[whatwg] [wf2] Filtering datalist with pattern

[Henri Sivonen]

On May 26, 2006, at 09:23, Matthew Raymond wrote:

> Henri Sivonen wrote:
>> The WF2 spec does not say anything about filtering autocomplete lists
>> on pattern and Opera 9 does not do it. However, autocomplete entries
>> that would fail form validation are not particularly useful.
>>
>> I suggest saying that potential autocomplete items (whether supplied
>> by the UA itself or read from a datalist) should be tested against
>> the datatype and the pattern of the form field being filled and
>> should only be shown if they match both the datatype and the pattern.
>
>    This assumes that the inclusion of such items is unintentional.

When the values are supplied by the UA (e.g. IRIs from the browsing  
history), the inclusion of non-matching items certainly is  
unintentional from the author's point of view.

> What
> if you wanted the user to be able to select from a fixed set of values
> that fall outside of the pattern in addition to those that fit the
> pattern?

Then you'd need to change the form validation phase in the spec.

> Is the proper way to handle this to force web authors to write
> these values into the pattern?

Yes. (Of course, alternatively, they can remove the pattern and  
constrain the field by scripting.)

-- 
Henri Sivonen
hsivonen at iki.fi
http://hsivonen.iki.fi/