模块化编写JavaScript，在web前端程序不断扩大的时候，是一个很好的重构技术。

下面的例子有两个模块，

artDialog模块依赖jquery和jquery.artDialog库，提供了弹出错误对话框的功能。

require.config({
	paths: {
		"jquery": "../thirdParty/jquery-1.8.0.min",
		"jquery.artDialog": "../../plugin/artDialog4.1.6/jquery.artDialog"
	}
});

define("artDialog",
       ["jquery", "jquery.artDialog"],
       function ($, artDialog) {
	       return {
		       cancelText: "",

		       language: "",

		       // language should be either 'cn' or 'en'
		       init: function (language) {
			       this.language = language;
			       if (language === "cn") {
				       this.cancelText = "取消";
			       } else {
				       this.cancelText = "Cancel";
			       }
		       },

		       error: function (message) {
			       $.dialog({
				       icon: "error",
				       content: message,
				       cancelVal: this.cancelText,
				       ok: function () {
					       this.close();
				       }
			       });
		       }
	       };
       }
      );

1.require.config里面的paths 用了key: value形式，key是名称简写，path是从当前位置找到依赖文件的路径

2.define是定义模块的意思，第一个参数"artDialog"是指这个模块的名称，数组里面是本模块依赖的其他js模块，

3.RequireJS看到2定义的依赖模块后，会去加载这些js文件，加载完成后，会调用函数function($, artDialog)

4.回调函数反回一个json对象，里面有成员变量和函数。

ajaxUtility模块内部使用了artDialog模块，看看代码：

require.config({
	paths: {
		"jquery": "../thirdParty/jquery-1.8.0.min",
		"artDialog": "./dialog"
	}
});

define("ajaxUtility",
       ["jquery","artDialog"],
       function ($, artDialog) {
	       return {
		       cancelText: "",

		       language: "",

		       // language should be either 'cn' or 'en'
		       init: function (language) {
			       this.language = language;
			       artDialog.init(language);
			       if (this.language === "cn") {
				       this.cancelText = "取消";
			       } else {
				       this.cancelText = "Cancel";
			       }
		       },

		       // popup an error dialog
		       defualtErrorHandler: function (jqXHR, textStatus) {
			       artDialog.error("Ajax request got an error:" + textStatus);
		       },

		       // execute .ajax function and except the returned data type is json
		       // handler(msg) will be callback when .ajax succeeded
		       // errorHandler(jqXHR, textStatus) willl be callback if .ajax failed
		       exe: function (urlPath, asyncWay, method, dataValue, handler, errorHandler, context) {
			       var error, request;
			       if (errorHandler) {
				       error = errorHandler;				       
			       } else {
				       error = this.defaultErrorHandler;
			       }
			       request = $.ajax({
				       url: urlPath,
				       async: asyncWay,
				       type: method,
				       dataType: 'json',
				       data: dataValue
			       });

			       // request.done(handler);

			       request.done(
				       (function (ob, hdl) {
					       return function(msg) {
						       hdl(ob, msg);  
					       }
				       })(context, handler)
			       );
			       request.fail(error);
		       },

		       // post data to server using .ajax
		       // handler(msg) will be callback when .ajax succeeded
		       // errorHandler(jqXHR, textStatus) willl be callback if .ajax failed
		       post: function (urlPath, asyncWay, dataValue, handler, errorHandler, context) {
			       this.exe(urlPath, asyncWay, 'POST', dataValue, handler, errorHandler, context);
		       },

		       // call web method with GET to server using .ajax
		       // handler(msg) will be callback when .ajax succeeded
		       // errorHandler(jqXHR, textStatus) willl be callback if .ajax failed
		       get: function (urlPath,