JavaScript 对象

本文讨论几种js创建对象的方法，先从最好理解 
1、工厂模式开始： 

<script text="javascript">  
    function createPerson(name,age,job){   
        var o =new Obeject();   
        o.name = name;   
        o.age = age;   
        o.job = job;   
        o.sayName = function(){   
            alert(this.name);   
        };   
        return o;   
    }   
      
    var tanya = createPerson("tanya","30","female");   
    var ansel = createPerson("ansel","30","male");   
    tanya.sayName();   
    ansel.sayName();   
</script>  

2、对象模式称为构造函数模式 

<script text="javascript">  
        //执行第一句代码前，js引擎会为我们生成一个对象  
    function Person(name,age,job){   
        this.name = name;   
        this.age = age;   
        this.job = job;   
        this.sayName = function(){   
            alert(this.name);   
        };   
        //此处有一个隐藏的return语句，用于将之前生成的对象返回。  
    }   
    var tanya = new Person("tanya","30","female");   
    var ansel = new Person("ansel","30","male");   
    tanya.sayName();   
    ansel.sayName();   
</script>  

3、原型模式 

<script text="javascript">  
    function Person(){}   
      
    Person.prototype.name = name;   
    Person.prototype.age = age;   
    Person.prototype.job = job;   
    Person.prototype.sayName = function(){   
        alert(this.name);   
    };   
      
    var person = Person();   
    var person2 = Person();  
</script>  

如果使用原型对象方式，那么生成的所有对象会共享原型中的属性，这样一个对象改变了该属性也会反映到其他的对象当中。 
4、使用原型+构造函数方式来定义对象 

<script text="javascript">  
    function Person(name,age,job){   
        this.name = name;   
        this.age = age;   
        this.job = job;   
    }   
    Person.prototype.sayName= function(){   
        alert(this.name);   
    };   
    var tanya = new Person("tanya","30","female");   
    var ansel = new Person("ansel","30","male");   
    tanya.sayName();   
    ansel.sayName();   
</script>  

使用原型+构造函数方式来定义对象，对象之间的属性互不干扰，各个对象间共享同一个方法。