[SOLVED] if statement not executing

[soycharliente]

Neither of these bits of code are working for me.

1:

<?php
if ($loggedin) {
echo "<td><a href=\"showThread.php?id=$id\" title=\"$title\">$title</a></td>";
} else {
echo "<td>$title</td>";
}
?>

 

2:

<?php
echo ($loggedin) ? "<td><a href=\"showThread.php?id=$id\" title=\"$title\">$title</a></td>" : "<td>$title</td>";
?>

 

I'm trying to get the link part of the if/ternary to display if you're logged in. I know for a fact that I am logged in because the login link has changed to a logout link.

 

Some code on each page to check for status:

<?php
if (empty($_SESSION["user"])) {
$loggedin = FALSE;
} else {
$loggedin = TRUE;
}
?>

 

And the login script that creates that session variable:

<?php
$loggedIn = FALSE;
if(isset($_POST["submit_login"])) {
$un =     $_POST["un"];
$pw = md5($_POST["pw"]);
dbconnect();
$query = "SELECT * FROM blog_users WHERE username='$un' AND password='$pw'";
$result = mysql_query($query) or DIE("Error: LOGIN. Contact Webmaster.");
if (mysql_num_rows($result) > 0) {
	$r = mysql_fetch_assoc($result);
	$user = $r["username"];
	$pass = $r["password"];
	if ($un == $user && $pw == $pass) {
		$_SESSION["user"] = $un;
		$loggedIn = TRUE;
		$loginError = FALSE;
		header("Location: index.php");
		exit;
	}
	$loginError = TRUE;
} else {
	$loginError = TRUE;
}
dbclose();
}
?>

[Yesideez]

Instead of checking the variable $loggedin check a session variable instead as the contents of $loggedin will be lost when you access a new script.

[soycharliente]

Bang-a-rang. Thanks.

 

Could I make $loggedin a global variable? Would that let it been used everywhere? If so, how do I do that? Register globals is on.

[soycharliente]

Now the links still render when I logout.

<?php
if (isset($_GET["logout"])) {
session_destroy();
$loggedin = FALSE;
}
?>

 

The URL:

http://www.meh.com/xxx/xxx/index.php?logout (not real)

[Yesideez]

Globals = very scary.

 

Best keep them local and declare them global only when needed!!!

[roopurt18]

Could I make $loggedin a global variable? Would that let it been used everywhere? If so, how do I do that? Register globals is on.

 

You certainly could, but I recommend not doing so.  Avoid globals like the plague.

 

Instead, why not create a class or interface with functions like isLoggedIn(), logout, etc. that check / edit what's in $_SESSION?

 

Then in your site you can just say:

<?php
  if(MySession::isLoggedIn()){
    echo "You are logged in.";
  }else{
    echo "You are not logged in.";
  }
?>

 

Many newer programmers ask what the point of using classes or objects is; well this is one of them.  If you later decide to change how the site tracks logged in users, you only edit your functions MySession::isLoggedIn(), etc. and the rest of the site continues to work.  In other words, if you have to change implementation details later, as long as you keep the interface (in this case, MySession) the same, you don't have to modify code elsewhere.

[Yesideez]

roopurt, do you know of any links I can read up on the :: operator?

 

I've never seen that. My classes use -> instead!

[soycharliente]

I have no idea how to write classes, so that's a new thing to me.

 

Until then, I just wrote separate functions with different lines at the line in question.

[Yesideez]

Charlie, classes are awesome. I've built a small library of special functions I've written.

 

Instead of copying and pastign code all the time you just upload a class and use it. It's great for hiding code as well and they're extremely versatile.

[roopurt18]

The :: operator allows you to access a class method statically, i.e. without an instance of the class.

 

<?php
class Foo{
  function hello(){
    echo "Hello, World!";
  }
}

// Access the function without an instance of the class:
Foo::hello();
?>

 

Keep in mind that the $this variable only exists within instances of a class.

 

(EDIT) In this sense, you can fake name spaces in PHP.