JS对象入门

1.对象

属性和方法

2.创建对象

①直接创建

person=new Object();person.firstname="Bill";person.lastname="Gates";person.age=56;person.eyecolor="blue";

替代语法

person={firstname:"John",lastname:"Doe",age:50,eyecolor:"blue"};

②构造函数

function person(firstname,lastname,age,eyecolor){this.firstname=firstname;this.lastname=lastname;this.age=age;this.eyecolor=eyecolor;this.changeName=changeName;function changeName(name){this.lastname=name;}}

<pre style="margin-top: 10px; margin-bottom: 0px; padding: 10px; border: 1px dotted rgb(119, 136, 85); font-family: Consolas, 'Courier New', Courier, monospace; width: 685px; background: rgb(245, 245, 245);">var myFather=new person("Bill","Gates",56,"blue");var myMother=new person("Steve","Jobs",48,"green");

方法也是属性。

avaScript 基于 prototype，而不是基于类的

3.for...in

循环遍历对象的属性

var person={fname:"Bill",lname:"Gates",age:56};for (x in person)  {  txt=txt + person[x];  }

对象名类似数组索引。