您正在寻找 /.../ s 修饰符，称为 dotall 修饰符。它强制点。也匹配新行，默认情况下它不执行。

You are looking for the /.../s modifier, also known as the dotall modifier. It forces the dot . to also match newlines, which it does not do by default.

坏消息是JavaScript 中不存在（从ES2018开始，见下文）。好消息是你可以通过使用字符类（例如 \s ）及其否定（ \S $）来解决它。 c $ c>），像这样：

The bad news is that it does not exist in JavaScript (it does as of ES2018, see below). The good news is that you can work around it by using a character class (e.g. \s) and its negation (\S) together, like this:

[\s\S]

因此，在您的情况下，正则表达式将成为：

So in your case the regex would become:

/<div class="box-content-5">[\s\S]*<h1>([^<]+?)<\/h1>/i

从ES2018开始，JavaScript支持 s （dotAll）标志，所以在现代环境中你的正则表达式可能就像你写的一样，但是带有 s 标志结束（而不是 m ; m 改变 ^ 的方式和 $ 工作，而不是。）：

As of ES2018, JavaScript supports the s (dotAll) flag, so in a modern environment your regular expression could be as you wrote it, but with an s flag at the end (rather than m; m changes how ^ and $ work, not .):

/<div class="box-content-5">.*<h1>([^<]+?)<\/h1>/is