Validating form data

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

I have a mail form with radio buttons and was wondering how can I make sure one button is checked. For all my other text fields I was able to do a check similiar to what I have below and it works great to make sure no blank entries were entered in the mail form. But how would I do a validation check on radio buttons? My radio input data does NOT get validated in my below script area. So I assume radio inputs such as these have a special way of getting validated?


<input name="color" type="radio" value="red"> 
<input name="color" type="radio" value="green"> 
<input name="color" type="radio" value="blue">
[download]

Script part that works with text data:

foreach $field (param) 
{ 
    foreach $value (param($field)) 
    { 
        if ($value eq "") 
        { 
            #blank values ..give user a message here etc..  
        } 
    } 
}
[download]

Comment on Validating form data Select or Download Code

Replies are listed 'Best First'.
Re: Validating form data by dda (Friar) on Sep 23, 2003 at 11:18 UTC
Unchecked radio buttons do not generate 'name=value' pair. So you should check if `param('radiobuttonfieldname')` is defined, using field name known to you. --dda	[reply] [d/l]
Re: Re: Validating form data by Anonymous Monk on Sep 23, 2003 at 15:26 UTC
Thanks that solved my problem!	[reply]
Re: Validating form data by Theo (Priest) on Sep 23, 2003 at 23:42 UTC
This may be completely inappropriate for your situation, but you can force one of the buttons to be selected by default. `<input name="color" type="radio" value="red"> <input name="color" type="radio" value="green"> <input name="color" type="radio" value="blue" checked>` [download] This sets Blue as the default value. The downside may be that If the user doesn't notice, the wrong color may be indicated The user cannot unselect a value for that button This is often a bad idea, but occasionally useful. -theo- (so many nodes and so little time ... ) Note: All opinions are untested, unless otherwise stated	[reply] [d/l]