Получить ключ char (значение) из кода ключа с помощью модификатора сдвига - PullRequest
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Получить ключ char (значение) из кода ключа с помощью модификатора сдвига

5 голосов
/ 26 июля 2010

Мне повезло найти String.fromCharCode(). Это помогло мне значительно. Однако я заметил, что он не учитывает модификатор shift. Я знаю свойство event.shiftKey и использую его, но сейчас мне нужно получить значение ключа (например, «A» или «a»), которое учитывает модификатор клавиши Shift. Сначала я использовал String.toLowerCase() .. Но я забыл подумать о цифровых клавишах, чтобы привести один пример: «5» (без смещения) и «%» (со смещением). Мне нужно различать два в моей программе. Какой простой способ получить значение ключевого символа?

Ответы [ 3 ]

7 голосов
/ 24 января 2011

Эта техника грубой силы не самая красивая, но, похоже, она работает. Я в поисках той же функциональности. 

function mapKeyPressToActualCharacter(isShiftKey, characterCode) {
    if ( characterCode === 27 || characterCode === 8 || characterCode === 9 || characterCode === 20 || characterCode === 16 || characterCode === 17 || characterCode === 91 || characterCode === 13 || characterCode === 92 || characterCode === 18 ) {
        return false;
    }
    if (typeof isShiftKey != "boolean" || typeof characterCode != "number") {
        return false;
    }
    var characterMap = [];
    characterMap[192] = "~";
    characterMap[49] = "!";
    characterMap[50] = "@";
    characterMap[51] = "#";
    characterMap[52] = "$";
    characterMap[53] = "%";
    characterMap[54] = "^";
    characterMap[55] = "&";
    characterMap[56] = "*";
    characterMap[57] = "(";
    characterMap[48] = ")";
    characterMap[109] = "_";
    characterMap[107] = "+";
    characterMap[219] = "{";
    characterMap[221] = "}";
    characterMap[220] = "|";
    characterMap[59] = ":";
    characterMap[222] = "\"";
    characterMap[188] = "<";
    characterMap[190] = ">";
    characterMap[191] = "?";
    characterMap[32] = " ";
    var character = "";
    if (isShiftKey) {
        if ( characterCode >= 65 && characterCode <= 90 ) {
            character = String.fromCharCode(characterCode);
        } else {
            character = characterMap[characterCode];
        }
    } else {
        if ( characterCode >= 65 && characterCode <= 90 ) {
            character = String.fromCharCode(characterCode).toLowerCase();
        } else {
            character = String.fromCharCode(characterCode);
        }
    }
    return character;
}
3 голосов
/ 12 июня 2012

Все зависит от события, к которому вы привязаны.String.fromCharCode() будет учитывать shiftKey во время события onkeypress.Однако он не будет обращать на это внимание во время события onkeydown.

1 голос
/ 10 апреля 2014

Расширяя ответ wsams, вот более полное решение, которое требует больше памяти, но более производительно 

var characterMapShift = [];
characterMapShift[8] = "";
characterMapShift[9] = "";
characterMapShift[13] = "\n";
characterMapShift[16] = "";
characterMapShift[17] = "";
characterMapShift[18] = "";
characterMapShift[19] = "";
characterMapShift[20] = "";
characterMapShift[27] = "";
characterMapShift[32] = " ";
characterMapShift[33] = "";
characterMapShift[34] = "";
characterMapShift[35] = "";
characterMapShift[36] = "";
characterMapShift[37] = "";
characterMapShift[38] = "";
characterMapShift[39] = "";
characterMapShift[40] = "";
characterMapShift[45] = "";
characterMapShift[46] = "";
characterMapShift[48] = ")";
characterMapShift[49] = "!";
characterMapShift[50] = "@";
characterMapShift[51] = "#";
characterMapShift[52] = "$";
characterMapShift[53] = "%";
characterMapShift[54] = "^";
characterMapShift[55] = "&";
characterMapShift[56] = "*";
characterMapShift[57] = "(";
characterMapShift[59] = ":";
characterMapShift[61] = "+";
characterMapShift[65] = "A";
characterMapShift[66] = "B";
characterMapShift[67] = "C";
characterMapShift[68] = "D";
characterMapShift[69] = "E";
characterMapShift[70] = "F";
characterMapShift[71] = "G";
characterMapShift[72] = "H";
characterMapShift[73] = "I";
characterMapShift[74] = "J";
characterMapShift[75] = "K";
characterMapShift[76] = "L";
characterMapShift[77] = "M";
characterMapShift[78] = "N";
characterMapShift[79] = "O";
characterMapShift[80] = "P";
characterMapShift[81] = "Q";
characterMapShift[82] = "R";
characterMapShift[83] = "S";
characterMapShift[84] = "T";
characterMapShift[85] = "U";
characterMapShift[86] = "V";
characterMapShift[87] = "W";
characterMapShift[88] = "X";
characterMapShift[89] = "Y";
characterMapShift[90] = "Z";
characterMapShift[91] = "";
characterMapShift[92] = "";
characterMapShift[93] = "";
characterMapShift[96] = "0";
characterMapShift[97] = "1";
characterMapShift[98] = "2";
characterMapShift[99] = "3";
characterMapShift[100] = "4";
characterMapShift[101] = "5";
characterMapShift[102] = "6";
characterMapShift[103] = "7";
characterMapShift[104] = "8";
characterMapShift[105] = "9";
characterMapShift[106] = "*";
characterMapShift[107] = "+";
characterMapShift[109] = "_";
characterMapShift[107] = "+";
characterMapShift[111] = "/";
characterMapShift[112] = "";
characterMapShift[113] = "";
characterMapShift[114] = "";
characterMapShift[115] = "";
characterMapShift[116] = "";
characterMapShift[117] = "";
characterMapShift[118] = "";
characterMapShift[119] = "";
characterMapShift[120] = "";
characterMapShift[121] = "";
characterMapShift[122] = "";
characterMapShift[123] = "";
characterMapShift[144] = "";
characterMapShift[145] = "";
characterMapShift[186] = ":";
characterMapShift[187] = "+";
characterMapShift[188] = "<";
characterMapShift[189] = "_";
characterMapShift[190] = ">";
characterMapShift[191] = "?";
characterMapShift[192] = "~";
characterMapShift[219] = "{";
characterMapShift[220] = "|";
characterMapShift[221] = "}";
characterMapShift[222] = "\"";

