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

[Ton Verhagen]

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.

Best,

Ton