[RESOLVED] Return FALSE or !$... in PHP?

kilbey1

I have a class that sets a return to false if there is an error:

				$delete = $database->select($sql);
				if (!$delete) {
					$database->print_last_error(false);
					$database->print_last_query();
					return false;
					exit;
...

When I process that form, I want it to go back to the referring page if there is an error; otherwise, go to the main page.

			$data = $newsHandler->deleteArticle($id);

		$_SESSION['value_array'] = $_POST;
    	$_SESSION['error_array'] = $newsHandler->error;
		if($data == false) {
			//header("Location: main.php");				
			header("Location: ".$session->referrer."");
			exit;
		} else {
			header("Location: main.php");
			exit;
		}

However, when I check for $data == false, it doesn't detect as false. When I try !$data, I believe the same thing happens. What should I be using to determine if the update to the database works or not? I thought if I returned false, then I could check for false.

dagon

var_dump($data); check what it is really returning.

kilbey1

on an add...

array(4) { ["id"]=>  string(4) "Null" ["text"]=>  string(31) "<p>rahrahrahrah</p>" ["created_dtm"]=>  string(19) "2007-05-25 17:20:14" ["display_date"]=>  int(1180128014) }

on a delete...

array(1) { ["id"]=>  string(2) "55" }

So assuming that isn't false, I'd expect the following to take me to main.php:

if($data == false) {		
				header("Location: ".$session->referrer."");
				exit;
			} else {
				header("Location: main.php");
				exit;
			}

But it instead takes me to header("Location: ".$session->referrer."");.

bradgrafelman

Try using a strict comparison with '==='.

kilbey1

Yes! That worked!

Can you point me to some info as to why this is the case?

bradgrafelman

Eh... I'm not entirely sure where to point you. All I know is that it appeared as though $data had some valid data in it, but it was still evaluated as false (loosely). Since you have an error funtion that returns a specific value (boolean FALSE... not 0, or NULL, or '0', etc.), checking for a boolean FALSE and nothing else seemed to be the logical (no pun intended 😉) solution.

jmack159

http://us.php.net/manual/en/language.operators.comparison.php