PHP-如何获取函数传递的变量名和数组键

Question

Array with keys:

$foo = array('id' => '123');

When I call this function:

printVarNameAndKey($foo['id']);

Print out:

$foo['id']

Is this possible in PHP?

EDIT

This code does not work:

function print_var_name($var) {
    foreach($GLOBALS as $var_name => $value) {
        if ($value === $var) {
            return $var_name;
        }
    }

    return false;
}

Answer 1

$GLOBALS is not a super-global, you may update your code to look like

function print_var_name($var) {
    global $GLOBALS;
    foreach($GLOBALS as $var_name => $value) {
        if ($value === $var) {
            return $var_name;
        }
    }

    return false;
}

but as @jeroen said, a value does not uniquely identify a variable.