如何将ASCII字符转换为CGKeyCode？

Question

我需要一个函数,给定一个字符,返回CGKeyCode与当前键盘布局上该字符的位置相关联的函数.例如,给定"b",kVK_ANSI_B如果使用US QWERTY,或者kVK_ANSI_N使用Dvorak ,它应该返回.

Win32 API具有VkKeyScan()用于此目的的功能; X11具有此功能XStringToKeySym().CG API中有这样的功能吗？

我需要这个来传递参数CGEventCreateKeyboardEvent().我尝试使用CGEventKeyboardSetUnicodeString(),但显然不支持修饰符标志(我需要).

我已经广泛搜索了这个但是找不到合适的答案.目前我正在使用以下代码(在线发现),它有效,但不是很优雅(而且很难解释如何简化),我宁愿不在生产代码中使用它:

#include <stdint.h>
#include <stdio.h>
#include <ApplicationServices/ApplicationServices.h>

CGKeyCode keyCodeForCharWithLayout(const char c,
                                   const UCKeyboardLayout *uchrHeader);

CGKeyCode keyCodeForChar(const char c)
{
    CFDataRef currentLayoutData;
    TISInputSourceRef currentKeyboard = TISCopyCurrentKeyboardInputSource();

    if (currentKeyboard == NULL) {
        fputs("Could not find keyboard layout\n", stderr);
        return UINT16_MAX;
    }

    currentLayoutData = TISGetInputSourceProperty(currentKeyboard,
                                                kTISPropertyUnicodeKeyLayoutData);
    CFRelease(currentKeyboard);
    if (currentLayoutData == NULL) {
        fputs("Could not find layout data\n", stderr);
        return UINT16_MAX;
    }

    return keyCodeForCharWithLayout(c,
           (const UCKeyboardLayout *)CFDataGetBytePtr(currentLayoutData));
}

/* Beware! Messy, incomprehensible code ahead!
 * TODO: XXX: FIXME! Please! */
CGKeyCode keyCodeForCharWithLayout(const char c,
                                   const UCKeyboardLayout *uchrHeader)
{
    uint8_t *uchrData = (uint8_t *)uchrHeader;
    UCKeyboardTypeHeader *uchrKeyboardList = uchrHeader->keyboardTypeList;

    /* Loop through the keyboard type list. */
    ItemCount i, j;
    for (i = 0; i < uchrHeader->keyboardTypeCount; ++i) {
        /* Get a pointer to the keyToCharTable structure. */
        UCKeyToCharTableIndex *uchrKeyIX = (UCKeyToCharTableIndex *)
        (uchrData + (uchrKeyboardList[i].keyToCharTableIndexOffset));

        /* Not sure what this is for but it appears to be a safeguard... */
        UCKeyStateRecordsIndex *stateRecordsIndex;
        if (uchrKeyboardList[i].keyStateRecordsIndexOffset != 0) {
            stateRecordsIndex = (UCKeyStateRecordsIndex *)
                (uchrData + (uchrKeyboardList[i].keyStateRecordsIndexOffset));

            if ((stateRecordsIndex->keyStateRecordsIndexFormat) !=
                kUCKeyStateRecordsIndexFormat) {
                stateRecordsIndex = NULL;
            }
        } else {
            stateRecordsIndex = NULL;
        }

        /* Make sure structure is a table that can be searched. */
        if ((uchrKeyIX->keyToCharTableIndexFormat) != kUCKeyToCharTableIndexFormat) {
            continue;
        }

        /* Check the table of each keyboard for character */
        for (j = 0; j < uchrKeyIX->keyToCharTableCount; ++j) {
            UCKeyOutput *keyToCharData =
                (UCKeyOutput *)(uchrData + (uchrKeyIX->keyToCharTableOffsets[j]));

            /* Check THIS table of the keyboard for the character. */
            UInt16 k;
            for (k = 0; k < uchrKeyIX->keyToCharTableSize; ++k) {
                /* Here's the strange safeguard again... */
                if ((keyToCharData[k] & kUCKeyOutputTestForIndexMask) ==
                    kUCKeyOutputStateIndexMask) {
                    long keyIndex = (keyToCharData[k] & kUCKeyOutputGetIndexMask);
                    if (stateRecordsIndex != NULL &&
                        keyIndex <= (stateRecordsIndex->keyStateRecordCount)) {
                        UCKeyStateRecord *stateRecord = (UCKeyStateRecord *)
                                                        (uchrData +
                        (stateRecordsIndex->keyStateRecordOffsets[keyIndex]));

