Preforming math stored in variables

Question

I have 3 variables like this: $first = 2; $second = 5; $operation = \'*\';

how can I programaticly assign the solution to this math problem to the $answer variable? I ha

Answer 1

It works fine for me:

var_dump(eval("return $first $operator $second;"));

But eval is evil. You should better use a function like this:

function foobar($operator)
{
    $args = func_get_args();
    array_shift($args);
    switch ($operator) {
    case "*":
        if (count($args) < 1) {
            return false;
        }
        $result = array_shift($args) * array_shift($args);
        break;
    /*
        …
    */
    }
    if (count($args)) {
        return call_user_func_array(__FUNCTION__, array_merge(array($operator, $result), $args));
    }
    return $result;
}
var_dump(foobar("*", 3, 5, 7));