javascript – 如何优化此代码?

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我有以下代码

(function($){
    $.fn.kb = function(evt,map,fn,options)
    {
        var _this = this;
        var modifiers = [17,18,19];

        function precise(a,b)
        {
            return b.Size - a.Size;
        }

        if (!this.data("Combos"))
            this.data("Combos",[]);

        var combos = this.data("Combos");
        var combo = { Size: map.Keys.length,Function: fn,Keys: map.Keys.join("").toLowerCase() };
        combos.push(combo)
        combos.sort(precise);

        map = $.extend({ Modifiers: [],Keys: [] },map);
        var KeysTimerKey = "KeysTimer" + map.Modifiers.join("") + map.Keys.join("");
        var KeysKeyKey = "Keys" + map.Modifiers.join("") + map.Keys.join("");

        options = $.extend({NoInput:false,Delay: 350,PreventDefault:false},options);

        var specialKeys = { 27: 'esc',9: 'tab',32:'space',13: 'return',8:'backspace',145: 'scroll',20: 'capslock',144: 'numlock',19:'pause',45:'insert',36:'home',46:'del',35:'end',33: 'pageup',34:'pagedown',37:'left',38:'up',39:'right',40:'down',109: '-',112:'f1',113:'f2',114:'f3',115:'f4',116:'f5',117:'f6',118:'f7',119:'f8',120:'f9',121:'f10',122:'f11',123:'f12',191: '/'};

        var FromCharCode =
            function(code)
            {
                if (specialKeys[code] != undefined)
                    return specialKeys[code];

                return String.fromCharCode(code);
            };

        this.bind
        (
            evt,function(e)
            {
                if (modifiers.indexOf(e.keyCode) == -1)
                {
                    if (options.NoInput && ["input","textarea"].indexOf(e.target.tagName.toLowerCase()) > -1) return;

                    var ctrl = map.Modifiers.join("$").match(/ctrl/i) != null;
                    var shift = map.Modifiers.join("$").match(/shift/i) != null;
                    var alt = map.Modifiers.join("$").match(/alt/i) != null;

                    if (e.ctrlKey == ctrl &&
                        e.altKey == alt &&
                        e.shiftKey == shift)
                    {
                        var key = FromCharCode(e.keyCode);
                        if (((e.ctrlKey || e.altKey || e.shiftKey) || specialKeys[e.keyCode] != undefined) &&
                            options.PreventDefault) e.preventDefault();

                        if (_this.data(KeysTimerKey) != null) clearTimeout(_this.data(KeysTimerKey));

                        var keys = _this.data(KeysKeyKey) || [];
                        keys.push(FromCharCode(e.keyCode));
                        _this.data(KeysKeyKey,keys);

                        _this.data(KeysTimerKey,setTimeout(function(){ _this.data(KeysKeyKey,""); },options.Delay));

                        var input = _this.data(KeysKeyKey).join("").toLowerCase();
                        var keys = map.Keys.join("").toLowerCase();

                        if (input.slice(-keys.length) == keys)
                        {
                            var found = -1;
                            for (var i = 0; i < combos.length; ++i)
                            {
                                if (combos[i].Keys.slice(-keys.length) == input)
                                {
                                    if (keys.length >= combos[i].Keys.length) found = i;
                                }
                            }
                        }

                        if (found >= 0)
                        {
                            combos[found].Function(e);
                            _this.data(KeysKeyKey,null);
                        }
                    }
                }
            }
        );
    }
})(jQuery);


/**/
$(window).kb("keydown",{ Modifiers: [],Keys: ["down","right","a"] },function () {alert("Hadouken");});
$(window).kb("keydown","down",function () {alert("Shouryuuken");});

它将所有组合存储在元素的数据上.当一系列键匹配时(由用户按下的所有键检查,而不是将该字符串的结尾与设置给元素的序列进行比较),我检查一个存储所有序列和回调函数的数组,看看是否有一个更加具体.如果它发现不会调用回调函数.

意思是,如果我按▼►▼►A它会触发Shouryuuken而不是Hadouken.

我想知道它是否可以更快,一直检查数组,看看是否有一些更具体的序列似乎很昂贵.

更新代码

> Using a tree

最佳答案
您可以将组合存储在树数据结构中.一个关键的组合只是通过树的潜在“路径”.然后检查组合只意味着尝试遍历树的路径:

        ▼
        |
        ► 
        /\ 
       /  \
      a    ▼
      |    |
"Hadouken" ►
           |
           a
           |
         "Shouryuuken"

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