我想在 WPF 应用程序中区分(条形码)扫描仪和键盘输入。我需要的是一个在我的扫描仪提供数据时发生的事件。
在我的应用程序中,有一个特殊字段将填充来自扫描仪的输入。因此,如果用户关注了其他字段,我不想在其中插入扫描的代码,而是我的特殊字段。
首先,我将扫描仪(通过 USB 连接)的输入模式从“键盘仿真”切换为“原始”。但是我现在需要做什么?
我想在 WPF 应用程序中区分(条形码)扫描仪和键盘输入。我需要的是一个在我的扫描仪提供数据时发生的事件。
在我的应用程序中,有一个特殊字段将填充来自扫描仪的输入。因此,如果用户关注了其他字段,我不想在其中插入扫描的代码,而是我的特殊字段。
首先,我将扫描仪(通过 USB 连接)的输入模式从“键盘仿真”切换为“原始”。但是我现在需要做什么?
实现OPOS或WEPOS(网络内容不再可用)的扫描仪具有包装设备驱动程序的 COM 和/或 .Net 组件。这些组件可以在扫描数据时引发事件。这些标准也适用于更多领域,包括磁条阅读器、秤、钱箱、零钱机和 MICR(支票)阅读器。
如果未提供 xPOS 驱动程序,您可能会获得 USB/串行端口驱动程序。这使设备看起来像是通过 rs232 连接到 windows。然后您可以使用System.IO.Ports.SerialPort来编写“扫描仪”抽象。
另一种选择是获取 .sys 和 .h 文件。然后你正在做一些涉及的 PInvoke,可能还有一些 C.
我已经放弃了使用 POS for .NET 实现这一点的方法。自己做几乎更容易,因为扫描仪处理它是您感兴趣的框架的唯一相关部分。这基本上是我正在使用的:
public class RawInput
{
private static IntPtr DispatchMessage(IntPtr lParam, IEnumerable<IntPtr> fromDevices, ref object data)
{
var dataSize = UIntPtr.Zero;
if (Win32.GetRawInputData(lParam, (UIntPtr)CommandFlag.Input, IntPtr.Zero, ref dataSize, (UIntPtr)Marshal.SizeOf(typeof(Win32.RAWINPUTHEADER))) == UIntPtr.Zero)
{
var buff = Marshal.AllocHGlobal((int)dataSize);
var outSize = Win32.GetRawInputData(lParam, (UIntPtr)CommandFlag.Input, buff, ref dataSize, (UIntPtr)Marshal.SizeOf(typeof(Win32.RAWINPUTHEADER)));
Debug.Assert(outSize == dataSize);
var input = (Win32.RAWINPUT)Marshal.PtrToStructure(buff, typeof(Win32.RAWINPUT));
var hDevice = IntPtr.Zero;
if (fromDevices == null)
hDevice = input.header.hDevice;
else
hDevice = fromDevices.FirstOrDefault(h => h == input.header.hDevice);
if (hDevice != IntPtr.Zero)
{
switch ((Type)input.header.dwType)
{
case Type.HID:
var hidData = new HIDDATA()
{
count = input.hid.dwCount,
size = input.hid.dwSizeHid,
raw = new byte[input.hid.dwCount * input.hid.dwSizeHid]
};
Marshal.Copy(
new IntPtr(
buff.ToInt64() +
Marshal.SizeOf(typeof(Win32.RAWINPUTHEADER)) +
Marshal.SizeOf(typeof(Win32.RAWHID))
),
hidData.raw, 0, hidData.raw.Length
);
data = hidData;
break;
case Type.Keyboard:
data = new KEYBOARDDATA
{
makeCode = input.keyboard.MakeCode,
flags = (KeyboardFlag)input.keyboard.Flags,
vKey = input.keyboard.VKey,
message = (MessageContext)input.keyboard.Message,
extraInfo = input.keyboard.ExtraInformation
};
break;
case Type.Mouse:
var mouseData = new MOUSEDATA
{
extraInfo = input.mouse.ulExtraInformation,
flags = (MouseFlag)input.mouse.usFlags,
transitions = (MouseTransition)input.mouse.usButtonFlags,
motionX = input.mouse.lLastX,
motionY = input.mouse.lLastY
};
if (mouseData.transitions == MouseTransition.MouseWheel)
mouseData.wheelDelta = input.mouse.usButtonData;
data = mouseData;
break;
}
}
Marshal.FreeHGlobal(buff);
return hDevice;
