JavaScript也具有对象，用于将属性和函数放在一起，虽然他是面向对象的语言，但是不具备类和接口。
1、对象的定义
（1)字面量方式
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Java Script</title>
<script type="text/javascript">
</script>
</head>
<body bgcolor="aquamarine">
<script>
var Person = {
name: "Li",//属性
age: 12,
per: function() {//函数
alert("你好");
}
}
console.log(Person.name);
console.log(Person.age);
Person.per();
</script>
</body>
</html>
（2）var 变量名=new Object（）方式
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Java Script</title>
<script type="text/javascript">
</script>
</head>
<body bgcolor="aquamarine">
<script>
var Person = new Object();
Person.name="Li";
Person.age=12;
Person.per= function() {
alert("你好");
}
console.log(Person.name);
console.log(Person.age);
Person.per();
</script>
</body>
</html>
（3）构造函数方式创建对象
构造函数是一种特殊的函数，主要用来初始化对象，可以把一些公共的属性和方法抽取出来，然后封装到函数内
<script> function User(username,password){ this.username=username; this.password=password; this.hobby=function(hobby){ console.log(hobby); } } var u1= new User('zhai','123456'); u1.hobby("rap"); var u2= new User('zhang','666666'); u2.hobby("篮球"); console.log(u1); console.log(typeof u1); console.log(u2); </script>
2、对象属性的访问
<!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>Java Script</title> <script type="text/javascript"> </script> </head> <body bgcolor="aquamarine"> <script> var Person = new Object(); Person.name="Li"; Person.age=12; Person.per= function() { alert("你好"); } console.log(Person["name"]); console.log(Person.age); </script> </body> </html>
一共有两中访问方法：
（1）直接加点访问
（2）采用方括号访问，此方法对于属性名不规则的情况依旧适用。
3、对象的基本操作
（1）添加
<!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>Java Script</title> <script type="text/javascript"> </script> </head> <body bgcolor="aquamarine"> <script> var Person = new Object(); Person.name="Li"; Person.age=12; Person.per= function() { alert("你好"); } Person.sex="男"; console.log(Person.sex); </script> </body> </html>
（2）修改
<!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>Java Script</title> <script type="text/javascript"> </script> </head> <body bgcolor="aquamarine"> <script> var Person = new Object(); Person.name="Li"; Person.age=12; Person.per= function() { alert("你好"); } Person.name="zhai"; console.log(Person.name); </script> </body> </html>
4、遍历对象
（1）for... in
输出属性名：
<script>
var Person = new Object();
Person.name="Li";
Person.age=12;
Person.per= function() {
alert("你好");
}
Person.name="zhai";
for(var a in Person){
console.log(a);
}
</script>
输出属性值：
<script>
var Person = new Object();
Person.name="Li";
Person.age=12;
Person.per= function() {
alert("你好");
}
Person.name="zhai";
for(var a in Person){
console.log(Person[a]);
}
</script>
