javascript创建对象的6种方式

/*1、工厂模式*/
function createPerson(name,age,job) {
    var o = new object();
    o.name = name;
    o.age = age;
    o.job = job;
    o.setName = function(newName) {
        this.name = newName;
    };
    return o;
}
var person1 = createPerson("zcj", 21, "Soft Engineer");
/*
 问题：只能创建多个相似的对象，不能识别对象
*/

/*2、构造函数模式*/
function Person(name,age,job) {
    this.name = name;
    this.age = age;
    this.job = job;
    this.setName = function(newName) {
	this.name = newName;
    }
}
var person1 = new Person("zcj", 21, "Soft Engineer");
/*
 问题：每个方法都要在实例上重新创建一遍
*/

/*3、原型模式*/
function Person() {    
}

person.prototype.name = "zcj";
person.prototype.age = 21;
person.prototype.job = "Soft Engineer";
person.prototype.sayName = function() {
    alert(this.name);
};

var person1 = new Person();
var person2 = new Person();
alert(person1.sayName == person2.sayName);   //true

person1.name = "Greg";
alert(person1.name);  //"Greg"
alert(person2.name);    //"zcj"

delete person1.name;
alert(person1.name);   //"zcj"
/*
 问题：所有实例在默认情况下取得相同的属性值；对于引用类型的属性，为所有实例共享（这是不期望的）
*/

/*4、组合使用构造函数模式和原型模式*/
function Person(name,age,job) {
    this.name = name;
    this.age = age;
    this.job = job;
    friends = ["Shelby","Court"]
}
Person.prototype = {
    constructor:Person,
    sayName: function() {
	alert(this.name);
    }
}
var person1 = new Person("zcj",21,"Soft Engineer");
var person2 = new Person("Gerg",27,"Doctor");
person1.friends.push("Van");
alert(person1.friends);   //"Shellby,Court,Van"
alert(person2.friends);   //"Shellby,Court"
alert(person1.friends === person2.friends);   //false
alert(person1.sayName === person2.sayName);   //true
/*
 说明：使用最广泛，认同度最高的创建自定义类型的方法
*/

/*5、动态原型模式*/
function Person(name,age,job) {
    this.name = name;
    this.age = age;
    this.job = job;
    if(typeof this.sayName != "function") {
        Person.prototype.sayName = function() {
	    alert(this.name);
        };
    }
}
var friend = new Person("zcj", 21, "Soft Engineer");
friend.sayName();
/*
 说明：将所有信息封装在构造函数中，通过检查某个应该存在的方法是否有效，决定是否需要初始化
*/

/*6、寄生构造函数模式*/
function Person(name,age,job) {
    var o = new object();
    o.name = name;
    o.age = age;
    o.job = job;
    o.setName = function(newName) {
        this.name = newName;
    };
    return o;
}
var person1 = new Person("zcj", 21, "Soft Engineer");
person1.setName("Gerg");
alert(person1.name);   //"Gerg"
/*
 说明：与工厂模式区别：1、实例化对象要使用new;2、改包装函数为构造函数（函数名第一个字母大写）
*/