destroy the value of a variable

[ballhogjoni]

How can I destroy the value of a variable? I tried unset() but all I have to do is refresh the page using the refresh button and the variables are still set.

[HaLo2FrEeEk]

php is a line-by-line serverside language, unlike Javascript which runs on the client machine and so has the ability to update on-the-fly.  You'd need to use post or get variables to modify the code when the page loads.

[ballhogjoni]

If i am not mistaken I do.

 

my code

session_start(); 
include('db.php'); 
include('functions.php'); 
checkLogin('1 2');
$query = mysql_query("SELECT * FROM users WHERE ID = '{$_SESSION['user_id']}'");
$row = mysql_fetch_array($query) or die(mysql_error());
$Username = $row['Username'];
if (!empty($_POST['title'])) {
$title = $_POST['title'];
}
if (!empty($_POST['desc'])) {
$desc = $_POST['desc'];
}
if (!empty($_POST['price'])) {
$price = $_POST['price'];
}
if (isset($title)) {
$title_checked = strip_tags($title);
}
if (isset($desc)) {
$desc_checked = strip_tags($desc);
}
if (isset($title_checked) && isset($desc_checked) && isset($price)) {
if (!empty($title_checked) && !empty($desc_checked) && !empty($price)) {
	if (strlen($title_checked) > 20 || strlen($desc_checked) > 30) {
		$leng = '<span class="problemMessage">Please check the length of your Title and Description. Title is 20 Characters Max and Description is 30 Characters Max.</span>';
	} elseif (strlen($title_checked) <= 20 && strlen($desc_checked) <= 30) {
    		mysql_query("INSERT INTO products (Username, title, description, price) VALUES ('$Username','$title_checked','$desc_checked','$price')") or die(mysql_error());
		$verbage = '<span class="goodMessage">Your product has been saved.</span>';
		unset($title,$desc,$price);
	}
} else {
	$verbage = '<span class="problemMessage">Product has NOT been Saved. Please enable Javascript & be sure to fill in all fields</span>';
	unset($title,$desc,$price);
}
unset($title,$desc,$price);
}
?>

[aim25]

put unset out of the if.

[ballhogjoni]

No I have tried that. It doesn't work.

[btherl]

Please explain in more detail what "It doesn't work" means.

 

As halofreek said, unset() does NOT work across refreshes (the exception being session variables).  If you explain what you want to do, then we can suggest an alternative.

[ballhogjoni]

AW...Thats what I am trying to fix. I am trying to make sure the 'product' is not saved again in the db if someone refreshes the screen. I have written my code to check the db for the 'product' and if it exists it will not add it.

[btherl]

Sounds great!  Checking the db is the best solution.

[ballhogjoni]

Just seeing if there is another solution, as far as unset()