[liphp] explode problem

[Venkatagiriyappa, Veena]

Hi,
I need to verify if all the data in a html form (user input) is complete or
not. If the data is incomplete, the status will have to be set as
incomplete. So, I have a variable which holds all the fields from the html
form. Later I use explode function and send it to a foreach loop to check
for the empty filed.
PHP:
<?php
$required =
"title,sample,sourceorganism,expressionsystem,molecularweight,sequence,signi
ficance,relevant,requirements,anomalousatom,biologicalhazard,hazards";

        $fields_required = explode(",", $required);

?>


but I see that the explode function doesn't take more than 10 fields.
I have disabled the register_globals in the php.ini for security reasons.
Then, what is the alternate way of checking the fields for completeness?