php - How to replace only the last match of a string with preg_replace?

Question

I have to replace the last match of a string (for example the word foo) in HTML document. The problem is that the structure of the HTML document is always random.

I'm trying to accomplish that with preg_replace, but so far I know how to replace only the first match, but not the last one.

Thanks.

Answer 1

Use negative look after (?!...)

$str = 'text abcd text text efgh';
echo preg_replace('~text(?!.*text)~', 'bar', $str),"
";

output:

text abcd text bar efgh