Replace all characters except letters, numbers, spaces and underscores

Question

I am looking to replace all characters in a string except letters, numbers, spaces and underscores.

Could someone please provide a example?

Solution 1

I normally use something like:

$string = preg_replace("/[^ \w]+/", "", $string);

That replaces all non-space and non-word characters with nothing.

Solution 2

[^0-9a-zA-Z_\s] 

is what you want to replace.

Solution 3

<?php
$string = 'April 15, 2003';
$pattern = '/[^\w ]+/';
$replacement = '';
echo preg_replace($pattern, $replacement, $string);
?>

Comments

[TecBrat]

This one helped me on a similar issue. Thanks! (For others reading this, don't forget to wrap it in slashes like this: $new_string=preg_replace('/[^0-9a-zA-Z_]/',"",$old_string) I took out the \s because I didn't need to allow spaces.

[DarkMukke]

you should use single quotes for regex in PHP preg_replace('/[^ \w]+/', '', $string) double quotes with \ in them can result in unexpected behaviour

[Vishal Kumar Sahu]

\s does not mean space always...

[Eugene]

you should say all non-english characters, for example it removes Cyrillic symbols too