How to detect when "0" is supplied as a form/$_POST value?

Question

I'm trying to determine whether or not there is a value passed, but the value CAN be 0 ...

isset always returns true, and empty returns false because the value is 0

How can I get around this?

Answer 1

try

bool array_key_exists ( mixed $key , array $array )

like

if (array_key_exists("var1", $_POST)) {
    // positive case, var1 was posted
    if ($_POST["var1"] == 0){
        // var1 was posted and 0
    }else{
        // var1 was posted and is not 0
    }
}

more details are given at the docs.