jquery.hotkeys.js

////
// simple hotkeys plugin.
//
//   $.hotkey('a', function() { window.location = 'somewhere' })
//
//   $.hotkeys({
//     'a': function() { window.location = 'somewhere' },
//     'b': function() { alert('something else') },
//     'enter': function() { alert('you hit enter. why?') }
//   })
//
(function($) {

  // Maps event keyCode to String value
  var keyCodeToChar = {
    8: 'backspace', 9: 'tab', 13: 'enter', 16: 'shift', 17: 'ctrl',
    18: 'alt', 19: 'pause', 20: 'capslock', 27: 'esc', 32: 'space',
    33: 'pageup', 34: 'pagedown', 35: 'end', 36: 'home', 37: 'left',
    38: 'up', 39: 'right', 40: 'down', 45: 'insert', 46: 'del',
    48: '0', 49: '1', 50: '2', 51: '3', 52: '4', 53: '5', 54: '6',
    55: '7', 56: '8', 57: '9', 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: 'meta', 93: 'meta', 96: '0', 97: '1', 98: '2',
    99: '3', 100: '4', 101: '5', 102: '6', 103: '7', 104: '8',
    105: '9', 106: '*', 107: '+', 109: '-', 110: '.', 111: '/',
    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: 'numlock', 145: 'scroll', 186: ';', 187: '=',
    188: ',', 189: '-', 190: '.', 191: '/', 192: '`', 219: '[',
    220: '\\', 221: ']', 222: '\''
  }

  // Maps shift and event keyCode to String value
  var shiftKeyCodeToChar = {
    48: ')', 49: '!', 50: '@', 51: '#', 52: '$', 53: '%', 54: '^',
    55: '&', 56: '*', 57: '(', 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', 186: ':', 187: '+', 188: '<', 189: '_', 190: '>',
    191: '?', 192: '~', 219: '{', 220: '|', 221: '}', 222: '"'
  }

  // Firefox 4+ on the Mac can't seem to detect '?'
  if ($.browser.mozilla) shiftKeyCodeToChar[0] = '?'

  /** Detect pressed key combination for event
   *
   * event - jquery.Event
   *
   * Examples
   *
   *   "s"
   *   "S"
   *   "?"
   *   "ctrl+s"
   *   "ctrl+alt+del"
   *
   * Returns key character String or null.
   **/
  function eventKeyChar(event) {
    var char, shiftChar, modifiers;

    if (event.type === 'keypress') {
      char = String.fromCharCode(event.which)
    } else {
      char = keyCodeToChar[event.which]
    }

    modifiers = ''
    if (event.ctrlKey && char !== 'ctrl')
      modifiers += 'ctrl+'
    if (event.altKey && char !== 'alt')
      modifiers += 'alt+'
    if (event.metaKey && !event.ctrlKey && char !== 'meta')
      modifiers += 'meta+'

    if (event.shiftKey)
      if (event.type === 'keypress')
        return '' + modifiers + char
      else if (shiftChar = shiftKeyCodeToChar[event.which])
        return '' + modifiers + shiftChar
      else if (char === 'shift')
        return '' + modifiers + 'shift'
      else if (char)
        return '' + modifiers + 'shift+' + char
      else
        return null
    else if (char)
      return "" + modifiers + char
    else
      return null
  }


  // Setup special hotkey event listener
  //
  //   $(document).bind('keydown', '?', function() {
  //     console.log('help')
  //   })
  //
  $.each(['keydown', 'keyup', 'keypress'], function() {
    $.event.special[this] = {
      add: function(obj) {

        var handler = obj.handler,
                key = obj.data

        if (typeof obj.data === 'string') {
          obj.handler = function(event) {
            if (!event.key) event.key = eventKeyChar(event)

            // Don't call handler while typing in an input unless handler is
            // explicitly bound the to input
            if (this !== event.target && $(event.target).is(':input'))
              return

            if (event.key === key)
              return handler.apply(this, arguments)
          }
        } else {
          obj.handler = function(event) {
            if (!event.key) event.key = eventKeyChar(event)
            return handler.apply(this, arguments)
          }
        }
      }
    }
  });


  // global registered hotkeys
  globalMappings = {}

  // global handler
  $(document).bind('keydown.hotkey', function(event) {
    // Don't call handler while typing in an input
    if ($(event.target).is(':input')) return

    var handler = globalMappings[event.key]
    if (handler)
      return handler.apply(this, arguments)
  })


  // sets multiple global kotkeys
  $.hotkeys = function(mappings) {
    for (key in mappings) globalMappings[key] = mappings[key]
    return this
  }

  // sets global hotkey, accepts a function or url for `value`
  $.hotkey = function(key, value) {
    globalMappings[key] = value
    return this
  }

})(jQuery);