}
else
throw new ApplicationException("An error occurred while receiving raw input data.");
}
public static bool DispatchMessage(Win32.MSG message, IEnumerable<Device> fromDevices, ref Device source, ref object data)
{
var hDevice = IntPtr.Zero;
if (message.message == MessageContext.Input)
{
if (fromDevices != null)
{
hDevice = DispatchMessage(message.lParam, fromDevices.Select(h => h.Handle), ref data);
if (hDevice != IntPtr.Zero)
source = fromDevices.First(h => h.Handle == hDevice);
}
else
{
Func<Device> getRawInputDeviceInfo = () =>
{
var name_size = UIntPtr.Zero;
Win32.GetRawInputDeviceInfo(hDevice, (UIntPtr)Win32.RIDI_DEVICENAME, IntPtr.Zero, ref name_size);
if (name_size != UIntPtr.Zero)
{
var name = Marshal.AllocHGlobal((int)name_size);
Win32.GetRawInputDeviceInfo(hDevice, (UIntPtr)Win32.RIDI_DEVICENAME, name, ref name_size);
string rid_name = (string)Marshal.PtrToStringAnsi(name);
var ridSize = (UIntPtr)Marshal.SizeOf(typeof(Win32.RID_DEVICE_INFO));
var buff = Marshal.AllocHGlobal((int)ridSize);
var outSize = Win32.GetRawInputDeviceInfo(hDevice, (UIntPtr)Win32.RIDI_DEVICEINFO, buff, ref ridSize);
Debug.Assert(outSize == ridSize);
var rid = (Win32.RID_DEVICE_INFO)Marshal.PtrToStructure(buff, typeof(Win32.RID_DEVICE_INFO));
var device = new Device()
{
Handle = hDevice,
ID = rid_name,
Type = (Type)rid.dwType,
Description = GetRawInputDeviceDescription(rid_name)
};
Marshal.FreeHGlobal(name);
return device;
}
return null;
};
hDevice = DispatchMessage(message.lParam, null, ref data);
if (hDevice != IntPtr.Zero)
source = getRawInputDeviceInfo();
}
}
return hDevice != IntPtr.Zero;
}
public static IEnumerable<Device> EnumerateDevices()
{
var ridSize = (UIntPtr)Marshal.SizeOf(typeof(Win32.RAWINPUTDEVICELIST));
var ridCnt = UIntPtr.Zero;
var list = new List<Device>();
if (Win32.GetRawInputDeviceList(IntPtr.Zero, ref ridCnt, ridSize) == UIntPtr.Zero)
{
var buff = Marshal.AllocHGlobal((int)ridCnt * (int)ridSize);
Win32.GetRawInputDeviceList(buff, ref ridCnt, ridSize);
for (int i = 0; i < (int)ridCnt; ++i)
{
var rid = (Win32.RAWINPUTDEVICELIST)Marshal.PtrToStructure(
new IntPtr((buff.ToInt64() + (int)ridSize * i)),
typeof(Win32.RAWINPUTDEVICELIST)
);
var nameSize = UIntPtr.Zero;
Win32.GetRawInputDeviceInfo(rid.hDevice, (UIntPtr)Win32.RIDI_DEVICENAME, IntPtr.Zero, ref nameSize);
if (nameSize != UIntPtr.Zero)
{
var name = Marshal.AllocHGlobal((int)nameSize);
Win32.GetRawInputDeviceInfo(rid.hDevice, (UIntPtr)Win32.RIDI_DEVICENAME, name, ref nameSize);
string rid_id = (string)Marshal.PtrToStringAnsi(name);
// filter Terminal Services and Remote Desktop devices.
