function overLoading() {// 根据arguments.length，对不同的值进行不同的操作switch(arguments.length) {case 0:/*操作1的代码写在这里*/break;case 1:/*操作2的代码写在这里*/break;case 2:/*操作3的代码写在这里*///后面还有很多的case......
}}

var people = {values: ["Dean Edwards", "Sam Stephenson", "Alex Russell", "Dean Tom"]
};

addMethod(people, "find", function() {}); /*不传参*/
addMethod(people, "find", function(a) {}); /*传一个*/
addMethod(people, "find", function(a, b) {}); /*传两个*/

function addMethod(object, name, fn) {var old = object[name]; //把前一次添加的方法存在一个临时变量old里面object[name] = function() { // 重写了object[name]的方法// 如果调用object[name]方法时，传入的参数个数跟预期的一致，则直接调用if(fn.length === arguments.length) {return fn.apply(this, arguments);// 否则，判断old是否是函数，如果是，就调用old} else if(typeof old === "function") {return old.apply(this, arguments);}}
}

//addMethod
function addMethod(object, name, fn) {var old = object[name];object[name] = function() {if(fn.length === arguments.length) {return fn.apply(this, arguments);} else if(typeof old === "function") {return old.apply(this, arguments);}}
}var people = {values: ["Dean Edwards", "Alex Russell", "Dean Tom"]
};/* 下面开始通过addMethod来实现对people.find方法的重载 */// 不传参数时，返回peopld.values里面的所有元素
addMethod(people, "find", function() {return this.values;
});// 传一个参数时，按first-name的匹配进行返回
addMethod(people, "find", function(firstName) {var ret = [];for(var i = 0; i < this.values.length; i++) {if(this.values[i].indexOf(firstName) === 0) {ret.push(this.values[i]);}}return ret;
});// 传两个参数时，返回first-name和last-name都匹配的元素
addMethod(people, "find", function(firstName, lastName) {var ret = [];for(var i = 0; i < this.values.length; i++) {if(this.values[i] === (firstName + " " + lastName)) {ret.push(this.values[i]);}}return ret;
});// 测试：
console.log(people.find()); //["Dean Edwards", "Alex Russell", "Dean Tom"]
console.log(people.find("Dean")); //["Dean Edwards", "Dean Tom"]
console.log(people.find("Dean Edwards")); //["Dean Edwards"]