                        if ((stateRecord->stateZeroCharData) == c) {
                            return (CGKeyCode)k;
                        }
                    } else if (keyToCharData[k] == c) {
                        return (CGKeyCode)k;
                    }
                } else if (((keyToCharData[k] & kUCKeyOutputTestForIndexMask)
                            != kUCKeyOutputSequenceIndexMask) &&
                           keyToCharData[k] != 0xFFFE &&
                           keyToCharData[k] != 0xFFFF &&
                           keyToCharData[k] == c) {
                    return (CGKeyCode)k;
                }
            }
        }
    }

    return UINT16_MAX;
}

是否有.)(最好)我忽略的标准功能,或b.)(几乎可以肯定)更优雅的方式写我自己的？

Answer 1

这就是我最终使用的.更清洁.

#include <CoreFoundation/CoreFoundation.h>
#include <Carbon/Carbon.h> /* For kVK_ constants, and TIS functions. */

/* Returns string representation of key, if it is printable.
 * Ownership follows the Create Rule; that is, it is the caller's
 * responsibility to release the returned object. */
CFStringRef createStringForKey(CGKeyCode keyCode)
{
    TISInputSourceRef currentKeyboard = TISCopyCurrentKeyboardInputSource();
    CFDataRef layoutData =
        TISGetInputSourceProperty(currentKeyboard,
                                  kTISPropertyUnicodeKeyLayoutData);
    const UCKeyboardLayout *keyboardLayout =
        (const UCKeyboardLayout *)CFDataGetBytePtr(layoutData);

    UInt32 keysDown = 0;
    UniChar chars[4];
    UniCharCount realLength;

    UCKeyTranslate(keyboardLayout,
                   keyCode,
                   kUCKeyActionDisplay,
                   0,
                   LMGetKbdType(),
                   kUCKeyTranslateNoDeadKeysBit,
                   &keysDown,
                   sizeof(chars) / sizeof(chars[0]),
                   &realLength,
                   chars);
    CFRelease(currentKeyboard);    

    return CFStringCreateWithCharacters(kCFAllocatorDefault, chars, 1);
}

/* Returns key code for given character via the above function, or UINT16_MAX
 * on error. */
CGKeyCode keyCodeForChar(const char c)
{
    static CFMutableDictionaryRef charToCodeDict = NULL;
    CGKeyCode code;
    UniChar character = c;
    CFStringRef charStr = NULL;

    /* Generate table of keycodes and characters. */
    if (charToCodeDict == NULL) {
        size_t i;
        charToCodeDict = CFDictionaryCreateMutable(kCFAllocatorDefault,
                                                   128,
                                                   &kCFCopyStringDictionaryKeyCallBacks,
                                                   NULL);
        if (charToCodeDict == NULL) return UINT16_MAX;

        /* Loop through every keycode (0 - 127) to find its current mapping. */
        for (i = 0; i < 128; ++i) {
            CFStringRef string = createStringForKey((CGKeyCode)i);
            if (string != NULL) {
                CFDictionaryAddValue(charToCodeDict, string, (const void *)i);
                CFRelease(string);
            }
        }
    }

    charStr = CFStringCreateWithCharacters(kCFAllocatorDefault, &character, 1);

    /* Our values may be NULL (0), so we need to use this function. */
    if (!CFDictionaryGetValueIfPresent(charToCodeDict, charStr,
                                       (const void **)&code)) {
        code = UINT16_MAX;
    }