if (!rid_id.ToUpper().Contains("ROOT"))
{
yield return new Device()
{
Handle = rid.hDevice,
ID = rid_id,
Type = (Type)rid.dwType,
Description = GetRawInputDeviceDescription(rid_id)
};
Marshal.FreeHGlobal(name);
}
}
}
Marshal.FreeHGlobal(buff);
}
else
throw new ApplicationException("An error occurred while retrieving a list of raw input devices");
}
public static void Register(IntPtr hwnd, REGISTERCLASS[] regs)
{
Debug.Assert(hwnd != IntPtr.Zero);
// Usage Pages and Usages:
// http://www.usb.org/developers/devclass_docs/Hut1_12.pdf
var rid = new Win32.RAWINPUTDEVICE[regs.Length];
for (int i = 0; i < regs.Length; ++i)
{
rid[i].dwFlags = (uint)regs[i].flags;
rid[i].usUsage = regs[i].usage;
rid[i].usUsagePage = (ushort)regs[i].usagePage;
rid[i].hwndTarget = hwnd;
}
if (Win32.RegisterRawInputDevices(rid, (UIntPtr)rid.Length, (UIntPtr)Marshal.SizeOf(typeof(Win32.RAWINPUTDEVICE))) == IntPtr.Zero)
throw new ApplicationException("Failed to register raw input devices");
}
public class Device
{
public static bool operator ==(Device x, Device y) { if ((object)x != null & (object)y != null) { return x.Handle == y.Handle; } else return (object)x == null && (object)y == null; }
public static bool operator !=(Device x, Device y) { return !(x == y); }
public override bool Equals(object obj) { return this == (Device)obj; }
public override int GetHashCode() { return base.GetHashCode(); }
public IntPtr Handle { get; set; }
public Type Type { get; set; }
public string ID { get; set; }
public string Description { get; set; }
}
public struct HIDDATA
{
public uint size;
public uint count;
public byte[] raw;
}
public struct KEYBOARDDATA
{
public ushort makeCode;
public KeyboardFlag flags;
public ushort vKey;
public MessageContext message;
public uint extraInfo;
}
public struct MOUSEDATA
{
public MouseFlag flags;
public MouseTransition transitions;
public ushort wheelDelta;
public int motionX;
public int motionY;
public uint extraInfo;
}
public struct REGISTERCLASS
{
public UsagePage usagePage;
public ushort usage;
public ModeFlag flags;
}
public enum KeyboardFlag : ushort
{
KeyUp = Win32.RI_KEY_BREAK,
KeyDown = Win32.RI_KEY_MAKE,
KeyLeft = Win32.RI_KEY_E0,
KeyRight = Win32.RI_KEY_E1
}
public enum MouseFlag : ushort
{
AttributesChanged = Win32.MOUSE_ATTRIBUTES_CHANGED,
MoveRelative = Win32.MOUSE_MOVE_RELATIVE,
MoveAbsolute = Win32.MOUSE_MOVE_ABSOLUTE,
VirtualDesktop = Win32.MOUSE_VIRTUAL_DESKTOP
}
public enum MouseTransition : ushort
{
LeftButtonDown = Win32.RI_MOUSE_LEFT_BUTTON_DOWN,
LeftButtonUp = Win32.RI_MOUSE_LEFT_BUTTON_UP,
MiddleButtonDown = Win32.RI_MOUSE_MIDDLE_BUTTON_DOWN,
MiddleButtonUp = Win32.RI_MOUSE_MIDDLE_BUTTON_UP,
RightButtonDown = Win32.RI_MOUSE_RIGHT_BUTTON_DOWN,
RightButtonUp = Win32.RI_MOUSE_RIGHT_BUTTON_UP,
XButton1Down = Win32.RI_MOUSE_BUTTON_4_DOWN,
XButton1Up = Win32.RI_MOUSE_BUTTON_4_UP,
XButton2Down = Win32.RI_MOUSE_BUTTON_5_DOWN,
