note 29020 deleted from function.eval by victor
| From: | victor@php.net | Date: | Sat, 12 Jun 2004 22:35:58 +0000 |
| Subject: | note 29020 deleted from function.eval by victor | ||
| References: | 1 | Groups: | php.notes |
| Request: | Send a blank email to php-notes+get-70993@lists.php.net to get a copy of this message | ||
Note Submitter: Taras Young
----
A quick and simple (and hopefully safe) method of evaluating sums:
function evalsum($sum){
// Sum may only contain the following characters:
$check = strtr($sum, "0123456789+-*/()", " ");
if ( trim($check) == "" ) {
$to_eval="\$evalled=" . $sum . ";";
eval($to_eval);
}else{
$evalled = "Evaluation error";
}
return $evalled;
}
echo evalsum("2+2");
Unfortunately, since PHP uses pow(a,b) for powers rather than a^b, this won't do powers.