    CFRelease(charStr);
    return code;
}

Answer 2

+ (NSString *)keyStringFormKeyCode:(CGKeyCode)keyCode
{
    // Proper key detection seems to want a switch statement, unfortunately
    switch (keyCode)
    {
        case 0: return @"a";
        case 1: return @"s";
        case 2: return @"d";
        case 3: return @"f";
        case 4: return @"h";
        case 5: return @"g";
        case 6: return @"z";
        case 7: return @"x";
        case 8: return @"c";
        case 9: return @"v";
            // what is 10?
        case 11: return @"b";
        case 12: return @"q";
        case 13: return @"w";
        case 14: return @"e";
        case 15: return @"r";
        case 16: return @"y";
        case 17: return @"t";
        case 18: return @"1";
        case 19: return @"2";
        case 20: return @"3";
        case 21: return @"4";
        case 22: return @"6";
        case 23: return @"5";
        case 24: return @"=";
        case 25: return @"9";
        case 26: return @"7";
        case 27: return @"-";
        case 28: return @"8";
        case 29: return @"0";
        case 30: return @"]";
        case 31: return @"o";
        case 32: return @"u";
        case 33: return @"[";
        case 34: return @"i";
        case 35: return @"p";
        case 36: return @"RETURN";
        case 37: return @"l";
        case 38: return @"j";
        case 39: return @"'";
        case 40: return @"k";
        case 41: return @";";
        case 42: return @"\\";
        case 43: return @",";
        case 44: return @"/";
        case 45: return @"n";
        case 46: return @"m";
        case 47: return @".";
        case 48: return @"TAB";
        case 49: return @"SPACE";
        case 50: return @"`";
        case 51: return @"DELETE";
        case 52: return @"ENTER";
        case 53: return @"ESCAPE";

            // some more missing codes abound, reserved I presume, but it would
            // have been helpful for Apple to have a document with them all listed

        case 65: return @".";

        case 67: return @"*";

        case 69: return @"+";

        case 71: return @"CLEAR";

        case 75: return @"/";
        case 76: return @"ENTER";   // numberpad on full kbd

        case 78: return @"-";

        case 81: return @"=";
        case 82: return @"0";
        case 83: return @"1";
        case 84: return @"2";
        case 85: return @"3";
        case 86: return @"4";
        case 87: return @"5";
        case 88: return @"6";
        case 89: return @"7";

        case 91: return @"8";
        case 92: return @"9";

        case 96: return @"F5";
        case 97: return @"F6";
        case 98: return @"F7";
        case 99: return @"F3";
        case 100: return @"F8";
        case 101: return @"F9";

        case 103: return @"F11";

        case 105: return @"F13";

        case 107: return @"F14";

        case 109: return @"F10";

        case 111: return @"F12";

        case 113: return @"F15";
        case 114: return @"HELP";
        case 115: return @"HOME";
        case 116: return @"PGUP";
        case 117: return @"DELETE";  // full keyboard right side numberpad
        case 118: return @"F4";
        case 119: return @"END";
        case 120: return @"F2";
        case 121: return @"PGDN";
        case 122: return @"F1";
        case 123: return @"LEFT";
        case 124: return @"RIGHT";
        case 125: return @"DOWN";
        case 126: return @"UP";

        default:

            return @"Unknown key";
            // Unknown key, bail and note that RUI needs improvement
            //fprintf(stderr, "%ld\tKey\t%c (DEBUG: %d)\n", currenttime, keyCode;
            //exit(EXIT_FAILURE;
    }
}

