Question

I have the following sample set of data:

<p>first line\n
second line\n
third line\n</p>
first line\n
second line\n
third line\n

Using regex, how could I match on the newline characters, but only when they are within the paragraph tags.

This code would be used within php.

Answer 1

You could split this in two regex’s. First split on your <p> tags (<p>.*?</p>) , then match on newline from the result.

Divide and conquer. Several small regex’s will often perform faster than huge ones.

I assume you have total control over the html and know it’s well formed. Because using regex on html is a no-no in most cases. Use a DOM parser instead.