Replace all domain including subdomain name using PHP with Regex

Question

I am using preg_replace or str_replace in PHP to replace all the domain name including www

$string = ' https://example.com, https://www.example.com, https://subdomain.example.com ';
$olddomain= "example.com";
$newdomain = "stackoverflow.com";

$output = str_replace($olddomain, $newdomain, $string);
$output = preg_replace('#(www[.])?[.]' . $olddomain. '#', $newdomain, $body);

echo $output;

My expectation:

https://example.com -> https://stackoverflow.com

https://www.example.com -> https://stackoverflow.com

https://subdomain.example.com -> https://subdomain.example.com

Answer 1

No need for a regex, just pass the www. with the other change in into str_replace(). Remember str_replace() accepts an array of things to "change from" and "change to".

$string = ' https://example.com, https://www.example.com, https://subdomain.example.com ';
$olddomain = ["example.com",'www.'];
$newdomain = ["stackoverflow.com", ''];

$output = str_replace($olddomain, $newdomain, $string);
echo $output;

RESULT

 https://stackoverflow.com, https://stackoverflow.com, https://subdomain.stackoverflow.com