+ (CGKeyCode)keyCodeFormKeyString:(NSString *)keyString
{
    if ([keyString isEqualToString:@"a"]) return 0;
    if ([keyString isEqualToString:@"s"]) return 1;
    if ([keyString isEqualToString:@"d"]) return 2;
    if ([keyString isEqualToString:@"f"]) return 3;
    if ([keyString isEqualToString:@"h"]) return 4;
    if ([keyString isEqualToString:@"g"]) return 5;
    if ([keyString isEqualToString:@"z"]) return 6;
    if ([keyString isEqualToString:@"x"]) return 7;
    if ([keyString isEqualToString:@"c"]) return 8;
    if ([keyString isEqualToString:@"v"]) return 9;
    // what is 10?
    if ([keyString isEqualToString:@"b"]) return 11;
    if ([keyString isEqualToString:@"q"]) return 12;
    if ([keyString isEqualToString:@"w"]) return 13;
    if ([keyString isEqualToString:@"e"]) return 14;
    if ([keyString isEqualToString:@"r"]) return 15;
    if ([keyString isEqualToString:@"y"]) return 16;
    if ([keyString isEqualToString:@"t"]) return 17;
    if ([keyString isEqualToString:@"1"]) return 18;
    if ([keyString isEqualToString:@"2"]) return 19;
    if ([keyString isEqualToString:@"3"]) return 20;
    if ([keyString isEqualToString:@"4"]) return 21;
    if ([keyString isEqualToString:@"6"]) return 22;
    if ([keyString isEqualToString:@"5"]) return 23;
    if ([keyString isEqualToString:@"="]) return 24;
    if ([keyString isEqualToString:@"9"]) return 25;
    if ([keyString isEqualToString:@"7"]) return 26;
    if ([keyString isEqualToString:@"-"]) return 27;
    if ([keyString isEqualToString:@"8"]) return 28;
    if ([keyString isEqualToString:@"0"]) return 29;
    if ([keyString isEqualToString:@"]"]) return 30;
    if ([keyString isEqualToString:@"o"]) return 31;
    if ([keyString isEqualToString:@"u"]) return 32;
    if ([keyString isEqualToString:@"["]) return 33;
    if ([keyString isEqualToString:@"i"]) return 34;
    if ([keyString isEqualToString:@"p"]) return 35;
    if ([keyString isEqualToString:@"RETURN"]) return 36;
    if ([keyString isEqualToString:@"l"]) return 37;
    if ([keyString isEqualToString:@"j"]) return 38;
    if ([keyString isEqualToString:@"'"]) return 39;
    if ([keyString isEqualToString:@"k"]) return 40;
    if ([keyString isEqualToString:@";"]) return 41;
    if ([keyString isEqualToString:@"\\"]) return 42;
    if ([keyString isEqualToString:@","]) return 43;
    if ([keyString isEqualToString:@"/"]) return 44;
    if ([keyString isEqualToString:@"n"]) return 45;
    if ([keyString isEqualToString:@"m"]) return 46;
    if ([keyString isEqualToString:@"."]) return 47;
    if ([keyString isEqualToString:@"TAB"]) return 48;
    if ([keyString isEqualToString:@"SPACE"]) return 49;
    if ([keyString isEqualToString:@"`"]) return 50;
    if ([keyString isEqualToString:@"DELETE"]) return 51;
    if ([keyString isEqualToString:@"ENTER"]) return 52;
    if ([keyString isEqualToString:@"ESCAPE"]) return 53;

    // some more missing codes abound, reserved I presume, but it would
    // have been helpful for Apple to have a document with them all listed

    if ([keyString isEqualToString:@"."]) return 65;

    if ([keyString isEqualToString:@"*"]) return 67;

    if ([keyString isEqualToString:@"+"]) return 69;

    if ([keyString isEqualToString:@"CLEAR"]) return 71;

    if ([keyString isEqualToString:@"/"]) return 75;
    if ([keyString isEqualToString:@"ENTER"]) return 76;  // numberpad on full kbd

    if ([keyString isEqualToString:@"="]) return 78;

    if ([keyString isEqualToString:@"="]) return 81;
    if ([keyString isEqualToString:@"0"]) return 82;
    if ([keyString isEqualToString:@"1"]) return 83;
    if ([keyString isEqualToString:@"2"]) return 84;
    if ([keyString isEqualToString:@"3"]) return 85;
    if ([keyString isEqualToString:@"4"]) return 86;
    if ([keyString isEqualToString:@"5"]) return 87;
    if ([keyString isEqualToString:@"6"]) return 88;
    if ([keyString isEqualToString:@"7"]) return 89;

    if ([keyString isEqualToString:@"8"]) return 91;
    if ([keyString isEqualToString:@"9"]) return 92;

    if ([keyString isEqualToString:@"F5"]) return 96;
    if ([keyString isEqualToString:@"F6"]) return 97;
    if ([keyString isEqualToString:@"F7"]) return 98;
    if ([keyString isEqualToString:@"F3"]) return 99;
    if ([keyString isEqualToString:@"F8"]) return 100;
    if ([keyString isEqualToString:@"F9"]) return 101;

    if ([keyString isEqualToString:@"F11"]) return 103;

    if ([keyString isEqualToString:@"F13"]) return 105;

    if ([keyString isEqualToString:@"F14"]) return 107;

    if ([keyString isEqualToString:@"F10"]) return 109;

    if ([keyString isEqualToString:@"F12"]) return 111;

