buttonDown.js

  var keyCodes = {
    backspace: 8,
    tab: 9,
    enter: 13,
    escape: 27,
    left: 37,
    up: 38,
    right: 39,
    down: 40,
    delete: 46,
    period: 190,
    comma: 188,
    semicolon: 186,
    equal: 187,
    dash: 189,
    forwardSlash: 191,
    backSlash: 221,
    quote: 222
  };
  
  jQuery.fn.buttonDown = function(keys, onPress, other) {
    if (!_.isArray(keys)) {
      keys = [keys];
    }
    
    var onKeycodes = [];
    
    $.each(keys, function(i,key){
      if (keyCodes[key]) onKeycodes.push(keyCodes[key]);
    });
    
    if (typeof other != 'function') {
      other = function() {};
    }
    
    this.keyup(function(e){
      if (onKeycodes.indexOf(e.which) !== -1) {
        return onPress(e);
      } else {
        return other(e);
      }
    });
  };