JavaScript面目的相关内容

问答 2022-05-31 来自：开发者社区

12.1 作用域12.1.1 定义作用域是指在程序中定义变量的区域，该位置决定了变量的生命周期。简言之作用域就是变量与函数的可访问范围，即作用域控制着变量和函数的可见性和生命周期。12.1.2 分类在ES6阶段之前，作用域分为两种：全局作用域和函数作用域；进行ES6之后，作用域分为：全局作用域、函数作用域和块级作用域。全局作用域在该作用域中的对象在代码的任何地方都能访问，其生命周期伴随着页面的生....

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更新时间 2024-02-07 09:37:02

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