XButton2Up = Win32.RI_MOUSE_BUTTON_5_UP,
MouseWheel = Win32.RI_MOUSE_WHEEL
}
public enum CommandFlag
{
Header = Win32.RID_HEADER,
Input = Win32.RID_INPUT
}
public enum ModeFlag : uint
{
Default = 0,
ApplicationKeys = Win32.RIDEV_APPKEYS,
CaptureMouse = Win32.RIDEV_CAPTUREMOUSE,
DeviceNotify = Win32.RIDEV_DEVNOTIFY,
Exclude = Win32.RIDEV_EXCLUDE,
ExcludeInputSink = Win32.RIDEV_EXINPUTSINK,
InputSink = Win32.RIDEV_INPUTSINK,
NoHotKeys = Win32.RIDEV_NOHOTKEYS,
NoLegacy = Win32.RIDEV_NOLEGACY,
PageOnly = Win32.RIDEV_PAGEONLY,
Remove = Win32.RIDEV_REMOVE
};
public enum UsagePage : ushort
{
Undefined = 0x00,
GenericDesktopControls = 0x01,
SimulationControls = 0x02,
VRControls = 0x03,
SportControls = 0x04,
GameControls = 0x05,
GenericDeviceControls = 0x06,
Keyboard = 0x07,
Keypad = Keyboard,
LEDs = 0x08,
Button = 0x09,
Ordinal = 0x0a,
Telephony = 0x0b,
Consumer = 0x0c,
Digitizer = 0x0d,
PIDPage = 0x0f,
Unicode = 0x10,
AlphanumericDisplay = 0x14,
MedicalInstruments = 0x40,
MonitorPage0 = 0x80,
MonitorPage1 = 0x81,
MonitorPage2 = 0x82,
MonitorPage3 = 0x83,
PowerPage0 = 0x84,
PowerPage1 = 0x85,
PowerPage2 = 0x86,
PowerPage3 = 0x87,
BarCodeScannerPages = 0x8c,
Scale = 0x8d,
MagneticStripeReadingDevices = 0x8e,
ReservedPointofSalePages = 0x8f,
CameraControlPage = 0x90,
ArcadePage = 0x91
}
/// <see cref="http://www.usb.org/developers/devclass_docs/pos1_02.pdf"/>
public enum BarCodeScannerPages : ushort
{
BarCodeScanner = 0x0002
}
public enum Type : uint
{
Mouse = Win32.RIM_TYPEMOUSE,
Keyboard = Win32.RIM_TYPEKEYBOARD,
HID = Win32.RIM_TYPEHID
}
private static string GetRawInputDeviceDescription(string deviceid)
{
string[] id = deviceid.Substring(4).Split('#');
// get registry entry by appropriate key
return ((string)Registry.LocalMachine.OpenSubKey(string.Format(
@"System\CurrentControlSet\Enum\{0}\{1}\{2}",
id[0], id[1], id[2]), false
).GetValue("DeviceDesc")).Split(';')[1];
}
}
导入使用的class Win32
Win32 API 函数并包含它们使用的一些常量:
public static class Win32
{
// mouse state flags
public const ushort MOUSE_ATTRIBUTES_CHANGED = 4, // Mouse attributes changed; application needs to query the mouse attributes.
MOUSE_MOVE_RELATIVE = 0, // Mouse movement data is relative to the last mouse position.
MOUSE_MOVE_ABSOLUTE = 1, // Mouse movement data is based on absolute position.
MOUSE_VIRTUAL_DESKTOP = 2; // Mouse coordinates are mapped to the virtual desktop (for a multiple monitor system).
// mouse transition state flags
public const ushort RI_MOUSE_LEFT_BUTTON_DOWN = 0x0001, // Left button changed to down.
RI_MOUSE_LEFT_BUTTON_UP = 0x0002, // Left button changed to up.
RI_MOUSE_MIDDLE_BUTTON_DOWN = 0x0010, // Middle button changed to down.
RI_MOUSE_MIDDLE_BUTTON_UP = 0x0020, // Middle button changed to up.
RI_MOUSE_RIGHT_BUTTON_DOWN = 0x0004, // Right button changed to down.
RI_MOUSE_RIGHT_BUTTON_UP = 0x0008, // Right button changed to up.
