Ext 2.0动态加载JS工具类（经典）
转自：
http://www.ajaxbbs.net/post/extjs/ExtJs-dynamic-LoadJS-Class.html
ScriptLoader = function () { this .timeout = 30 ; this .scripts = []; this .disableCaching = false ; this .loadMask = null ; }; ScriptLoader.prototype = { showMask: function () { if (!this .loadMask) { this .loadMask = new Ext.LoadMask(Ext.getBody()); this .loadMask.show (); } }, hideMask: function () { if (this .loadMask) { this .loadMask.hide (); this .loadMask = null ; } }, processSuccess: function (response) { this .scripts[response.argument.url] = true ; window .execScript ? window .execScript(response.responseText) : window .eval(response.responseText); if (response.argument.options.scripts.length == 0 ) { this .hideMask(); } if (typeof response.argument.callback == 'function' ) { response.argument.callback.call(response.argument.scope); } }, processFailure: function (response) { this .hideMask(); Ext.MessageBox.show ({title: 'Application Error' , msg: 'Script library could not be loaded.' , closable: false , icon: Ext.MessageBox.ERROR, minWidth: 200 }); setTimeout (function () { Ext.MessageBox.hide (); }, 3000 ); }, load : function (url, callback) { var cfg, callerScope; if (typeof url == 'object' ) { // must be config object cfg = url; url = cfg.url; callback = callback || cfg.callback; callerScope = cfg.scope; if (typeof cfg.timeout != 'undefined' ) { this .timeout = cfg.timeout; } if (typeof cfg.disableCaching != 'undefined' ) { this .disableCaching = cfg.disableCaching; } } if (this .scripts[url]) { if (typeof callback == 'function' ) { callback.call(callerScope || window ); } return null ; } this .showMask(); Ext.Ajax.request({ url: url, success: this .processSuccess, failure: this .processFailure, scope: this , timeout: (this .timeout*1000 ), disableCaching: this .disableCaching, argument: { 'url' : url, 'scope' : callerScope || window , 'callback' : callback, 'options' : cfg } }); } }; ScriptLoaderMgr = function () { this .loader = new ScriptLoader(); this .load = function (o) { if (!Ext.isArray(o.scripts)) { o.scripts = [o.scripts]; } o.url = o.scripts.shift(); if (o.scripts.length == 0 ) { this .loader.load (o); } else { o.scope = this ; this .loader.load (o, function () { this .load (o); }); } }; }; ScriptMgr = new ScriptLoaderMgr();
构建一个one page one application的应用，动态的加载js组件是关键，虽然看到了5，6种解决方案，可是还是没办法做的很通用，作为一个项目组件。突然发现ExtJs的官方论坛确实是个好地方，由很多好用的资源，可是E文还是没有母语看这舒服，把最好的方案记录下。原文地址：http://extjs.com/forum/showthread.php?t=37897
使用示例:
ScriptMgr.load ({ scripts: ['/js/other-prerequisite.js' , '/js/other.js' ], callback: function () { var other = new OtherObject(); alert(other); //just loaded } });