JavaScript作用域原理作用域链的相关内容

文章 2022-04-24 来自：开发者社区

JavaScript作用域原理（一）——作用域链

一、作用域的描述JavaScript权威指南中对作用域有一句很精辟的描述：“JavaScript中的函数运行在它们被定义的作用域里，而不是它们被执行的作用域里。”在JavaScript中，作用域的概念和其他语言差不多，在每次调用一个函数的时候，就会进入一个函数内的作用域，当从函数返回以后，就返回调用前的作用域。 验证下刚那句权威指南中的话：<p id="scope1" style....

文章 2017-11-15 来自：开发者社区

JavaScript作用域原理（一）——作用域链

一、作用域的描述 JavaScript权威指南中对作用域有一句很精辟的描述：“JavaScript中的函数运行在它们被定义的作用域里，而不是它们被执行的作用域里。” 在JavaScript中，作用域的概念和其他语言差不多，在每次调用一个函数的时候，就会进入一个函数内的作用域，当从函数返回以后，就返回调用前的作用域。   验证下刚那句权威指南中的话： <p id="scope1" s...

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更新时间 2022-07-27 12:10:39

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