Variable default question

Ramsobot

Hi, there, I have a fairly basic question. I have a php template page which cycles through images and what I want is a default picture to be displayed if there's no ID in the address.

Here's what I have, but it isn't working just right. It works if you have just the basic page, but as soon as you add an ID variable it displays an error. Any ideas?

<? 

if (!$ID){ 
        $ID = 1; 
} 

?>

rebelo

What's the error being displayed? I am not really too clear on what your problem is, but it sounds like you're passing the ID value as a GET value, right? Like:

mypage.com/index.php?ID=3

If that's the case, the appropriate way to write it would be:

<?php
if (isset($_GET['ID'])) {
    $template = $_GET['ID'];
} else {
    $template = 1;
}
?>

And then use $template instead of $ID (or whatever you want). Superglobals are teh evul.

Ramsobot

That did it! Thanks so much.

swr

This is such a common thing that I usually create a function for it:

function getvar($var, $default = '') {
    if (isset($_REQUEST[$var])) {
        return $_REQUEST[$var];
    }
    else {
        return $default;
    }
}

Then you can use getvar('ID', 1).

The function can also be modified to do addslashes/stripslashes or whatever other stuff you need (in case you ever need to run the code under a server with different configuration settings).