Please help! How can I validate Radio Buttons and List Menu with PHP.

Question

Hello everyone, I have been learning PHP step by step and
making little projects.
The point is I find it easy to learn by doing "practical
projects."
I have been reading the David Powers's Book on PHP Solutions
and it's really great, however there is nothing mentioned regarding
Validating Radio buttons. I know the book cannot cover every aspect
of PHP and maybe someone in here can help.
I have been learning how to process HTML forms with PHP.
The problem is every book or tutorial I have read or
encountered fall short on validation.
I'm wondering how I can learn to validate Radio Buttons and
Select List Menu.
I have managed to create validation for all other fields but
have no clue as to how I can get validation for Radio Buttons and
List Menu.
I would also like an error message echoed when the user does
not click a button or make a selection and try to submit the form.
I would appreciate any help.
Patrick

Answer 1

It's not that default value is "None." In fact it's not. It
will only be
"none" when the form is submitted.
Also if your submit button is names 'send' then
$_POST['send'] will only be
set if the form was submitted.
Make sure you didn't hit the refresh button on your browser
which usually
reposts the information. Also make sure you did not reach the
form from
another form with the same button names.
Otherwise paste the snippet.
Also you can check what fields are set in the post array by
adding this to
the top of (or anywhere on) your page:
print_r($_POST);
Cosmo
"Webethics" <[email protected]> wrote in
message
news:[email protected]...
>
quote:
Originally posted by:
Newsgroup User
> Off the top of my head this should be no different than
your radio buttons
> except that 'productSelection' will always fail the
!isset check when the
> form is submitted since the default value is "None", and
therefore always
> set. :-)
>
> So how about this..?
> <?php
> if (isset($_POST['send']) and
($_POST['productSelection'] == "None"))
> {echo "Please select a product.";}
> ?>
>
>
>
>
> "Webethics" <[email protected]> wrote
in message
> news:[email protected]...
> > Another question - how do i applied the code you
just showed me to
> > select
> > menu
> > or select list?
> >
> > This is the list:
> >
> > <div class="problemProduct">
> > <label for="productSelection"><span
class="product_label">Product
> > Name.</span></label>
> > <select name="productSelection" id="products"
class="selection">
> > <option value="None">-------------Select a
product----------</option>
> > <option value="Everex DVD Burner">Everex DVD
Burner</option>
> > <option value="Vidia DVD Burner">Vidia DVD
Burner</option>
> > <option value="Excerion Super Drive">Excerion
Super Drive</option>
> > <option value="Maxille Optical Multi
Burner">Maxille Optical Multi
> > Burner</option>
> > <option value="Pavilion HD Drives">Pavilion
HD Drives</option>
> > </select>
> > </div>
> >
> > I thought I could just change the name is the code
from operatingSystem
> > to
> > productSelection.
> >
> > Something like this:
> >
> > From this:
> >
> > <?php
> > if (isset($_POST[send]) and
!isset($_POST['operatingSystem']))
> > {echo "Please select an operating system.";}
> > ?>
> >
> > To this:
> >
> > <?php
> > if (isset($_POST[send]) and
!isset($_POST['productSelection']))
> > {echo "Please select an operating system.";}
> > ?>
> >
> > But this does not work, any ideas?
> >
> > Patrick
> >
>
>
>
>
> Hey, I tried this about but as you mentioned, since the
default product
> value
> is "None" an error message appears when the page loads.
>
> Is there a way to code this things so that even though
the default value
> is
> "None" there ia no error message untle you hit the
submit?
>
> When I applied the code, it messes up the previous code,
now the operating
> system is requiring an entry on page load.
>
> When I remove the code from the list menu everything
goes back to normal.
>
> I know this is a little much but I have no other
alternatives.
>
> Patrick
>