JavaScript定义let 的相关内容

文章 2024-07-05 来自：开发者社区

Js，定义数组的方法，let 数组名 = [数据1,数据2，........,数据n],取值方法，数组名[x],arr[0],let sum sum = sum + arr[0]，求和的写法，平均值

视频链接： JS基础Day3-40-数组的基本使用以及案例_哔哩哔哩_bilibili 取值方法 ...

文章 2022-02-16 来自：开发者社区

js中定义变量的三种方式const,val,let 的区别

js中三种定义变量的方式const， var， let的区别。   1.const定义的变量不可以修改，而且必须初始化。 1 const b = 2;//正确 2 // const b;//错误，必须初始化 3 console.log('函数外const定义b：' + b);//有输出值 4 // b = 5; 5 // console.log('函数外修改const定义b：' + b)...

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更新时间 2024-07-05 12:58:24

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