var characterMap = [];
characterMap[8] = "";
characterMap[9] = "";
characterMap[13] = "\n";
characterMap[16] = "";
characterMap[17] = "";
characterMap[18] = "";
characterMap[19] = "";
characterMap[20] = "";
characterMap[27] = "";
characterMap[32] = " ";
characterMap[33] = "";
characterMap[34] = "";
characterMap[35] = "";
characterMap[36] = "";
characterMap[37] = "";
characterMap[38] = "";
characterMap[39] = "";
characterMap[40] = "";
characterMap[45] = "";
characterMap[46] = "";
characterMap[48] = "0";
characterMap[49] = "1";
characterMap[50] = "2";
characterMap[51] = "3";
characterMap[52] = "4";
characterMap[53] = "5";
characterMap[54] = "6";
characterMap[55] = "7";
characterMap[56] = "8";
characterMap[57] = "9";
characterMap[59] = ";";
characterMap[61] = "=";
characterMap[65] = "a";
characterMap[66] = "b";
characterMap[67] = "c";
characterMap[68] = "d";
characterMap[69] = "e";
characterMap[70] = "f";
characterMap[71] = "g";
characterMap[72] = "h";
characterMap[73] = "i";
characterMap[74] = "j";
characterMap[75] = "k";
characterMap[76] = "l";
characterMap[77] = "m";
characterMap[78] = "n";
characterMap[79] = "o";
characterMap[80] = "p";
characterMap[81] = "q";
characterMap[82] = "r";
characterMap[83] = "s";
characterMap[84] = "t";
characterMap[85] = "u";
characterMap[86] = "v";
characterMap[87] = "w";
characterMap[88] = "x";
characterMap[89] = "y";
characterMap[90] = "z";
characterMap[91] = "";
characterMap[92] = "";
characterMap[93] = "";
characterMap[96] = "0";
characterMap[97] = "1";
characterMap[98] = "2";
characterMap[99] = "3";
characterMap[100] = "4";
characterMap[101] = "5";
characterMap[102] = "6";
characterMap[103] = "7";
characterMap[104] = "8";
characterMap[105] = "9";
characterMap[106] = "*";
characterMap[107] = "+";
characterMap[109] = "_";
characterMap[107] = "+";
characterMap[111] = "/";
characterMap[112] = "";
characterMap[113] = "";
characterMap[114] = "";
characterMap[115] = "";
characterMap[116] = "";
characterMap[117] = "";
characterMap[118] = "";
characterMap[119] = "";
characterMap[120] = "";
characterMap[121] = "";
characterMap[122] = "";
characterMap[123] = "";
characterMap[144] = "";
characterMap[145] = "";
characterMap[186] = ";";
characterMap[187] = "=";
characterMap[188] = ",";
characterMap[189] = "-";
characterMap[190] = ".";
characterMap[191] = "/";
characterMap[192] = "`";
characterMap[219] = "[";
characterMap[220] = "\\";
characterMap[221] = "]";
characterMap[222] = "'";

function mapKeyPressToActualCharacter(isShiftKey, characterCode) {
    if (typeof isShiftKey != "boolean" || typeof characterCode != "number") {
        return false;
    }

    if (isShiftKey) {
        return characterMapShift[characterCode];
    } else {
        return characterMap[characterCode];
    }
}
...