js delete可以删除对象属性及变量

1,对象属性删除
function fun(){

this.name = 'mm';

}

var obj = new fun();

console.log(obj.name);//mm

delete obj.name;

console.log(obj.name); //undefined


2,变量删除
var name = 'lily';
delete name;
console.log(name); //lily
直接用delelte删除不了变量


3,删除不了原型链中的变量
fun.prototype.age = 18;
delete obj.age;
console.log(obj.age) //18