这个JS文件有什么用呢？

 
var AM;!function(exports) {    AM = exports.fn.use;
    AM.add = exports.fn.add;
    AM.ready = exports.fn.ready;
    AM.delay = exports.fn.delay;
    AM.setMods = exports.util.setMods;
    
    AM(function() {
        var mods = [
                {mod: 'editor', name: 'core', file: '/editor/core/'},
                {mod: 'swfupload', reqs: ['swfupload', 'swfupload.queue', 'fileprogress', 'handlers'], file: '/swfupload/'},
                {mod: 'swfupload.photo', reqs: ['swfupload.photo', 'swfupload.queue.photo', 'fileprogress.photo', 'handlers.photo'], file: '/swfupload/'}
            ];
            
        var i, j, mod, reqs, req;
            
        for (i = 0; mod = mods[i]; i++) {
            reqs = mod.reqs || [];
            
            if (reqs.length) {
                for (j = 0; req = reqs[j]; j++) {
                    AM.add(req, {path: [exports.data.base, mod.file || '', req, '.js'].join(''), type: 'js'});
                }
            }
            
            AM.add(mod.mod, {path: [exports.data.base, mod.file || '', mod.name || mod.mod, '.js'].join(''), type: 'js', requires: reqs});
        }
    });
    
}((function() {
    
    var AM = {};    /**
     * data
     * @type {Object}
     */
    AM._data = {
    
        base: AM_Config.baseUrl,
        
        root: AM_Config.baseUrl.replace(/\/forum/, ''),
    
        version: AM_Config.baseVersion || '',
        
        jsFiles: document.getElementsByTagName('script'),
        
        isReady: false,        loaded: {},        loadingQueue: {},        readyList: [],        globalList: [],
        
        config: {
        
            autoLoad: true,
            
            coreLib: [],
            
            mods: {}
            
        }
    
    };    /**
     * util
     * @type {Object}
     */
    AM._util = {};    /**
     * fn
     * @type {Object}
     */
    AM._fn = {};
    
    !function(data, util) {
    
        var mods = data.config.mods,
            core = data.config.coreLib,
            global = data.globalList;
    
        /**
         * isUrl
         * @param  {String} url
         * @return {Boolean}
         */
        util.isUrl = function(url) {
            return /^(https|http).*$/gi.test(url);
        };
    
        /**
         * isArray
         * @param  {Array} e
         * @return {Boolean}
         */
        util.isArray = function(e) {
            return e.constructor === Array;
        };
        
        /**
         * setMods
         * @param  {String} key
         * @param  {Object} val
         */
        util.setMods = function (key, val) {
            mods[key] = val;
        };        /**
         * getMods
         * @param  {String} key
         * @return {Object}
         */
        util.getMods = function (key) {
            return mods[key];
        };
        
        /**
         * addCore
         * @param  {String} url
         */
        util.addCore = function (url) {
            core.push(url);
        };
        
        /**
         * addGlobal
         * @param  {String} url
         */
        util.addGlobal = function(url) {
            global.push(url);
        };
        
        /**
         * compile
         * @param  {Array} arr
         * @return {Array}
         */
        util.compile = function(arr) {
            var rjs = /\.js$/,
                rroot = /^\$/,
                i, item, name, file;
            
            for (i = 0; item = arr[i]; i++) {
                var _item = item;                if (typeof item === 'string' && !util.isUrl(item)) {
                
                    if (util.getMods(_item) !== undefined) {
                        continue;
                    }
                    
                    item = item.replace(rjs, '');
                    
                    if (item.split('/').length > 1) {
                        name = [item, 'js'].join('.');
                    } else {
                        item = item.split('.');
                        name = item.pop();
                        name = [item.length ? item.join('.') : 'App', name, 'js'].join('.');
                    }
                    
                    file = [data.base, '/', name, data.version];
                    
                    if (rroot.test(name)) {
                        file[0] = data.root;
                        file[2] = file[2].replace(rroot, '');
                    }
                    
                    file = file.join('');
                    
                    util.setMods(_item, {path: file, type: 'js'});
                    
                }
            }
            
            return arr;
        };
        
    }(AM._data, AM._util);
    
    !function(data, util, fn) {
    
        var _doc = document,            _win = window,
        
            _Queue = function(e) {
                if (!e || !util.isArray(e)) {
                    return;
                }                this.queue = e;
                this.current = null;
            };        _Queue.prototype = {            _interval: 10,            start: function() {
                var o = this;
                this.current = this.next();                if (!this.current) {
                    this.end = true;
                    return;
                }                this.run();
            },            run: function() {
                var o = this, mod, currentMod = this.current;                if (typeof currentMod === 'function') {
                    currentMod();
                    this.start();
                    return;
                } else if (typeof currentMod === 'string') {
                    if (data.config.mods[currentMod]) {
                        mod = data.config.mods[currentMod];
                        fn.load(mod.path, mod.type, mod.charset, function(e) {
                            o.start();
                        }, o);
                    } else if (/hm.baidu.com\/h\.js/i.test(currentMod)) {
                        fn.load(currentMod, 'js', '', function(e, o) {
                            o.start();
                        }, o);
                    } else if (/\.js/i.test(currentMod)) {
                        fn.load(currentMod + data.version, 'js', '', function(e, o) {
                            o.start();
                        }, o);
                    } else if (/\.css/i.test(currentMod)) {
                        fn.load(currentMod + data.version, 'css', '', function(e, o) {
                            o.start();
                        }, o);
                    } else {
                        this.start();
                    }
                }
            },            next: function() { 
                return this.queue.shift(); 
            }
        };
        
        fn.fire = function() {
            data.isReady = true;
            if (data.readyList.length > 0) {
                fn.use.apply(this, data.readyList);
                data.readyList = [];
            }
        };
    
        fn.load = function(url, type, charset, cb, context) {
            var refFile = data.jsFiles[0];
JavaScript函数对象