RI_MOUSE_BUTTON_1_DOWN = 0x0001, // RI_MOUSE_LEFT_BUTTON_DOWN
RI_MOUSE_BUTTON_1_UP = 0x0002, // RI_MOUSE_LEFT_BUTTON_UP
RI_MOUSE_BUTTON_2_DOWN = 0x0004, // RI_MOUSE_RIGHT_BUTTON_DOWN
RI_MOUSE_BUTTON_2_UP = 0x0008, // RI_MOUSE_RIGHT_BUTTON_UP
RI_MOUSE_BUTTON_3_DOWN = 0x0010, // RI_MOUSE_MIDDLE_BUTTON_DOWN
RI_MOUSE_BUTTON_3_UP = 0x0020, // RI_MOUSE_MIDDLE_BUTTON_UP
RI_MOUSE_BUTTON_4_DOWN = 0x0040, // XBUTTON1 changed to down.
RI_MOUSE_BUTTON_4_UP = 0x0080, // XBUTTON1 changed to up.
RI_MOUSE_BUTTON_5_DOWN = 0x0100, // XBUTTON2 changed to down.
RI_MOUSE_BUTTON_5_UP = 0x0200, // XBUTTON2 changed to up.
RI_MOUSE_WHEEL = 0x0400; // Raw input comes from a mouse wheel. The wheel delta is stored in usButtonData.
// keyboard scan code flags
public const ushort RI_KEY_BREAK = 1,
RI_KEY_E0 = 2,
RI_KEY_E1 = 4,
RI_KEY_MAKE = 0;
// device types
public const int RIM_TYPEMOUSE = 0,
RIM_TYPEKEYBOARD = 1,
RIM_TYPEHID = 2;
public const int RIDI_PREPARSEDDATA = 0x20000005,
RIDI_DEVICENAME = 0x20000007, // the return valus is the character length, not the byte size
RIDI_DEVICEINFO = 0x2000000b;
// mode flags
public const int RIDEV_REMOVE = 0x00000001,
RIDEV_EXCLUDE = 0x00000010,
RIDEV_PAGEONLY = 0x00000020,
RIDEV_NOLEGACY = 0x00000030,
RIDEV_INPUTSINK = 0x00000100,
RIDEV_CAPTUREMOUSE = 0x00000200, // effective when mouse nolegacy is specified, otherwise it would be an error
RIDEV_NOHOTKEYS = 0x00000200, // effective for keyboard.
RIDEV_APPKEYS = 0x00000400, // effective for keyboard.
RIDEV_EXINPUTSINK = 0x00001000,
RIDEV_DEVNOTIFY = 0x00002000,
RIDEV_EXMODEMASK = 0x000000F0;
// command flag
public const int RID_HEADER = 0x10000005,
RID_INPUT = 0x10000003;
/// <summary>
/// Contains information about a raw input device.
/// </summary>
/// <remarks>
/// typedef struct tagRAWINPUTDEVICELIST {
/// HANDLE hDevice;
/// DWORD dwType;
/// } RAWINPUTDEVICELIST, *PRAWINPUTDEVICELIST;
/// </remarks>
[StructLayout(LayoutKind.Sequential)]
public struct RAWINPUTDEVICELIST
{
public IntPtr hDevice;
[MarshalAs(UnmanagedType.U4)]
public uint dwType;
}
/// <summary>
/// Defines information for the raw input devices.
/// </summary>
/// <remarks>
/// typedef struct tagRAWINPUTDEVICE {
/// USHORT usUsagePage;
/// USHORT usUsage;
/// DWORD dwFlags;
/// HWND hwndTarget;
/// } RAWINPUTDEVICE, *PRAWINPUTDEVICE, *LPRAWINPUTDEVICE;
/// </remarks>
[StructLayout(LayoutKind.Sequential)]
public struct RAWINPUTDEVICE
{
[MarshalAs(UnmanagedType.U2)]
public ushort usUsagePage;
[MarshalAs(UnmanagedType.U2)]
public ushort usUsage;
[MarshalAs(UnmanagedType.U4)]
public uint dwFlags;
public IntPtr hwndTarget;
}
/// <summary>
/// Contains information about the state of the mouse.
