Help with Syntax?

[PHannum]

Can anyone help me as to what this means?

 

Notice: Undefined index: logged_in in /home/students/phannum/public_html/n413/class/Login/login.inc.php on line 7 Fatal error: Call to undefined function issest() in /home/students/phannum/public_html/n413/class/Login/login.inc.php on line 10

 

Here is my code:

 

<?php
require_once('config.inc.php');
require_once('functions.inc.php');

session_start();

if ($_SESSION['logged_in'] == true) {
	redirect('#');
} else {
	if ((!issest($_POST['username'])) || (!issest($_POST['password'])) OR 
		(!ctype_alnum($_POST['username'])) ) {
		redirect('#');
	}

	$mysql = @new mysql($dbhost, $dbuser, $dbpwd, $dbname);

	if (mysqli_connect_errno()) {
		printf("Unable to connect to database: %s", mysqli_connect_error());
		exit();
	}

	$username = $mysqli->real_escape_string($_POST['username']);
	$password = $mysqli->real_escape_string($_POST['password']);

	$sql = "SELECT * FROM users WHERE username = '" . $username . "' AND password = '" . md5($password) . "'";

	$result = $mysqli->query($sql);

	if(is_object($result) && $result->num_rows == 1) {
		$_SESSION['logged_in'] = true;
		redirect('#');
	} else {
		redirect('#');
	}
}
?>

Thanks!

 

[trq]

Change:

 

if ($_SESSION['logged_in'] == true) {

To:

 

if (isset($_SESSION['logged_in']) && $_SESSION['logged_in'] == true) {

[PHannum]

Thank you for your help!

 

But now it is giving me this error: 

 

Fatal error: Call to undefined function issest() in /home/students/phannum/public_html/n413/class/Login/login.inc.php on line 10

[Psycho]

C'mon man.

 

issest is not the same as isset

[Jacques1]

I think the handling of booleans also needs some practice.

 

What exactly is

if ($some_var == true)

supposed to do?

 

Are you afraid that the variable itself somehow isn't true enough and needs some extra trueness? Then why stop there? Why not:

if (((($some_var == true) == true) == true) == true)

Maybe it's even truer now.

 

Personally, however, I'd simply test the value:

if ($some_var)

[Psycho]

@Jacques1:

I wouldn't beat him up too bad about that - I see it all the time, even by advanced users. But, that is a pet peeve of mine. Even worse is when I see someone use an if/else condition where there is no logic included for the if() condition and only the else condition because the user wasn't able to properly create the condition.