JavaScript作用域原理预编译的相关内容

文章 2022-04-24 来自：开发者社区

JavaScript作用域原理（二）——预编译

一、变量执行之前，会被赋为undefinedfunction echo(p, html) { p.innerHTML += html + ' '; } 　　　　 var pscope2 = document.getElementById('...

文章 2017-11-09 来自：开发者社区

JavaScript作用域原理（二）——预编译

JavaScript是一种脚本语言, 它的执行过程, 是一种翻译执行的过程。并且JavaScript是有预编译过程的，在执行每一段脚本代码之前, 都会首先处理var关键字和function定义式（函数定义式和函数表达式）。   一、变量执行之前，会被赋为undefined 　　　　 fun...

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