Checkboxes and PHP

[dkin]

Hi,

I built an html form with 4 checkboxes and I retrieve their status in PHP script as followed:

$ma=$GET['mtal'];
$my=$GET['mty'];
$mn=$GET['mtn'];
$mf=$GET['mtf'];

If the boxes are pressed I receive the checked value, but if one of the buttons is not pressed I receive an error: e.g. “Notice: Undefined index: mtn in C:\httpd\HTDOCS\show.php on line 38”.

How can I avoid this error?

Thanks

[barand]

Either

• Check if get value is present; if (isset($_GET['xxxx'])) use it.

• Change the error level settings in php.ini to suppress notices.

[planetsim]

when you get an error like that.
I have learnt if a form has been submitted the index is blank therefore not defined

[suntra]

Personnally, what I would do would be this :

$ma = (isset($_GET['mtal'])) ? $_GET['mtal'] : false;
$my = (isset($_GET['mty'])) ? $_GET['mty'] : false;
$mn = (isset($_GET['mtn'])) ? $_GET['mtn'] : false; 
$mf = (isset($_GET['mtf'])) ? $_GET['mtf'] : false;

It simply return the value if it exists, or it returns false if it doesn't.