删除两个'</ p>'之间的空格

Question

I'm trying to replace double generated </p> with:

$excerpt = str_replace('</p></p>', '</p>', $excerpt);

But my PHP generates a lot of spaces between first </p> and second </p>

How to remove all spaces between the </p> tags?

My string looks like that:

<blockquote>
  <p>Text</p> <!-- here's unknown amount of space generated by php --> </p>
</blockquote>

This is related to this question on WordPress Stackexchange.

Answer 1

Using preg_replace() you can make this substitution using the following regular expression:

/<\/p>\s+<\/p>/

Your code would look something like this:

$pat = '/<\/p>\s+<\/p>/';
$replacement = '<\p>';
$excerpt = preg_replace( $pat, $replacement, $excerpt );

Lets break this regular expression:

1. <\/p> - matches a closing <\p> element (note the escaping of the slash)
2. \s+ - matches one or more whitespace characters
3. <\/p> - matches a closing <\p> element (note the escaping of the slash)

Usually you would need an add a global modifier g to the regular expression so that the substitution will occur for every occurrence of the matched pattern but the preg_replace function will perform global replacements by default.

Here is an example that you can test and play with - http://regex101.com/r/dA3kU0/2