    if ([keyString isEqualToString:@"F15"]) return 113;
    if ([keyString isEqualToString:@"HELP"]) return 114;
    if ([keyString isEqualToString:@"HOME"]) return 115;
    if ([keyString isEqualToString:@"PGUP"]) return 116;
    if ([keyString isEqualToString:@"DELETE"]) return 117;
    if ([keyString isEqualToString:@"F4"]) return 118;
    if ([keyString isEqualToString:@"END"]) return 119;
    if ([keyString isEqualToString:@"F2"]) return 120;
    if ([keyString isEqualToString:@"PGDN"]) return 121;
    if ([keyString isEqualToString:@"F1"]) return 122;
    if ([keyString isEqualToString:@"LEFT"]) return 123;
    if ([keyString isEqualToString:@"RIGHT"]) return 124;
    if ([keyString isEqualToString:@"DOWN"]) return 125;
    if ([keyString isEqualToString:@"UP"]) return 126;

    return 0;
    //fprintf(stderr, "keyString %s Not Found. Aborting...\n", keyString);
    //exit(EXIT_FAILURE);
}

来自这里的原始代码:http: //ritter.ist.psu.edu/projects/RUI/macosx/rui.c

Answer 3

对于像我这样搜索Michael 建议的更新版本的人来说，这就是我最终自己做的事情（对我来说，它解决了一些段错误问题，可能是因为垃圾收集器正在使用这个版本完成它的工作） .

第一个函数来自Convert Virtual Key Code to unicode string。

NSString* keyCodeToString(CGKeyCode keyCode)
{
  TISInputSourceRef currentKeyboard = TISCopyCurrentKeyboardInputSource();
  CFDataRef uchr =
    (CFDataRef)TISGetInputSourceProperty(currentKeyboard,
                                         kTISPropertyUnicodeKeyLayoutData);
  const UCKeyboardLayout *keyboardLayout =
    (const UCKeyboardLayout*)CFDataGetBytePtr(uchr);

  if(keyboardLayout)
  {
    UInt32 deadKeyState = 0;
    UniCharCount maxStringLength = 255;
    UniCharCount actualStringLength = 0;
    UniChar unicodeString[maxStringLength];

    OSStatus status = UCKeyTranslate(keyboardLayout,
                                     keyCode, kUCKeyActionDown, 0,
                                     LMGetKbdType(), 0,
                                     &deadKeyState,
                                     maxStringLength,
                                     &actualStringLength, unicodeString);

    if (actualStringLength == 0 && deadKeyState)
    {
      status = UCKeyTranslate(keyboardLayout,
                                       kVK_Space, kUCKeyActionDown, 0,
                                       LMGetKbdType(), 0,
                                       &deadKeyState,
                                       maxStringLength,
                                       &actualStringLength, unicodeString);
    }
    if(actualStringLength > 0 && status == noErr)
      return [[NSString stringWithCharacters:unicodeString
                        length:(NSUInteger)actualStringLength] lowercaseString];
  }

  return nil;
}

NSNumber* charToKeyCode(const char c)
{
  static NSMutableDictionary* dict = nil;

  if (dict == nil)
  {
    dict = [NSMutableDictionary dictionary];

    // For every keyCode
    size_t i;
    for (i = 0; i < 128; ++i)
    {
      NSString* str = keyCodeToString((CGKeyCode)i);
      if(str != nil && ![str isEqualToString:@""])
      {
        [dict setObject:[NSNumber numberWithInt:i] forKey:str];
      }
    }
  }

  NSString * keyChar = [NSString stringWithFormat:@"%c" , c];

  return [dict objectForKey:keyChar];
}

我曾经NSNumber得到一个可为空的对象，charToKeyCode(c)然后可以对返回的值进行测试nil，然后使用(CGKeyCode)[charToKeyCode(c) intValue].