/// </summary>
/// <remarks>
/// typedef struct tagRAWMOUSE {
/// USHORT usFlags;
/// union {
/// ULONG ulButtons;
/// struct {
/// USHORT usButtonFlags;
/// USHORT usButtonData;
/// };
/// };
/// ULONG ulRawButtons;
/// LONG lLastX;
/// LONG lLastY;
/// ULONG ulExtraInformation;
/// } RAWMOUSE, *PRAWMOUSE, *LPRAWMOUSE;
/// </remarks>
[StructLayout(LayoutKind.Explicit)]
public struct RAWMOUSE
{
[FieldOffset(0), MarshalAs(UnmanagedType.U2)]
public ushort usFlags;
[FieldOffset(4), MarshalAs(UnmanagedType.U4)]
public uint ulButtons;
[FieldOffset(4), MarshalAs(UnmanagedType.U2)]
public ushort usButtonFlags;
[FieldOffset(6), MarshalAs(UnmanagedType.U2)]
public ushort usButtonData;
[FieldOffset(8), MarshalAs(UnmanagedType.U4)]
public uint ulRawButtons;
[FieldOffset(12), MarshalAs(UnmanagedType.I4)]
public int lLastX;
[FieldOffset(16), MarshalAs(UnmanagedType.I4)]
public int lLastY;
[FieldOffset(20), MarshalAs(UnmanagedType.U4)]
public uint ulExtraInformation;
}
/// <summary>
/// Contains information about the state of the keyboard.
/// </summary>
/// <remarks>
/// typedef struct tagRAWKEYBOARD {
/// USHORT MakeCode;
/// USHORT Flags;
/// USHORT Reserved;
/// USHORT VKey;
/// UINT Message;
/// ULONG ExtraInformation;
/// } RAWKEYBOARD, *PRAWKEYBOARD, *LPRAWKEYBOARD;
/// </remarks>
[StructLayout(LayoutKind.Sequential)]
public struct RAWKEYBOARD
{
[MarshalAs(UnmanagedType.U2)]
public ushort MakeCode;
[MarshalAs(UnmanagedType.U2)]
public ushort Flags;
[MarshalAs(UnmanagedType.U2)]
public ushort Reserved;
[MarshalAs(UnmanagedType.U2)]
public ushort VKey;
[MarshalAs(UnmanagedType.SysUInt)]
public UIntPtr Message;
[MarshalAs(UnmanagedType.U4)]
public uint ExtraInformation;
}
/// <summary>
/// Describes the format of the raw input from a Human Interface Device (HID).
/// </summary>
/// <remarks>
/// typedef struct tagRAWHID {
/// DWORD dwSizeHid;
/// DWORD dwCount;
/// BYTE bRawData[1];
/// } RAWHID, *PRAWHID, *LPRAWHID;
/// </remarks>
[StructLayout(LayoutKind.Sequential)]
public struct RAWHID
{
[MarshalAs(UnmanagedType.U4)]
public uint dwSizeHid;
[MarshalAs(UnmanagedType.U4)]
public uint dwCount;
}
/// <summary>
/// Contains the header information that is part of the raw input data.
/// </summary>
/// <remarks>
/// typedef struct tagRAWINPUTHEADER {
/// DWORD dwType;
/// DWORD dwSize;
/// HANDLE hDevice;
/// WPARAM wParam;
/// } RAWINPUTHEADER, *PRAWINPUTHEADER;
/// </remarks>
[StructLayout(LayoutKind.Sequential)]
public struct RAWINPUTHEADER
{
[MarshalAs(UnmanagedType.U4)]
public uint dwType;
[MarshalAs(UnmanagedType.U4)]
public uint dwSize;
public IntPtr hDevice;
[MarshalAs(UnmanagedType.SysUInt)]
public UIntPtr wParam;
}
/// <summary>
/// Contains the raw input from a device.
/// </summary>
/// <remarks>
/// typedef struct tagRAWINPUT {
/// RAWINPUTHEADER header;
/// union {
/// RAWMOUSE mouse;
/// RAWKEYBOARD keyboard;
/// RAWHID hid;
/// } data;
/// } RAWINPUT, *PRAWINPUT, *LPRAWINPUT;
/// </remarks>
[StructLayout(LayoutKind.Explicit)]
public struct RAWINPUT
{
[FieldOffset(0)]
public RAWINPUTHEADER header;
#if IA32
[FieldOffset(16)]
public RAWMOUSE mouse;
[FieldOffset(16)]
public RAWKEYBOARD keyboard;
[FieldOffset(16)]
public RAWHID hid;
#elif INTEL64
[FieldOffset(24)]
public RAWMOUSE mouse;
[FieldOffset(24)]
public RAWKEYBOARD keyboard;
[FieldOffset(24)]
public RAWHID hid;
#endif
}
/// <summary>
/// Defines the raw input data coming from the specified keyboard.
