Question

$xcatname = 'Business';
$repeatmaincitiescat = 'London, Paris, New York';

$repeatmaincitiescat = str_replace(',', ' ' . $xcatname . ',', $repeatmaincitiescat).(empty($repeatmaincitiessubcat)?'':"");

Above codes giving this result: London Business, Paris Business, New York Business

However, I want this type of output,

Business in London, Business in Paris, Business in New York

I tried a few changes but it turns out to be in error.

Answer 1

An alternative to what hakre proposed is to use regular expressions. It’s as close as you can get to your code, what you want to achieve cannot be done with a simple replace.

So, you could do (to be as close as possible to what you did):

<?php
$xcatname = 'Business';
$repeatmaincitiescat = 'London, Paris, New York';

$pattern = '/([^,]+)((,\s*)*)/';

function replace_match($matches) {
    global $xcatname;
    return $xcatname . ' in ' . $matches[1] . $matches[2];
}

$processed = preg_replace_callback($pattern, "replace_match", $repeatmaincitiescat);
// or simpler:
// $processed = preg_replace($pattern, $xcatname . " in  $1$2", $repeatmaincitiescat);
?>