为什么我不能删除document.body属性？

Question

> delete document
  false

This I kind of understand: document is a non-configurable property of window. 我有点理解：文档是window的不可配置属性。

> delete document.body
  true
> document.body
  <body>
  ...</body>

But what witchcraft is this? 但是，这是什么巫术？

Answer 1

Because document doesn't have a "body" property. 因为文档没有“ body”属性。 Or rather it doesn't have its OWN property. 或者更确切地说，它没有OWN属性。

 console.log(document.hasOwnProperty("body")); //false //now let's mimic what we're seeing with document.body function X(){ } X.prototype.body = "Abc"; var foo = new X(); console.log(foo.body); //Abc delete foo.body; //no effect because I don't have this property. My prototype does console.log(foo.body); //Abc (still) delete foo.__proto__.body; //delete the prototype's property console.log(foo.body); //undefined (now) delete document.__proto__.__proto__.body; //delete the doc console.log(document.body); //undefined (now)

为什么我不能删除document.body属性？

问题描述

1 个解决方案

解决方案1
2 已采纳 2015-10-23 04:29:55

为什么我不能删除document.body属性？

问题描述

1 个解决方案

解决方案1 2 已采纳 2015-10-23 04:29:55

解决方案1
2 已采纳 2015-10-23 04:29:55