代码如下
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var obj={ name: 'zhagnsan' , age: 19 } delete obj.name //true typeof obj.name //undefined |
通过delete操作符, 可以实现对对象属性的删除操作, 返回值是布尔
可以删除其他东西吗
1.变量
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var name = 'zs' //已声明的变量 delete name //false console.log( typeof name) //String age = 19 //未声明的变量 delete age //true typeof age //undefined this .val = 'fds' //window下的变量 delete this .val //true console.log( typeof this .val) //undefined |
已声明的变量windows下的变量可以删除, 未声明的变量不可删除
2.函数
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var fn = function (){} //已声明的函数 delete fn //false console.log( typeof fn) //function fn = function (){} //未声明的函数 delete fn //true console.log( typeof fn) //undefined |
3.数组
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var arr = [ '1' , '2' , '3' ] ///已声明的数组 delete arr //false console.log( typeof arr) //object arr = [ '1' , '2' , '3' ] //未声明的数组 delete arr //true console.log( typeof arr) //undefined var arr = [ '1' , '2' , '3' ] //已声明的数组 delete arr[1] //true console.log(arr) //['1','empty','3'] |
4.对象
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var person = { height: 180, long: 180, weight: 180, hobby: { ball: 'good' , music: 'nice' } } delete person ///false console.log( typeof person) //object var person = { height: 180, long: 180, weight: 180, hobby: { ball: 'good' , music: 'nice' } } delete person.hobby ///true console.log( typeof person.hobby) //undefined |
已声明的对象不可删除, 对象中的对象属性可以删除
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持服务器之家。
原文链接:https://blog.csdn.net/weixin_43553701/article/details/90757945