/// </summary>
/// <remarks>
/// typedef struct tagRID_DEVICE_INFO_KEYBOARD {
/// DWORD dwType;
/// DWORD dwSubType;
/// DWORD dwKeyboardMode;
/// DWORD dwNumberOfFunctionKeys;
/// DWORD dwNumberOfIndicators;
/// DWORD dwNumberOfKeysTotal;
/// } RID_DEVICE_INFO_KEYBOARD, *PRID_DEVICE_INFO_KEYBOARD;
/// </remarks>
[StructLayout(LayoutKind.Sequential)]
public struct RID_DEVICE_INFO_KEYBOARD
{
[MarshalAs(UnmanagedType.U4)]
public uint dwType;
[MarshalAs(UnmanagedType.U4)]
public uint dwSubType;
[MarshalAs(UnmanagedType.U4)]
public uint dwKeyboardMode;
[MarshalAs(UnmanagedType.U4)]
public uint dwNumberOfFunctionKeys;
[MarshalAs(UnmanagedType.U4)]
public uint dwNumberOfIndicators;
[MarshalAs(UnmanagedType.U4)]
public uint dwNumberOfKeysTotal;
}
/// <summary>
/// Defines the raw input data coming from the specified mouse.
/// </summary>
/// <remarks>
/// typedef struct tagRID_DEVICE_INFO_MOUSE {
/// DWORD dwId;
/// DWORD dwNumberOfButtons;
/// DWORD dwSampleRate;
/// BOOL fHasHorizontalWheel;
/// } RID_DEVICE_INFO_MOUSE, *PRID_DEVICE_INFO_MOUSE;
/// </remarks>
[StructLayout(LayoutKind.Sequential)]
public struct RID_DEVICE_INFO_MOUSE
{
[MarshalAs(UnmanagedType.U4)]
public uint dwId;
[MarshalAs(UnmanagedType.U4)]
public uint dwNumberOfButtons;
[MarshalAs(UnmanagedType.U4)]
public uint dwSampleRate;
[MarshalAs(UnmanagedType.SysInt)]
public IntPtr fHasHorizontalWheel;
}
/// <summary>
/// Defines the raw input data coming from the specified Human Interface Device (HID).
/// </summary>
/// <remarks>
/// typedef struct tagRID_DEVICE_INFO_HID {
/// DWORD dwVendorId;
/// DWORD dwProductId;
/// DWORD dwVersionNumber;
/// USHORT usUsagePage;
/// USHORT usUsage;
/// } RID_DEVICE_INFO_HID, *PRID_DEVICE_INFO_HID;
/// </remarks>
[StructLayout(LayoutKind.Sequential)]
public struct RID_DEVICE_INFO_HID
{
[MarshalAs(UnmanagedType.U4)]
public uint dwVendorId;
[MarshalAs(UnmanagedType.U4)]
public uint dwProductId;
[MarshalAs(UnmanagedType.U4)]
public uint dwVersionNumber;
[MarshalAs(UnmanagedType.U2)]
public ushort usUsagePage;
[MarshalAs(UnmanagedType.U2)]
public ushort usUsage;
}
/// <summary>
/// Defines the raw input data coming from any device.
