stripping variables down to alphanumerics

[michaelk]

What would be the easiest way to strip a string down to just alphanumerics - no spaces... (for a username / password database).

Currently, i use ereg_replace(); to remove the whitespace. Is there a built in function or 'easier' way to check for / remove all other characters in a string without doing a search and replace for each one seperately ?

Thanks !

[diego25]

I'd use preg_replace, but it's the same idea as ereg_replace...so no, there's no easier way.

Diego

[WinterDragon]

Maybe Preg? This will replace all ALPHA characters, A-Z, upper and lowercase...

$pattern = "/[A-Za-z/g";
$replace = "";
$string = "Just some test... 45 test 455";
$string = preg_replace($pattern, $replace, $string);
echo $string;

[WinterDragon]

HOLD ON! Messed up... hehe the pattern should be...

/[A-Za-z]/

DROP THAT g at the end. 🙂

[michaelk]

thanks!

convienent for removing all alpha characters, but i want to <B>keep</B> only alpha characters and remove all others....

[xblue]

you can negate a character class (that definition in square brackets) by inserting ^ at the beginning, like

// strip off everthing that is not listed within the brackets
$str = preg_replace('/[^a-zA-Z0-9]/', '', $str);

[edit: typo]

[michaelk]

thanks so much !
i knew there had to be an easier way, there's a reason i've chosen to learn php rather than another language. 😉