搞定JavaScript作用域的相关内容

文章 2017-10-12 来自：开发者社区

五句话搞定JavaScript作用域

JavaScript的作用域一直以来是前端开发中比较难以理解的知识点，对于JavaScript的作用域主要记住几句话，走遍天下都不怕... 一、“JavaScript中无块级作用域” 在Java或C#中存在块级作用域，即：大括号也是一个作用域。 Java C# 在JavaScript语言中无块级作用域 1 2 3 4 5 6 7 function Main(){ ...

文章 2016-07-07 来自：开发者社区

五句话搞定JavaScript作用域

全局作用域 -> Func函数作用域 -> inner函数作用域当执行【ret();】时，由于其代指的是inner函数，此函数的作用域链在执行之前已经被定义为：全局作用域 -> Func函数作用域 -> inner函数作用域，所以，在执行【ret();】时，会根据已经存在的作用域链去寻找变量。 JavaScript的作用域一直以来是前端开发中比较难以理解的知识点，对...

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