オブジェクトの作成方法

var person = new Object();
person.name = "Nicholas";
person.age = "29";
person.job = "Software Engineer";

person.sayName = function(){
    alert(this.name);
};

//对象字面量写法
var person = {
    name: "Nicholas",
    age: "29",
    job: "Software Engineer",
    
    sayName: function(){
        alert(this.name);
    }
};

function createPerson (name, age , job) {
    var o = new Object();
    o.name = name;
    o.age = age;
    o.job = job;
    o.sayName = function(){
         alert(this.name);
    };
    return o;
}

var person1 = createPerson("Nicholas", "29", "Software Engineer");
var person2 = createPerson("Greg", "27", "Doctor");

function Person(name, age, job) {
    this.name = name;
    this.age = age;
    this.job = job;
    this.sayName = function(){
        alert(this.name);
    };
}
//构造函数使用new操作符来调用
var person1 = new Person("Nicholas", "29", "Software Engineer");
var person2 = new Person("Greg", "27", "Doctor");

//不同实例上的同名函数是不相等的
alert(person1.sayName == person2.sayName);        //false

//可以把函数定义转移到构造函数外来解决这个问题
function Person(name, age, job) {
    this.name = name;
    this.age = age;
    this.job = job;    
　  this.sayName = sayName;
}
function sayName() {
    alert(this.name);
}

function Person() {
}
Person.prototype.name = "Nicholas";
Person.prototype.age = "29";
Person.prototype.job = "Software Engineer";
Person.prptptype.sayName = function(){
    alert(this.name);
};

var person1 = new Person();
person1.sayName();        //"Nicholas"

var person2 = new Person();
person2.sayName();        //"Nicholas"

alert(person1.sayName == person2.sayName);        //true

//更简单的原型语法
function Person() {
}
Person.prototype = {
    constructor : Person,        //以对象字面量形式创建新对象，constructor不再指向Person，在此特意设置为Person
    name : "Nicholas",
    age : "29",
    job : "Software Engineer",
    sayName : function () {
        alert(this.name);
    }
};