On Sunday, June 23, 2002, at 09:30  PM, Vicki wrote:

> If you can suggest code that works, that would be great, or at least
> point me in the right direction if I'm on the wrong track with
> checkboxes. If you haven't noticed already, I'm very, very new to PHP
> and haven't quite got the hang of it yet. :=)

Someone else mentioned the "empty()" language construct.  Learn this and 
use it everywhere.  I find that it is probably one of my most-often used 
tricks to evaluate user input of any kind, especially checkboxes and 
radio buttons.  The reason why is because if you use "if 
($_POST['varname'])" or "if (isset($_POST['varname']))", you're testing 
to see if the variable was ever set.  With HTML forms, they may in fact 
have been set but have no values.  Using empty() will test to see if 
they evaluate to false (such as if they contain an empty string, which 
is what happens when someone submits a form but doesn't actually put 
some data into a certain input), and that is a reliable way to test for 

Also, I have a shopping-cart-like feature on my site.  I store my 
"purchased" objects in an array.  One thing that I learned the hard way 
is that if you use unset() to remove items from this array, you will end 
up with empty array elements.  If you need to re-order the array (to put 
the indexes into a sequential order once again), you can do something 
like this:

array_push($array, 'dummy_value');

Because using array_pop() will re-index the array.  Much thanks to 
Nathan for that tip.



Erik Price
Web Developer Temp
Media Lab, H.H. Brown

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