undefined variable err. PHP4/IIS/Win2k

[Anon]

I have php up and running under IIS on Win2k and while most things work (includes, echo(), Env. vars, etc.) the installation has a specific problem when i try to use variables. For some reason for every variable that I use: ie.

if ($some_var) { do this }

I get the error:

Warning: Undefined variable: some_var in ... (etc.)

Am i missing some IIS setting or is it something else completely?

//Tcl

[Anon]

You probable use the instalation program of php, put in error level Display All errors...
without notices and warnings! =)

[[deleted]]

It's something else completely.

The error you get means exactly what it says:
The variable was not 'defined' which means it did not get any value assigned to it before it got to this particular line in the script.

A var that did not have a value assigned to it can theoretically take ANY value.
That means that you should NOT trust the outcome of your IF statement.

Allways check if a var is set before you use it for the first time:

if (isset($var))
{
// Variable has been used before, it's safe to use
if ($var == 2)
{
// do something
};
}
else
{
// The var has not been used before!
$var = 1;
};

[Anon]

Thanks both, it was indeed the error settings that did the trick. The code is pretty clean, mostly prebuilt stuff from the phpwebsite CMS, the variables are all checked first.

//Tcl

[Anon]

I had this problem with all predefined variables in PHP 4.2.0 and found out it's because the way PHP handles these was changed in version 4.1. In order to be able to reference predefined variables such as $HTTP_HOST in 4.1 or higher, you need to turn the register_globals=On in the PHP.ini. Reference this page: http://www.php.net/manual/en/language.variables.predefined.php

[Anon]

Thank you! I followed the most basic of tutorials on PHP and forms and could not get ANYTHING to work!

Shouldn't this be made a little clearer for beginners, like being put in the FAQ on the php site or something?????!?!!