php 如何用一个 <br /> 标签正则表达式替换多个 <br /> 标签？
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How to Regex-replace multiple <br /> tags with one <br /> tag?
提问by Weblurk
I want <br /><br />to turn into <br />
我想<br /><br />变成<br />
What's the pattern for this with regex?
正则表达式的模式是什么？
Note: The <br />tags can occur more than 2 times in a row.
注意：<br />标签可以连续出现 2 次以上。
回答by FtDRbwLXw6
$html = preg_replace('#(<br */?>\s*)+#i', '<br />', $html);
This will catch any combination of <br>, <br/>, or <br />with any amount or type of whitespace between them and replace them with a single <br />.
这将捕获, 或之间的任何数量或类型的空格的任何组合<br>，并将它们替换为单个.<br/><br /><br />
回答by Williham Totland
You coulduse s/(<br \/>)+/<br \/>/, but if you are trying to use regex on HTML you are likely doing something wrong.
您可以使用s/(<br \/>)+/<br \/>/，但如果您尝试在 HTML 上使用正则表达式，您可能会做错事。
Edit:A slightly more robust pattern you could use if you have mixed breaks:
编辑：如果您有混合休息，您可以使用稍微更强大的模式：
/(<br\ ?\/?>)+/
/(<br\ ?\/?>)+/
This will catch <br/>and <br>as well, which might be useful in certain cases.
这将捕获<br/>，<br>并且在某些情况下可能有用。
回答by AndrewMcLagan
The answer from @FtDRbwLXw6 is great although it does not account for spaces. We can extend this regex to include that as well:
@FtDRbwLXw6 的答案很好，尽管它没有考虑 空格。我们可以扩展这个正则表达式以包含它：
$html = preg_replace('#(<br *\/?>\s*( )*)+#', '<br>', $html);
回答by m.edmondson
(<br />)+
(<br />)+
Will match them so you could use preg_replaceto replace them (remember to correctly escape characters).
将匹配它们，以便您可以preg_replace用来替换它们（记住正确转义字符）。
