JavaScript es6 const 的相关内容

文章 2023-12-13 来自：开发者社区

JavaScript开发中ES6+新特性：介绍一下let和const与var的区别。

在ES6及之后的版本中，引入了 let 和 const 关键字，它们与 var 关键字在变量声明和作用域方面有一些重要的区别。 1. let 和 var 的区别：变量作用域： var：使用 var 声明的变量是函数作用域（function-scoped），即它们只在声明它们的函数内...

文章 2022-10-09 来自：开发者社区

JavaScript在ES6中的新变量 let 、const和解构赋值

目录前言一、let变量1.块级作用域2.不存在变量提升3.使用let变量需要先声明后使用4.不能重复声明5.总结二、const变量1.块级作用域2.声明常量必须赋值3.常量赋值不能修改三、let、const和var的区别四、结构赋值数组1.数组的结构赋值2.二维数组3.省略变量4.合并数组5.默认值对象前言为什么学习es6每一次标准的诞生都意味着语言的完善，功能的加强。JavaScript语言本....

问答 2016-03-13 来自：开发者社区

JavaScript ES6中var、let、const分别什么时候使用？

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更新时间 2024-02-27 09:34:28

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