Client side and server side scripting problem

K

Kathryn

Hiya
I have a problem with using some client side and server side scripting
together in an ASP. I'm using VBScript.

What I'm trying to achieve is this -

- Page loads up and some server side vbscript reads the database and
populates a listbox on the page with the first field from each record
in the recordset. This works fine.
- User selects an option on the listbox and, using the OnChange, I
call a client side vbscript function. This function needs to populate
the text fields on the page with the rest of the fields from the
relevant record in the recordset in the server side script that was
done when the page loaded up.

I realise that mixing server side and client side isn't possible but
I'm looking for a way around this. What I can do is create an array in
the server side code from the recordset and then pass this array into
the function. I'm having trouble getting this to work though. The
problem is that it doesn't seem to want to populate the text fields.
It goes into the function alright because if I put an alert in there
it appears when I select something from the list box.

Here's some snippets from my code

The server side script

<%'Set up and open the connection to the database
dim conn, rs, StructureArray(10,10)
set conn=Server.CreateObject("ADODB.Connection")
conn.provider="Microsoft.Jet.OLEDB.4.0"
conn.open(server.mappath("structures.mdb"))

set rs = Server.CreateObject ("ADODB.recordset")
rs.Open "SELECT * FROM RunStructureValues WHERE WorkspaceID = '12',
conn

for intRow = 1 to StructureNameRS.RecordCount
StructureArray(intRow,1) = StructureNameRS.Fields("RunNumber")
StructureArray(intRow,2) = StructureNameRS.Fields("MPFLoc")
StructureArray(intRow,3) = StructureNameRS.Fields("MPFExt")
intRow = intRow + 1
next
%>

The client side script

<script language="VBScript">
function UpdateFields(StructureArray)
dim index
index = form1.RunStructureName.selectedIndex
form1.RunNumber.value = StructureArray(index,1)
form1.MPFLoc.value = StructureArray(index,2)
form1.MPFExt.value = StructureArray(index,3)
end function
</script>

The form

<form method="post" action="action.asp" target="_self" name="form1">
<table>
<tr>
<td class="SubHeader">Run Structure</td>
<td>
<SELECT name="RunStructureName"
onchange="UpdateFields(<%=StructureArray%>)">
<%
do until StructureNameRS.EOF%>
<OPTION><%=StructureNameRS.Fields("RunStructureName")%></OPTION>
<%
StructureNameRS.MoveNext
loop
%>
</SELECT>
</td>
</tr>
<tr>
<td class="SubHeader">Run Number</td>
<td><input type="text" name="RunNumber" value=""></td>
</tr>
<tr>
<td class="SubHeader">Model Point File Location</td>
<td><input type="text" name="MPFLoc" value=""></td>
</tr>
<tr>
<td class="SubHeader">Model Point File Extension</td>
<td><input type="text" name="MPFExt" value=""></td>
</tr> </table>
</form>
Any advice would be greatly appreciated as my deadline is looming and
this is the one thing I'm having trouble with! If there is a better
way to do this sort of thing then please let me know also!

Thanks.
Kathryn.
 
T

Tom Kaminski [MVP]

Kathryn said:
Hiya
I have a problem with using some client side and server side scripting
together in an ASP. I'm using VBScript.

What I'm trying to achieve is this -

- Page loads up and some server side vbscript reads the database and
populates a listbox on the page with the first field from each record
in the recordset. This works fine.
- User selects an option on the listbox and, using the OnChange, I
call a client side vbscript function. This function needs to populate
the text fields on the page with the rest of the fields from the
relevant record in the recordset in the server side script that was
done when the page loaded up.

I realise that mixing server side and client side isn't possible but
I'm looking for a way around this. What I can do is create an array in
the server side code from the recordset and then pass this array into
the function. I'm having trouble getting this to work though. The
problem is that it doesn't seem to want to populate the text fields.
It goes into the function alright because if I put an alert in there
it appears when I select something from the list box.

Here's some snippets from my code

The server side script

<%'Set up and open the connection to the database
dim conn, rs, StructureArray(10,10)
set conn=Server.CreateObject("ADODB.Connection")
conn.provider="Microsoft.Jet.OLEDB.4.0"
conn.open(server.mappath("structures.mdb"))

set rs = Server.CreateObject ("ADODB.recordset")
rs.Open "SELECT * FROM RunStructureValues WHERE WorkspaceID = '12',
conn

for intRow = 1 to StructureNameRS.RecordCount
StructureArray(intRow,1) = StructureNameRS.Fields("RunNumber")
StructureArray(intRow,2) = StructureNameRS.Fields("MPFLoc")
StructureArray(intRow,3) = StructureNameRS.Fields("MPFExt")
intRow = intRow + 1
next
%>

The client side script

<script language="VBScript">
function UpdateFields(StructureArray)
dim index
index = form1.RunStructureName.selectedIndex
form1.RunNumber.value = StructureArray(index,1)
form1.MPFLoc.value = StructureArray(index,2)
form1.MPFExt.value = StructureArray(index,3)
end function
</script>

The form

<form method="post" action="action.asp" target="_self" name="form1">
<table>
<tr>
<td class="SubHeader">Run Structure</td>
<td>
<SELECT name="RunStructureName"
onchange="UpdateFields(<%=StructureArray%>)">
<%
do until StructureNameRS.EOF%>
<OPTION><%=StructureNameRS.Fields("RunStructureName")%></OPTION>
<%
StructureNameRS.MoveNext
loop
%>
</SELECT>
</td>
</tr>
<tr>
<td class="SubHeader">Run Number</td>
<td><input type="text" name="RunNumber" value=""></td>
</tr>
<tr>
<td class="SubHeader">Model Point File Location</td>
<td><input type="text" name="MPFLoc" value=""></td>
</tr>
<tr>
<td class="SubHeader">Model Point File Extension</td>
<td><input type="text" name="MPFExt" value=""></td>
</tr> </table>
</form>
Any advice would be greatly appreciated as my deadline is looming and
this is the one thing I'm having trouble with! If there is a better
way to do this sort of thing then please let me know also!

