remove everything except digits

[mikerh9]

I have "string" from form in phone format it can be
[phone] or others. How to remove from the string all characters except digits. So I need
1113243443.

TH

[mrhappiness]

$only_numbers = preg_replace('%[^\\d]%', '', $input);

[xblue]

or, saving a few keystrokes, \D instead of [^\d]

[mikerh9]

What the purpose of %?

[xblue]

just the separator that tells the regex machine where the pattern starts and ends. you can use slashes instead which is more commom, but by no ways required.