encodeForHTMLAttribute 与encodeForJavaScript

Question

我试图找出encodeForHTMLAttribute和之间的区别encodeForJavaScript。尽管如此，我仍然找不到将不受信任的数据用作 JavaScript 数据值的场景，这种情况在使用 转义时会破坏代码encodeForHTMLAttribute，但在使用 转义后可以安全地工作encodeForJavaScript。

我知道对于所有 javascript，建议使用encodeForJavaScript. 但我喜欢看到其中的差异。

Answer 1

你的问题的答案很无聊：事实是，将 HTML 实体编码的字符串传递给 JavaScript 很大程度上是一个未指定的操作。* JavaScript 期望传递给它的数据能够针对 JavaScript 进行转义，除了某些 API 方法之外，它没有知道你要发送什么。

HTML和JavaScript是不同的语言。如果您注意到，它们都有不同的保留字符 - 有些是相同的，这意味着它们各自都有组成语言的保留字符，在该语言中使用它们时必须特殊对待。

确保 JavaScript始终将传入代码视为数据的正确方法是对 JavaScript 进行转义。向其传递 HTMLEntity 编码的字符串可能会起作用，但我们不得不说可能是因为该行为未指定。我在开头链接的问题部分回答了您的问题的一个原因是，JavaScript 框架对您的输入进行这种处理是很常见的......所以您最好确保如果发生这种情况，数据会被适当地转义JavaScript。否则它将解开您的 HTMLEntity 编码、渲染并执行脚本代码。

我把该死的部分留到了最后： 你可以只用六个字符编写合法的 JavaScript。 HTML 编码器通常不会对这些字符进行转义。 这是关于使用像这样的 JavaScript 转义来逃避 XSS 过滤器的完整指南。 要证明它有效，请查看此处。

或者在计算机上以 HTML 文件形式自行运行：

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但是，如果您转义 Javascript 标签之间的内容<script>...它将被纯粹视为数据并且不会被执行。

*那些设计为采用 HTML 编码字符串作为输入的 JavaScript 函数除外。