Remove all non-alphanumeric characters in string

[MSRez]

Is there any easy way to remove ALL non-alphanumeric characters in a string regardless of what they are?

I couldn't find a function that does this which is quite surprising.

 

[MSRez]

Ok, turns out there isn't already a function for it but it's simple anyway.

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

Note: retains spaces in the string.