js delete 用法(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