asked on

OnChange Event for DropDown List

I am having a problem... I have an access database and an ASP application. On my add screen I am populating a dropdown box with a field from the database. I want to use the OnChange event to fill in a textbox below with the corresponding information. I am combining HTML, ASP, and VBScript for my Onchange event.

I believe the easiest way to achieve this is to create an array. I receive two JS Errors when I run this page
the first error is expected end (this occurs at the end of this line: var pubArray = new Array()

Then I get this error object undefined. (this occurs at this line: <option></option>)

Below is my code! Can somebody please help? I have lost hours on this and I would really appreciate any input.
--------------------------------------------------------------------------------

objRS.Open "tblJournalNames", objDC, 0, 1

If Not objRS.EOF Then
objRS.MoveFirst
%>

<script type="text/vbscript" language="vbscript">
var pubArray = new Array()

function applytoLabel(a)
document.Form1.txtJournal.value = a.value
document.Form1.txtAuthor.Value = pubArray(a.SelectedIndex)
end function
</script>
<select name="comboJournal" onChange="applytoLabel(this)">
<option></option>
<%
x = 0
Do While Not objRS.EOF
%>
<script language="vbscript">
pubArray<%= x %> = "<%= objRs.Fields("Pub_Code").Value %>"
</script>
<option value="<%= objRS.Fields("Journal_Name") %>"><%= objRS.Fields("Journal_Name") %></option>
<%
objRS.MoveNext
Loop
%>
</select>
<font face="Tahoma">
<% end if %>

grantrj

Hi,
I may be missing the point but instead of <option></option> could you have <option value=-1></option>?
This should hopefully ensure that the object is defined as I beleive that an option object is defined if it has a value....

Hope this helps

JCWright30

ASKER

Here is the fix. This works well and I wanted to post if for others having similar problems.

objRS.Open "tblJournalNames", objDC, 0, 1

If Not objRS.EOF Then
objRS.MoveFirst
%>

<script type="text/vbscript" language="vbscript">
dim pubArray()

function applytoLabel(a)
if a.SelectedIndex = 0 then
document.Form1.txtJournal.value = ""
document.Form1.txtAuthor.Value = ""
else
document.Form1.txtJournal.value = a.value
document.Form1.txtAuthor.Value = pubArray(a.SelectedIndex - 1)
end if
end function</script>
<select name="comboJournal" onChange="applytoLabel(this)">
<option></option>
<%
x = 0
Do While Not objRS.EOF
%>
<script language="vbscript">
ReDim Preserve pubArray(<%= x %>)
pubArray(<%= x %>) = "<%= objRs.Fields("Pub_Code").Value %>"
</script>
<option value="<%= objRS.Fields("Journal_Name") %>"><%= objRS.Fields("Journal_Name") %></option>
<%
x = x + 1
objRS.MoveNext
Loop
%>
</select>
<font face="Tahoma">
<% end if %>

ASKER CERTIFIED SOLUTION

modulo

membership

This solution is only available to members.

To access this solution, you must be a member of Experts Exchange.

Start Free Trial