/// </summary>
/// <remarks>
/// typedef struct tagRID_DEVICE_INFO {
/// DWORD cbSize;
/// DWORD dwType;
/// union {
/// RID_DEVICE_INFO_MOUSE mouse;
/// RID_DEVICE_INFO_KEYBOARD keyboard;
/// RID_DEVICE_INFO_HID hid;
/// } ;
/// } RID_DEVICE_INFO, *PRID_DEVICE_INFO, *LPRID_DEVICE_INFO;
/// </remarks>
[StructLayout(LayoutKind.Explicit)]
public struct RID_DEVICE_INFO
{
[FieldOffset(0), MarshalAs(UnmanagedType.U4)]
public uint cbSize;
[FieldOffset(4), MarshalAs(UnmanagedType.U4)]
public uint dwType;
[FieldOffset(8)]
public RID_DEVICE_INFO_MOUSE mouse;
[FieldOffset(8)]
public RID_DEVICE_INFO_KEYBOARD keyboard;
[FieldOffset(8)]
public RID_DEVICE_INFO_HID hid;
}
/// <summary>
/// The POINT structure defines the x- and y- coordinates of a point.
/// </summary>
/// <remarks>
/// typedef struct tagPOINT {
/// LONG x;
/// LONG y;
/// } POINT, *PPOINT;
/// </remarks>
[StructLayout(LayoutKind.Sequential)]
public struct POINT
{
[MarshalAs(UnmanagedType.U4)]
public long x;
[MarshalAs(UnmanagedType.U4)]
public long y;
}
/// <summary>
/// Contains message information from a thread's message queue.
/// </summary>
/// <remarks>
/// typedef struct tagMSG {
/// HWND hwnd;
/// UINT message;
/// WPARAM wParam;
/// LPARAM lParam;
/// DWORD time;
/// POINT pt;
/// } MSG, *PMSG, *LPMSG;
/// </remarks>
[StructLayout(LayoutKind.Sequential)]
public struct MSG
{
public IntPtr hwnd;
[MarshalAs(UnmanagedType.SysUInt)]
public MessageContext message;
public IntPtr wParam;
public IntPtr lParam;
[MarshalAs(UnmanagedType.U4)]
public ulong time;
public POINT pt;
}
[DllImport("user32.dll")]
public static extern bool SetForegroundWindow(IntPtr hWnd);
// ...
// Import other API functions used above
// ...
}
您在为 .Net 和 USB HID 设备使用 POS 方面处于正确的轨道上。Scanner 将提供一个数据事件供您处理。您遇到的问题以及我遇到的同样问题是,在 WPF 中,您无法从 POSExplorer 对象本机接收数据事件。这是因为 POSExplorer 需要 Windows 窗体的句柄。事实证明,来自对象的 WPF 是不可接受的,因为该技术中使用了线程模型。
如果 Microsoft 可以为 WPF 创建一个 POSExplorer,那么您将被设置,但在此之前,最简单的解决方案是使用 Windows 窗体创建一个单独的项目,以便您可以处理来自 POSExplorer 的数据事件。之后,您可以处理将该信息传达给 WPF UI 的小问题。
我试图通过使用 WinAPI 让它工作。我可以枚举键盘、鼠标和其他人机界面设备:
int main()
{
UINT num_devs;
GetRawInputDeviceList(NULL, &num_devs, sizeof(RAWINPUTDEVICELIST));
RAWINPUTDEVICELIST* dev_list = new RAWINPUTDEVICELIST[num_devs];
UINT stored_devs = GetRawInputDeviceList(dev_list, &num_devs, sizeof(RAWINPUTDEVICELIST));
for( int i = 0; i < stored_devs; ++i )
{
UINT size;
RID_DEVICE_INFO dev_info;
char dev_name[256] = {0};
size = sizeof(dev_name);
GetRawInputDeviceInfoA(dev_list[i].hDevice, RIDI_DEVICENAME, dev_name, &size);
size = sizeof(RID_DEVICE_INFO);
GetRawInputDeviceInfo(dev_list[i].hDevice, RIDI_DEVICEINFO, &dev_info, &size);
std::cout << "Device Name: " << dev_name << "Device Type: ";
switch( dev_info.dwType )
{
case RIM_TYPEHID:
std::cout << "HID";
break;
case RIM_TYPEKEYBOARD:
std::cout << "Keyboard";
break;
case RIM_TYPEMOUSE:
std::cout << "Mouse";
}
std::cout << std::endl;
}
delete dev_list;
return 0;
}
但似乎 GetRawInputDeviceList 也提供 RDP 设备和其他虚拟设备。如何识别我的键盘和扫描仪?