解决方案 »

  1.   


                if (!url) {
                    return;
                }
                
                if (data.loaded[url]) {
                    data.loadingQueue[url] = false;
                    if (cb) {
                        cb(url, context);
                    }
                    return;
                }
                
                if (data.loadingQueue[url]) {
                    setTimeout(function() {
                        fn.load(url, type, charset, cb, context);
                    }, 1);
                    return;
                }            data.loadingQueue[url] = true;            var n, t = type || url.toLowerCase().substring(url.lastIndexOf('.js') + 1);            t = t.replace(data.version, '');            if (t === 'js') {
                    n = _doc.createElement('script');
                    n.setAttribute('type', 'text/javascript');
                    n.setAttribute('src', url);
                    n.setAttribute('async', true);
                } else if (t === 'css') {
                    n = _doc.createElement('link');
                    n.setAttribute('type', 'text/css');
                    n.setAttribute('rel', 'stylesheet');
                    n.setAttribute('href', url);
                    data.loaded[url] = true;
                }            if (charset) {
                    n.charset = charset;
                }            if (t === 'css') {
                    refFile.parentNode.insertBefore(n, refFile);
                    if (cb) {
                        cb(url, context);
                    }
                    return;
                }            n.onload = n.onreadystatechange = function() {
                    if (!this.readyState || this.readyState === 'loaded' || this.readyState === 'complete') {
                        
                        data.loaded[this.getAttribute('src')] = true;                    if (cb) {
                            cb(this.getAttribute('src'), context);
                        }                    n.onload = n.onreadystatechange = null;
                    }
                };            refFile.parentNode.insertBefore(n, refFile);
            };
            
            fn.calculate = function(e) {
                if (!e || !util.isArray(e)) {
                    return;
                }            var i = 0,
                    item,
                    result = [],
                    mods = data.config.mods,
                    depeList = [],
                    hasAdded = {},
                    getDepeList = function(e) {
                        var i = 0, m, reqs;
                        
                        if (hasAdded[e]) {
                            return depeList;
                        }
                        hasAdded[e] = true;                    if (mods[e].requires) {
                            reqs = mods[e].requires;
                            for (; typeof (m = reqs[i++]) !== 'undefined';) {
                                if (mods[m]) {
                                    getDepeList(m);
                                    depeList.push(m);
                                } else {
                                    depeList.push(m);
                                }
                            }
                            return depeList;
                        }
                        return depeList;
                    };            for (; typeof (item = e[i++]) !== 'undefined'; ) {
                    if (mods[item] && mods[item].requires && mods[item].requires[0]) {
                        depeList = [];
                        hasAdded = {};
                        result = result.concat(getDepeList(item));
                    }
                    result.push(item);
                }            return result;
            };
            
            fn.onDOMContentLoaded = function() {
                if (_doc.addEventListener) {
                    _doc.removeEventListener('DOMContentLoaded', fn.onDOMContentLoaded, false);
                    fn.fire();
                } else if (_doc.attachEvent && _doc.readyState === 'complete') {
                    _doc.detachEvent('onreadystatechange', fn.onDOMContentLoaded);
                    fn.fire();
                }
            };
            
            fn.doScrollCheck = function() {
                if (data.isReady) {
                    return;
                }            try {
                    _doc.documentElement.doScroll('left');
                } catch (err) {
                    return _win.setTimeout(fn.doScrollCheck, 1);
                }            fn.fire();
            };
        
            fn.bindReady = function() {
                if (_doc.readyState === 'complete') {
                    return _win.setTimeout(fn.fire, 1);
                }            var toplevel = false;            if (_doc.addEventListener) {
                    _doc.addEventListener('DOMContentLoaded', fn.onDOMContentLoaded, false);
                    _win.addEventListener('load', fn.fire, false);
                } else if (_doc.attachEvent) {
                    _doc.attachEvent('onreadystatechange', fn.onDOMContentLoaded);
                    _win.attachEvent('onload', fn.fire);                try {
                        toplevel = (_win.frameElement === null);
                    } catch (err) {}                if (document.documentElement.doScroll && toplevel) {
                        fn.doScrollCheck();
                    }
                }
            };
        
            fn.use = function() {
                var args = [].slice.call(arguments), thread;
                
                util.compile(args);            if (data.globalList.length > 0) {
                    args = data.globalList.concat(args);
                }            if (data.config.autoLoad) {
                    args = data.config.coreLib.concat(args);
                }
                
                if (data.isReady) {
                    thread = new _Queue(fn.calculate(args));
                    thread.start();
                } else {
                    data.readyList = data.readyList.concat(args);
                }
            };
            
            fn.add = function(sName, oConfig) {
                if (!sName || !oConfig || !oConfig.path) {
                    return;
                }
                data.config.mods[sName] = oConfig;
            };
            
            fn.delay = function() {
                var args = [].slice.call(arguments),
                    delay = args.shift();
                
                _win.setTimeout(function() {
                    fn.use.apply(this, args);
                }, delay);
            };
            
            fn.ready = function() {
                var args = [].slice.call(arguments);
                
                if (data.isReady) {
                    return fn.use.apply(this, args);
                }
                data.readyList = data.readyList.concat(args);
            };
            
            util.addCore(data.base + '/lib/jquery.js');
            util.addGlobal(data.base + '/App.component.js');
            
            fn.bindReady();
            
        }(AM._data, AM._util, AM._fn);
        
        var exports = {};
        
        exports.name = 'AM.js';
        exports.version = '2.2';
        
        exports.fn = AM._fn;
        exports.data = AM._data;
        exports.util = AM._util;
        
        return exports;})());