Question

original string: $text = "aaaa aaaasomething someaaaa aaaa 89aaaa aaaathis"

final result i need: $textresult = "aaaa aaaasomething some4a aaaa 894a aaaathis"

I mean: I want to replace any string on the text that ends with aaaa to 4a. But only if it is an ending and not an isolated string like aaaa or a string that starts with aaaa.

I presume str_replace or preg_replace could eventually do this in a single code line but do not have idea how to do it.

Thanks in advance!

Answer 1

$textresult = preg_replace('/\Baaaa\b/', '4a', $text);

\B only matches between two alphanumeric characters, i. e. in the middle of a word.

\b only matches between alphanumeric and non-alphanumeric characters, i. e. at the start or end of a word.