JavaScript const赋值的相关内容

文章 2023-03-06 来自：开发者社区

JavaScript const 变量必须在声明时赋值

在声明时赋值JavaScript const 变量必须在声明时赋值：不正确const PI;PI = 3.14159265359;正确const PI = 3.14159265359;不是真正的常数关键字 const 有一定的误导性。它没有定义常量值。它定义了对值的常量引用。因此，我们不能更改常量原始值，但我们可以更改常量对象的属性。原始值如果我们将一个原始值赋给常量，我们就不能改变原始值：实例....

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....

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更新时间 2024-04-30 13:25:08

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