Answer 4

我模拟了这个不依赖于 Carbon 例程的版本。

\n

事实上，它走得更远，因为它将任何可以输入的字符映射回其虚拟键代码和修饰符组合。

\n

- (NSDictionary *)characterToKeyCode:(NSString *)character {\n    static NSDictionary * keyMapDict;\n\n    if (keyMapDict == nil) {\n        keyMapDict = [self makeKeyMap];\n    }\n\n    /*\n     The returned dictionary contains entries for the virtual key code and boolen flags\n     for modifier keys used for the character.\n     */\n    return [keyMapDict objectForKey:character];\n}\n\n- (NSDictionary *)makeKeyMap {\n    CGKeyCode keyCode;\n    CGEventRef coreEvent;\n    NSEvent * keyEvent;\n    NSUInteger modifiers = 0;\n    NSMutableDictionary * subDict, * keyMapDict;\n    NSString *character;\n    BOOL modKeyIsUsed;\n\n    static NSDictionary * modFlagDict;\n    static NSArray * modFlags;\n\n    // create dictionary of modifier names and keys. I've used all the modifiers, but I doubt theya re all needed.\n    if (modFlagDict == nil) {\n        modFlagDict = @{@"option":@(NSEventModifierFlagOption),\n                        @"shift": @(NSEventModifierFlagShift),\n                        @"function":@(NSEventModifierFlagFunction),\n                        @"control": @(NSEventModifierFlagControl),\n                        @"command":@(NSEventModifierFlagCommand)};\n        modFlags = [modFlagDict allValues];\n    }\n    keyMapDict = [NSMutableDictionary dictionary];\n\n    // run through 128 base key codes to see what they produce\n    for (keyCode = 0; keyCode < 128; ++keyCode) {\n        // create dummy NSEvent from a CGEvent for a keypress\n        coreEvent = CGEventCreateKeyboardEvent(NULL, keyCode, true);\n        keyEvent = [NSEvent eventWithCGEvent:coreEvent];\n        CFRelease(coreEvent);\n\n        if (keyEvent.type == NSEventTypeKeyDown) {\n            // this do/while loop through every permutation of modifier keys for a given key code\n            do {\n                subDict = [NSMutableDictionary dictionary];\n                // cerate dictionary containing current modifier keys and virtual key code\n                for (NSString * key in modFlagDict) {\n                    modKeyIsUsed = ([(NSNumber *)[modFlagDict objectForKey:key] unsignedLongValue] & modifiers) ? YES : NO;\n                    [subDict setObject:[NSNumber numberWithBool:modKeyIsUsed]\n                                forKey:key];\n                }\n                [subDict setObject:[NSNumber numberWithUnsignedLong:(unsigned long)keyCode]\n                            forKey:@"virtKeyCode"];\n\n                // manipulate the NSEvent to get character produce by virtual key code and modifiers\n                if (modifiers == 0) {\n                    character = [keyEvent characters];\n                } else {\n                    character = [keyEvent charactersByApplyingModifiers:modifiers];\n                }\n\n                // add sub-dictionary to main dictionary using character as key\n                if (![keyMapDict objectForKey:character]) {\n                    [keyMapDict setObject:[NSDictionary dictionaryWithDictionary:subDict]\n                                forKey:character];\n                }\n\n                // permutate the modifiers\n                modifiers = [self permutatateMods:modFlags];\n            } while (modifiers != 0);\n        }\n    }\n\n    return [NSDictionary dictionaryWithDictionary:keyMapDict];\n}\n\n- (NSUInteger)permutatateMods:(NSArray *) modFlags {\n    static NSMutableIndexSet * idxSet;\n    NSArray * modArray;\n    NSEnumerator * e;\n    NSNumber * modObj;\n    NSUInteger modifiers = 0, idx = 0;\n\n    if (idxSet == nil) {\n        idxSet = [NSMutableIndexSet indexSet];\n    }\n\n    /*\n     Starting at 0, if the index exists, remove it and move up; if the index doesn't exist, add it. Will\n     cycle through a standard binary progression. Indexes are then applied to the passed array, and the\n     selected elements are 'OR'ed together\n     */\n    BOOL doneFlag = NO;\n    while (!doneFlag) {\n        if ([idxSet containsIndex:idx]) {\n            [idxSet removeIndex:idx++];\n            continue;\n        }\n        if (idx < [modFlags count]) {\n            [idxSet addIndex:idx];\n        } else {\n            [idxSet removeAllIndexes];\n        }\n        doneFlag = YES;\n    }\n\n    modArray = [modFlags objectsAtIndexes:idxSet];\n    e = [modArray objectEnumerator];\n    while (modObj = [e nextObject]) {\n        modifiers |= [modObj unsignedIntegerValue];\n    }\n\n    return modifiers;\n}\n

