Regular expression to match “>”, “<”, “&” chars that appear inside XML nodes

Question

I\'m trying to write a regular expression using the PCRE library in PHP.

I need a regex to match only &, > and < cha

Answer 1

As stated by others, regular expressions don't do well with hierarchical data. Besides, if the data is improperly formatted, you can't guarantee that you'll get it right. Consider:

<xml>
    <tag>Something<br/>Something Else</tag>
</xml>

Is that <br/> supposed to read <br/>? There's no way to know because it's validly formatted XML.

If you have arbitrary data that you wish to include in your XML tree, consider using a <![CDATA[ ... ]]> block instead. It's treated the same as a text node, and the only thing you don't have to escape is the character sequence ]]>.