创建javaScript 对象

Posted 2020-10-07 千彧

创建新实例person 并向其添加四个属性：

1 person=new Object();
2 person.firstname="Bill";
3 person.lastname="Gates";
4 person.age=56;
5 person.eyecolor="blue";

 

person{firstname:"john",lastname:"doe",age:50,eyecolor:"blue"};

 

1 function person(firstname,lastname,age,eyecolor){
2 this.first=firstname;
3 this.lastname=lastname;
4 this.age=age;
5 this.eyecolor=eyecol

创建javascript对象后就可以利用对象创建实例：

1 var myFather = new person("Bill","Gates",56,"blue");
2 var myMother=new person("Steve","Jobs",48,"green");

 把方法添加到JavaScript对象

 1 function person(firstname,lastname,age,eyecolor){
 2 this.firstname=firstname;
 3 this.lastname=lastname;
 4 this.age=age;
 5 this.eyecolor=eyecolor;
 6 
 7 this.changeName=changeName;
 8 function changeName(name){
 9 this.lastname=name;
10 }
11 }

javaScript  类

  javaScript类是面向对象的语言，但javaScript不使用类

 在javaScript 中，不会创建类，也不会通过类来创建对象

javaScript基于prototype（原型） 而不是基于类的

 

javaScript  for..in循环

 for...in会遍历对象中的每个属性

1 var person=={fname:"bill",lname:"gates",age"56};
2 
3 for(x in person)
4 {
5 txt=txt+person[x];
6 }
7 document.getElementById("demo").innerhtml=txt;

将会输出：

billgates56