When building the array, you need to have the server script use
Response.Write to write out the client script that will build it. In your
snippet you are only establishing the array on the server side. Something
like:

Response.Write "<script>" & vbcrlf
for intRow = 1 to StructureNameRS.RecordCount
Response.Write "StructureArray(intRow,1) = " &
StructureNameRS.Fields("RunNumber") & vbcrlf
etc ...
 
W

WIlliam Morris

Hello Kathryn,

You are correct: you can't mix server side and client side, but you're
heading in more or less the right direction. Your client-side script has no
idea what StructureArray is, so what you need to do is write the array to
the client, and access it from there. Something like (borrowing your own
code...hand me that pencil, won't you? Thanks...):

<%
for intRow = 1 to StructureNameRS.RecordCount
StructureArray(intRow,1) = StructureNameRS.Fields("RunNumber")
StructureArray(intRow,2) = StructureNameRS.Fields("MPFLoc")
StructureArray(intRow,3) = StructureNameRS.Fields("MPFExt")
intRow = intRow + 1
next
'--- so now you've got this server side array
'--- another, possibly easier way, though you have to make your SELECT
explicit;
'--- for a variety of reasons, you shouldn't use SELECT * anyway
'--- because the array is actually going to end up on the client side, this
step might or might not be necessary,
'--- but I'd do it because I want to know my array bounds in advance.
Looping an array is faster
'--- than looping a recordset, too.
StructureArray = StructureNameRS.GetRows()
Dim rCounter, cCounter
'--- now the client side magic
With Response
.Write "<" & "script language=""VBScript"" type=""text/vbscript"">" &
vbCrLf
.Write " Dim ClientSideArray" & vbCrLf
.Write " Redim ClientSideArray(" & UBound(StructureArray) & "," &
UBound(StructureArray, 2) & ")" & vbCrLf
For rCounter = 0 to Ubound(StructureArray, 2)
For cCounter = 0 to Ubound(StructureArray)
.Write " ClientSideArray(" & rCounter & "," & cCounter & ")
= """ & StructureArray(rCounter, cCounter) & """" & vbCrLf
Next
Next
.Write "<" & "/script>" & vbCrLf
End With
'--- now you've got a client side array you can manipulate with client-side
script.
'--- the array needs to live outside a procedure so it's available to all
scripts on the page
%>

If you've got a lot of items, that client-side code is going to get huge in
a hurry and may take a while to download to the browser. However, I do
something similar with two Listboxes, one with vehicle makes and one with
vehicle models, the two linked together to popuplate the model based on the
make...that's about 500 lines, plus a lot of other code (one page is almost
2500 lines long when all the server-side stuff is done...employee lists,
zipcode lists, city lists...) and it loads without any appreciable lag time.

Hope this helps,

Wm
 
K

KP

Hi William
Thank you so much for taking the time out to answer my question so
thoroughly.

I've used your suggestion and its working a treat. I now just have a
problem with my array so I now just need to mess about with it a bit to
get it right. I hate multi-dimensional arrays but in this case it is
very necessary :)

I may be back if I can't figure it out!

Thanks again.
Kathryn.
 
W

WIlliam Morris

I've had lots of occasion to work with multidimensional arrays since joining
the company I'm with. I hate working with recordsets, especially SHAPED
recordsets, preferring instead to get the recordset into an array and
closing it as soon as possible. It's not uncommon to find references like:

response.write employeeArray(1, 2)(3, 4)

where an element of a multidimensional array ~contains~ a multidimensional
array. Of course, javascript doesn't support them so then you have to work
with arrays of arrays, as in

MakeArray[0] = "Ford"
MakeArray[0][0] = "Escort"
MakeArray[0][1] = "Fairland"
MakeArray[0][2] = "Maverick" // have I given away my age yet?

and so on.
 
R

Ray at

Should item [0][1] be "Fairlane?" I especially like the Talladega edition.
I wonder how many still exist. :]

Ray at work
 
W

WIlliam Morris

Erk. Fairlane...you're right! There are a couple in my town in mint
condition...one periodically uses our parking lot at breakfast time (we
share our building with an Italian restaurant).

Ray at said:
Should item [0][1] be "Fairlane?" I especially like the Talladega edition.
I wonder how many still exist. :]

Ray at work


MakeArray[0] = "Ford"
MakeArray[0][0] = "Escort"
MakeArray[0][1] = "Fairland"
MakeArray[0][2] = "Maverick" // have I given away my age yet?

and so on.
 
K

KP

Thanks William, I think I've finally got my head around arrays and this
bit of my application is now working perfectly thanks to your help!

As for the cars I'm afraid I've not heard of some of the ones you are
talking about being that I'm from the UK! And being that I'm young ;-)

Kathryn.
 
W

William Morris

Glad to hear it Kathryn. I'm not sure what the automotive equivalents are
across the Pond, so we'll just let that one go. :)

Warmest regards,

William Morris
Product Development, Seritas LLC
 

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