\n

例如，如果您使用以下方式调用它

\n

NSDictionary * d = [self characterToKeyCode:@"\xcf\x80"];\n

\n

它将返回一个字典，内容如下：

\n

Dictionary: {\n    command = 0;\n    control = 0;\n    function = 0;\n    option = 1;\n    shift = 0;\n    virtKeyCode = 35;\n}\n

\n

其中表示“pi”符号是由虚拟键代码 35 按下选项键生成的（在标准美国键盘上：\xe2\x8c\xa5P）。

\n

Answer 5

就这个问题而言，似乎有 3 种类型的密钥可以生成CGKeyCode：

1. 纯 Unicode 字符，例如 A
2. 修饰键，例如 Shift
3. 特殊键，例如 F1。

我重复了Ted Wrigley 的答案，为所有 3 种类型创建正确的 Swift 初始化程序。CGEvent(keyboardEventSource:virtualKey:keyDown:)现在可以编写以下示例：

guard let shiftKeyCode = CGKeyCode(modifierFlag: .shift) else { fatalError() }
guard let zKeyCode = CGKeyCode(character: "z") else { fatalError() }

let event1 = CGEvent(keyboardEventSource: nil, virtualKey: shiftKeyCode, keyDown: true)
let event2 = CGEvent(keyboardEventSource: nil, virtualKey: zKeyCode, keyDown: true)
let event3 = CGEvent(keyboardEventSource: nil, virtualKey: zKeyCode, keyDown: false)
let event4 = CGEvent(keyboardEventSource: nil, virtualKey: shiftKeyCode, keyDown: false)

//
//  CGKeyCodeInitializers.swift
//
//  Created by John Scott on 09/02/2022.
//

import Foundation
import AppKit

extension CGKeyCode {
    public init?(character: String) {
        if let keyCode = Initializers.shared.characterKeys[character] {
            self = keyCode
        } else {
            return nil
        }
    }

    public init?(modifierFlag: NSEvent.ModifierFlags) {
        if let keyCode = Initializers.shared.modifierFlagKeys[modifierFlag] {
            self = keyCode
        } else {
            return nil
        }
    }
    
    public init?(specialKey: NSEvent.SpecialKey) {
        if let keyCode = Initializers.shared.specialKeys[specialKey] {
            self = keyCode
        } else {
            return nil
        }
    }
    
    private struct Initializers {
        let specialKeys: [NSEvent.SpecialKey:CGKeyCode]
        let characterKeys: [String:CGKeyCode]
        let modifierFlagKeys: [NSEvent.ModifierFlags:CGKeyCode]
        
        static let shared = Initializers()
        
        init() {
            var specialKeys = [NSEvent.SpecialKey:CGKeyCode]()
            var characterKeys = [String:CGKeyCode]()
            var modifierFlagKeys = [NSEvent.ModifierFlags:CGKeyCode]()

            for keyCode in (0..<128).map({ CGKeyCode($0) }) {
                guard let cgevent = CGEvent(keyboardEventSource: nil, virtualKey: CGKeyCode(keyCode), keyDown: true) else { continue }
                guard let nsevent = NSEvent(cgEvent: cgevent) else { continue }

                var hasHandledKeyCode = false
                if nsevent.type == .keyDown {
                    if let specialKey = nsevent.specialKey {
                        hasHandledKeyCode = true
                        specialKeys[specialKey] = keyCode
                    } else if let characters = nsevent.charactersIgnoringModifiers, !characters.isEmpty && characters != "\u{0010}" {
                        hasHandledKeyCode = true
                        characterKeys[characters] = keyCode
                    }
                } else if nsevent.type == .flagsChanged, let modifierFlag = nsevent.modifierFlags.first(.capsLock, .shift, .control, .option, .command, .help, .function) {
                    hasHandledKeyCode = true
                    modifierFlagKeys[modifierFlag] = keyCode
                }
                if !hasHandledKeyCode {
                    #if DEBUG
                    print("Unhandled keycode \(keyCode): \(nsevent)")
                    #endif
                }
            }
            self.specialKeys = specialKeys
            self.characterKeys = characterKeys
            self.modifierFlagKeys = modifierFlagKeys
        }
    }

}

extension NSEvent.ModifierFlags: Hashable { }

extension OptionSet {
    public func first(_ options: Self.Element ...) -> Self.Element? {
        for option in options {
            if contains(option) {
                return option
            }
        }
        return nil
    }
}