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原文连接 http://blog.huanghanlian.com/article/5b698f22b8ea642ea9213f51

我们怎么去模拟重载，在javasceipr中我们可以通过参数的类型区别或者数量的区别，来去让同样一个函数名字，可以根据不同的参数列表的情况来去调用相应的函数。

javascript中函数类型是不确定的，并且参数的个数也是可以任意的，那么我们可以通过判断实际传入的参数的个数，来去做一个模拟的重载，

模拟重载

function person() { var args = arguments; if (typeof args[0] === 'object' && args[0]) { if (args[0].name) { this.name = args[0].name; } if (args[0].age) { this.age = args[0].age; } } else { if (args[0]) { this.name = args[0]; } if (args[1]) { this.age = args[1]; } } }; person.prototype.toString = function() { return "姓名:" + this.name + "年龄:" + this.age } var peng = new person({ name: "继小鹏", age: 23 }); console.log(peng.toString()); //姓名:继小鹏年龄:23 var peng1 = new person("是你", 23); console.log(peng1.toString()); //姓名:是你年龄:23

调用子类方法

例子1

if (!Object.create) { Object.create = function(proto) { function F() {}; F.prototype = proto; return new F(); }; } function person(name) {//基类 this.name=name; } person.prototype.init=function(){ console.log("你好"+this.name) } function student(name,classname){ //学生类 this.classname=classname; person.call(this,name); } student.prototype = Object.create(person.prototype); student.prototype.constructor = student; student.prototype.init=function(){ console.log("你好s"+this.name) } var peng=new student("继小鹏","class2"); console.log(peng); peng.init();

例子2子类调用基类方法

function person(name) {//基类 this.name=name;}function student(name,classname){ //学生类 this.classname=classname; person.call(this,name);}person.prototype.init=function(){ console.log(this.name)}student.prototype.init=function(){ person.prototype.init.apply(this,arguments);}var peng=new student("继小鹏","class2");console.log(peng);peng.init();

链式调用

function classman() {}classman.prototype.addClass = function(str) { console.log('calss' + str + 'added'); return this;}var mang = new classman();mang.addClass('classA').addClass('classB').addClass('classC')// calssclassAadded// calssclassBadded// calssclassCadded

使用jq的时候$("#id").addClass('df')
选择器做些操作后在继续addClass('df')还可以再做动作一层层链式去调用。

例子解释

function classman() {} //现定义一个构造器classmanclassman.prototype.addClass = function(str) { //给classman构造器prototype添加addClass属性方法 console.log('calss' + str + 'added'); //输出表示添加一个class return this; //return this表示返回classman的实例因为返回了实例那么紧接着后面不需要加mang.addClass('classA')直接后面加.addClass('classB').addClass('classB')就可以，每次执行完都会返回实例}var mang = new classman();mang.addClass('classA').addClass('classB').addClass('classC')// calssclassAadded// calssclassBadded// calssclassCadded

抽象类

function Detectorlse() { throw new Error("Abstract class can not be invoked directly!");}Detectorlse.detect = function() { console.log('Detcetion starting...');}Detectorlse.stop = function() { console.log('Detector stopped');}Detectorlse.init = function() { throw new Error("Error");}function linkDetector() {};linkDetector.prototype = Object.create(Detectorlse.prototype)linkDetector.prototype.constructor = linkDetector;//...add methods to LinkDetector...

defineProperty(ES5)

function Person(name) { Object.defineProperty(this, 'name', { value: name, enumerable: true });};Object.defineProperty(Person, 'arms_num', { value: 2, enumerable: true});Object.seal(Person.prototype);Object.seal(Person);function student(name, classname) { this.classname = classname; Person.call(this, name);};student.prototype = Object.create(Person.prototype);student.prototype.constructor = student;var peng = new Person('继小鹏');console.log(peng);var han = new student("汗", "class2");console.log(han);

模块化

定义简单模块化

var moduleA;moduleA=function(){ var prop=1; function func(){}; return { func:func, prop:prop }}();

定义简单模块化2

var moduleA;moduleA = new function() { var prop = 1; function func() {}; this.func = func; this.prop = prop;}();实践（探测器）