string u = "~!@#$%^&*()_+{}:\"<>?";
if (s.IndexOf(chr) >= 0)
{
return (u.ToCharArray())[s.IndexOf(chr)];
}
}
}
return chr;
}
}
public struct EventMsg
{
public int message;
public int paramL;
public int paramH;
public int Time;
public int hwnd;
}
}使用示例
直接实例化一个ScanerHook，然后Start开始监听，对ScanerEvent进行接收就可以了
ScanerHook listener = new ScanerHook();
listener.ScanerEvent += (codes) =>{
Console.WriteLine(codes.Result);
};
//启用
listener.Start();
//停止
listener.Stop();