Dear David,
e-Greetings,

Yes, here comes that simple answer:

when the user did not select any item, there won't be any variable named "$prob".
There should be at least one selection; otherwise PHP won't define the array named "$prob".

The solution is to check whether this variable is defined or not?
Here comes a sample PHP code:

<?php
    if (isset($prob)) {
        echo "Selected Items:<br />";

        foreach ($prob as $value) {
            echo "{$value}<br />";
        }
    }
    else {
        echo "User did not select any item.";
    }
?>

Warm regards,
AmirBehzad Eslami

----- Original Message ----- 
  From: David Luo 
  To: www-html@w3.org 
  Sent: Friday, December 19, 2003 10:13 AM
  Subject: Php Checkboxes


  There quite a few checkboxes on my pages 

  x.php 

  If i "check" any of them, it's able to update the tables successfully and add it to the database. I use array names for the checkboxes i.e. 

  <input type="checkbox" name="prob[]" value="hello"> Hello</input>

  However if i dont' select anything, upon hitting Submit, I would expect the array to be null or empty. However any reference i make to prob returns a message saying 

  Undefined variable: prob in /path on line 10

  The checks i have tried so far are 

  if (strcmp($prob[0],"") != 0)

  if($prob != null) 


  How does php deal with no checkbox selection ? There might be a very simple answer to it. 

  Thanks,



  Regards,
  Jerry L
  http://www.brezosoft.com