[ic] Interchange demo: userdb mail_list field cannot be set to empty

[David Christensen]

On Nov 5, 2009, at 11:49 AM, Mike Heins wrote:

> Quoting Stefan Hornburg (Racke) (racke at linuxia.de):
>> Ton Verhagen wrote:
>>>
>>> Quoting Mike Heins wrote:
>>>
>>>> Quoting Ton Verhagen (ton at verhagen.net):
>>>>>
>>>>> Ton Verhagen wrote:
>>>>>
>>>>>> Dear IC'ers,
>>>>>>
>>>>>> In the current demo on www.icdevgroup.org it is not possible to  
>>>>>> set
>>>>>> the userdb field mail_list to an empty value.
>>>>>> In other words, users are not able to unsubscribe from all  
>>>>>> mailing
>>>>>> lists. The last value always remains active.
>>>>>>
>>>>>> The demo uses a multiple select box for this feature. I have also
>>>>>> tried checkboxes with no avail.
>>>>>>
>>>>>> Any ideas?
>>>>>
>>>>>
>>>>> Apparently an empty cgi variable does not overwrite an existing  
>>>>> value
>>>>> variable.
>>>>>
>>>>
>>>> This is not true at all.
>>>>
>>>> You can test it yourself:
>>>>
>>>>
>>>> http://demo.icdevgroup.org/i/demo1/ord/checkout?fname=ton&mv_action=refresh
>>>>
>>>>
>>>> That will show your name. Now do:
>>>>
>>>>
>>>> http://demo.icdevgroup.org/i/demo1/ord/checkout?fname=&mv_action=refresh
>>>
>>>
>>> You might be right in this regard.
>>>
>>> But please try similar things with check boxes and/or multiple  
>>> selects:
>>> an empty selection (no checkboxes ticked) won't overwrite an  
>>> existing
>>> value in the session.
>>>
>>
>> Yeah, but the better solution is probably do set the mail_list  
>> value inside
>> "Save_database" scratch.
>
> Yes, or something. You could do:
>
> 	[calc]
> 	    $Values->{mail_list} ||= 'none';
> 	    return;
> 	[/calc]


Wouldn't an empty hidden with the same name work in that regard?  If  
checkboxes are not checked, they are not included in the CGI params,  
so they cannot be unset in that fashion; an empty hidden would provide  
the 'name=' that you need, although some filter may be needed to strip  
the \0 from the value when a "real" value is included.

Regards,

David
--
David Christensen
End Point Corporation
david at endpoint.com