Wrong encoding or wrong regular expression? How to fix?

Question

Yii

I get the data using the GET method

$request = Yii::$app->request;
 $message = $request->get('message');

Further processing takes place using the preg_replace function:

$code = preg_replace ("/[^0-9\s]/","",$message);
$triger = preg_replace ("/[^a-zA-ZА-Яа-я\s]/","",$message);

and when you try to use it, the following signs appear:

click

Try text:

STOP KITCHEN

MK 1938

MK is displayed adequately, but nothing sensible comes out with the first sentence.
If possible, please explain what I'm doing wrong.

Answer 1

Good morning.
Encoding.
Check encoding matches everywhere, convert everything to utf-8.
Also add the "u" modifier to the regular expression.

$triger = preg_replace ("/[^a-zA-ZА-Яа-я\s]/u","",$message);