Concat KeyDown事件(Keys)到一个C#(wpf)字符串

Question

我有一个磁卡读卡器,使用键盘输入发送数据.我正在使用KeyDown事件获取此对象(C#WPF):

KeyEventArgs e

我想把我得到的钥匙和它们串起来.我试着连续e.Key.ToString(),但这不起作用.我的输入有很多数字和符号(例如;？=等),而e.Key.ToString()的东西不起作用(它给了我一个数字的D3,而SHIFT或CTRL +另一个关键用于迹象).

我只想要字符串,所以当我使用例如Console.WriteLine时,我会得到类似的东西

;51895401051=000001341?

并不是

Oem1SHIFTD1CNTRLD2D3D2D1SHIFTD9OemQuestion ....

我尝试使用KeyConverter,但我无法解决这个问题.

有人可以帮帮我吗？

我当前的事件处理程序(无法正常工作)是:

 public static void keyPress(Object sender, KeyEventArgs e)
    {

            string keyCodeString = e.Key.ToString();

            char? key = null;

            if (keyCodeString.Length == 1)
            {
                key = keyCodeString[0];
            }
            else
            {
                if (keyCodeString.StartsWith("NumPad"))
                {
                    key = keyCodeString[keyCodeString.Length - 1];
                }
                else if (keyCodeString.StartsWith("D"))
                    key = keyCodeString[keyCodeString.Length - 1];
            }
            TypedText += key;
        }

TypedText是我想要将键连接到的字符串.输出结果如上所述.

---

我自己解决了.这是答案.GetCharFromKey下面的 函数获取一个Key(你应该发送e.Key)并返回一个char:

 public enum MapType : uint
    {
        MAPVK_VK_TO_VSC = 0x0,
        MAPVK_VSC_TO_VK = 0x1,
        MAPVK_VK_TO_CHAR = 0x2,
        MAPVK_VSC_TO_VK_EX = 0x3,
    }
    [DllImport("user32.dll")]
    public static extern bool GetKeyboardState(byte[] lpKeyState);
    [DllImport("user32.dll")]
    public static extern uint MapVirtualKey(uint uCode, MapType uMapType);
    [DllImport("user32.dll")]
    public static extern int ToUnicode(
     uint wVirtKey,
     uint wScanCode,
     byte[] lpKeyState,
     [Out, MarshalAs(UnmanagedType.LPWStr, SizeParamIndex = 4)] 
        StringBuilder pwszBuff,
     int cchBuff,
     uint wFlags);

    public static char GetCharFromKey(Key key)
    {
        char ch = ' ';

        int virtualKey = KeyInterop.VirtualKeyFromKey(key);
        byte[] keyboardState = new byte[256];
        GetKeyboardState(keyboardState);

        uint scanCode = MapVirtualKey((uint)virtualKey, MapType.MAPVK_VK_TO_VSC);
        StringBuilder stringBuilder = new StringBuilder(2);

        int result = ToUnicode((uint)virtualKey, scanCode, keyboardState, stringBuilder, stringBuilder.Capacity, 0);
        switch (result)
        {
            case -1:
                break;
            case 0:
                break;
            case 1:
                {
                    ch = stringBuilder[0];
                    break;
                }
            default:
                {
                    ch = stringBuilder[0];
                    break;
                }
        }
        return ch;
    }

Answer 1

尝试投射它：

char c = (char)e.KeyCode;