Remove all characters

[MichaelHe]

Ho do I romove all characters from a string so only 0-9 a-z and A-Z is left.

I found a function called alnum but I'm not sure how to use it.
str_replace can also be used, but then I have to write all the characters I need removed, so I thought that a reversed function existed that removed everything else than alnum.

[rulian]

use str_replace in combination with preg_match and iterate through matches

[MichaelHe]

Yes... but it's a little complicated I think :o)
I have tried many thing. It worked with
$title=str_replace("(","",$title);
$title=str_replace(")","",$title);
$title=str_replace(","," ",$title);
$title=str_replace(" "," ",$title);
and so on... but it's to complicated if all special characters has to be included.

[bradgrafelman]

$string = preg_replace('/[^0-9a-z]/i', '', $string);

For more information on regexp's, you should look at this site. Basically, the pattern says this:

Replace any character that is not 0-9 or a-z, case-insensitive (hence the 'i' modifier at the end), and replace it with an empty string.

[MichaelHe]

Perfect....
Just what I needed... The string has already been made lowercase only like this $title = strtolower($title); so your script will remove everything only leaving the letters and number... and it works 🙂
Thanks alot

[bradgrafelman]

No problem; don't forget to mark this thread resolved.