An object used to convert key codes to human readable strings.

JS: keyMap

function getKey(evt) {
	var 
		keyName,
		keyMap, code = evt.keyCode, 
		isShift = evt.shiftKey ? true : false, 
		isCtrl = evt.ctrlKey ? true : false, 
		isAlt = evt.altKey ? true : false;
	
	keyMap = {
		8: 'BACK_SPACE',
		9: 'TAB',
		13: 'ENTER',
		16: 'SHIFT',
		17: 'CTRL',
		18: 'ALT',
		19: 'PAUSE_BREAK',
		20: 'CAPS_LOCK',
		27: 'ESCAPE',
		33: 'PAGE_UP',
		34: 'PAGE_DOWN',
		35: 'END',
		36: 'HOME',
		37: 'LEFT',
		38: 'UP',
		39: 'RIGHT',
		40: 'DOWN',
		45: 'INSERT',
		46: 'DELETE',
		48: '0',
		49: '1',
		50: '2',
		51: '3',
		52: '4',
		53: '5',
		54: '6',
		55: '7',
		56: '8',
		57: '9',
	    	61: 'EQUALS_SIGN',
		65: 'A',
		66: 'B',
		67: 'C',
	    	68: 'D',
		69: 'E',
		70: 'F',
		71: 'G',
		72: 'H',
		73: 'I',
		74: 'J', 
		75: 'K',
		76: 'L',
		77: 'M',
		78: 'N',
		79: 'O',
		80: 'P',
		81: 'Q',
		82: 'R',
		83: 'S',
		84: 'T',
		85: 'U',
		86: 'V',
		87: 'W',
		88: 'X',
		89: 'Y',
		90: 'Z',
		91: 'LEFT_WINDOW_KEY',
		92: 'RIGHT_WINDOW_KEY',
		93: 'SELECT_KEY',
		96: 'NUMPAD_0',
		97: 'NUMPAD_1',
		98: 'NUMPAD_2',
		99: 'NUMPAD_3',
		100: 'NUMPAD_4',
		101: 'NUMPAD_5',
		102: 'NUMPAD_6',
		103: 'NUMPAD_7',
		104: 'NUMPAD_8',
		105: 'NUMPAD_9',
		106: 'MULTIPLY',
		107: 'ADD',
		109: 'SUBTRACT',
		110: 'DECIMAL_POINT',
		111: 'DIVIDE',
		112: 'F1',
		113: 'F2',
		114: 'F3',
		115: 'F4',
		116: 'F5',
		117: 'F6',
		118: 'F7',
		119: 'F8',
		120: 'F9',
		121: 'F10',
		122: 'F11',
		123: 'F12',
		144: 'NUM_LOCK',
		145: 'SCROLL_LOCK',
	    	173: 'HYPHEN',
		186: 'SEMI_COLON',
		187: 'EQUAL_SIGN',
		188: 'COMMA',
		189: 'DASH',
		190: 'PERIOD',
		191: 'FORWARD_SLASH',
		192: 'BACK_TICK', 
		219: 'OPEN_SQUARE_BRACKET',
		221: 'CLOSE_SQUARE_BRACKET',
		222: 'SINGLE_QUOTE',
	    	224: 'COMMAND'
	}
	
	if(code === 192 && isShift === true) {
		keyName = 'TILDA';
	} else if (code === 49 && isShift === true) {
		keyName = 'EXCLAMATION_POINT';
	} else if (code === 50 && isShift === true) {
		keyName = 'AT_SIGN';
	} else if (code === 51 && isShift === true) {
		keyName = 'HASHTAG';
	} else if (code === 52 && isShift === true) {
		keyName = 'DOLLAR_SIGN';
	} else if (code === 53 && isShift === true) {
		keyName = 'PERCENT';
	} else if (code === 54 && isShift === true) {
		keyName = 'CARET';
	} else if (code === 55 && isShift === true) {
		keyName = 'AMPERSAND';
	} else if (code === 56 && isShift === true) {
		keyName = 'ASTERISK';
	} else if (code === 57 && isShift === true) {
		keyName = 'OPEN_BRACKET';
	} else if (code === 58 && isShift === true) {
		keyName = 'CLOSE_BRACKET';
	} else if (code === 173 && isShift === true) {
		keyName = 'UNDERSCORE';
	} else if (code === 61 && isShift === true) {
		keyName = 'PLUS_SIGN';
	} else {
		keyName = keyMap[code];
	}
	
	return keyName;
}