Evaluating Expression Held in String

[Anon]

I have an expression held in a string, for example:

$expr = "1 && 0"

[NB: The expression will always evaluate to either 0 or 1]

How do I actually evaluate this in an if construct? Saying:

if ($expr){
echo "x";
}else {
echo "y";
}

doesn't work. Any ideas?

Cheers

Paul

[van__]

From what you've been posting, it looks like you are trying to convert some logical expressions thru PHP.

I am illogical, so I don't have the faintest on this last one. Other than what you are describing sounds like a job for the eval function.

This evaluates to false:

<?
$str = "1 && 0";
eval("\$str = " . $str . ";");
if ($str) {
echo "x";
} else {
echo "y";
}
?>

[van__]

Looks like it works.

this evaluates to true:

<?
$str = "0 || 1";
eval("\$str = " . $str . ";");
if ($str) {
echo "x";
} else {
echo "y";
}
?>