[Resolved] simple query about 'undefined variable'

wendy04

i have this simple php code .. the problem is that with php 4.3.3

i have $subpage as an undefined variable as an error .. im a php beginner .. i realise that subpage needs to be 'defined' but how?
'subpage' is the url prefix for the site pages eg ?subpage = index.php

$path = "path/to/file";
$slash = "/";
$file = ".php";
$page = $path.$slash.$subpage.$file;
if (isset($_GET['subpage'])&& $page && file_exists($page)) {
require($page);
}
elseif (!file_exists($page)) {
include("index".$file);
};
?>

or is there an easier way of doing this .. thanks in advance!

wendy04

oh and can anyone recommend an easy peasy template engine that will work with php 4.3.3 ?

(no smarty .. etc because thats more than i need)

nozom

Could it be that 'register_globals' is off in the PHP ini file I notice in the code that first we have
$subpage
then
$_GET[subpage]

could be the first $subpage needs to be $_GET[subpage]

just a thought,
hugh

swr

Nozom is probably right. If register_globals if off, then $subpage will not be defined. Be sure to read the [man]register_globals[/man] manual page if you haven't before.

You'll probably run into other "undefined variable" warnings, as your error reporting is set high (which is usually a good thing). To avoid the warning, use an @ before the variable. Like this:

echo @$somevariable;

The warnings about undefined variables can be helpful, as if you mistype a variable name PHP will tell you exactly where, because the variable is undefined. So only use @ when you really expect the variable may be undefined; usually only with form variables.

wendy04

thank you for the help.

ill try the changes and the reading!

wendy04

hmm well it works if i add the line

$subpage = $_get[subpage]

before the $page line but does not work if i place the $_get in the $page line as suggested earlier ..

and leave the rest of the code as it is .. but then it gives an undefined error for the above new line .. but with the @ added the error goes and the thing works ..

still not happy about this .. but it works - register globals is off, because it works fine with it on...but thats not the point is it?

anyother suggestions for a cleaner code .. or is this to be expected?

swr

This:

$subpage = $_get[subpage]

Should be this:

$subpage = $_GET['subpage']

Variable names in PHP are case-sensitive, so $_get doesn't work. Also, you need to enclose subpage in quotes, or you'd get another notice about an undefined constant subpage.

You may still need to use the @ though, in case there was no subpage variable on the URL.

wendy04

thanks swr .. for your help.. it seems i can get it to work the way i said before (using the proper case !) but i still need the @ because of the undefined error i still get?!

anyway it works .

ill have to figure out the error later .. thanks again to all.

(ding! ah yes my index page doesnt have a subpage call .. that would resolve that error issue .. as it doesnt appear when the subpage variable is used)

🙂

pdaoust

I realise this is a very old thread, but I thought I'd throw in an answer to a question that never was answered: Smarty http://smarty.php.net is an amazing template engine; I've been using it for a while, and it has a lot of useful features. Beautiful error reporting too; reports the exact line of the error in the template file (just like PHP does for PHP pages).