Error when looping over list

Question

Looping over a series of lists created from form fields
generates an error when one of the fields on the form has been left
blank. The form is a list of event dates, start times and end
times. One event can have a number of times.
When the end time is uncertain, we want to leave it blank.
However, doing so shortens the list created from #form.endtime# so
that the lists don't match and there's an error message:
"Invalid list index 2.
In function ListGetAt(list, index [, delimiters]), the value
of index, 2, is not a valid as the first argument (this list has 1
elements). Valid indexes are in the range 1 through the number of
elements in the list."
How do you get around this problem? Tx.

Answer 1

yoman,
No need for separate forms. Use a counter to number each
group of field names
<input name="EventDateID1" ...>
<input name="EventDate1" ...>
<input name="EventDateID2" ...>
<input name="EventDate2" ...>
Then loop through the form fields on your action page
<cfloop from="1" to="#form.maxCounter#"
index="counter">
<cfset EventDateID = form["EventDateID#counter#">
<cfset EventDate = form["EventDate#counter#">
... rest of fields
<cfquery name="UpdateFeatures" datasource="#dsn#">
UPDATE EventDates
SET EventDate = '#EventDate#', ....
WHERE EventDateID = #EventDateID#
</cfquery>
</cfloop>
You should validate the values and/or use cfqueryparam