postback causes delay

[wizard04]

I have a drop-down list, populated from a database, a few text boxes,
and a few buttons on a page. The ddl is set to autopostback.

For some reason, whenever a postback happens (when an item in the ddl
is selected or a button is clicked) the page is processed immediately
and is sent back to the browser, but after the browser displays the
first 50-75% of the page, it stops for about 60 seconds before
displaying the rest.

As far as I can tell it's not a server problem, because I set
trace=true and the page was processed in less than a second. However,
the same thing happens in IE6.0 and Firefox 1.0.7 on my WinXP computer
and in IE5.5 on my Win2000 computer, so I'm not sure where the problem
is. The only client-side code is javascript to set the focus to the
first textbox: document.getEle mentById("tb_pr efix").focus();
and the server-generated _doPostBack function.

Any ideas?
Thanks

[wizard04]

Correction: it's a listbox, not a drop-down list

[clintonG]

In ASP we used to solve this problem by setting Response.Buffer = true so
all controls and contents of the page would be processed before the page was
displayed. I suspect the is a control that is giving the Response object a
hard time. How are you populating the ListBox for example? Kill ViewState
and test the page and so on.
<%= Clinton Gallagher
METROmilwaukee (sm) "A Regional Information Service"
NET csgallagher AT metromilwaukee. com
URL http://metromilwaukee.com/
URL http://clintongallagher.metromilwaukee.com/
"wizard04" <wi**********@h otmail.com> wrote in message
news:11******** *************@z 14g2000cwz.goog legroups.com...

Correction: it's a listbox, not a drop-down list

[wizard04]

I'm populating the listbox when the page first loads, when an item is
removed from the list (one of the buttons), or when an item is added or
updated (another button). I use a function as follows:

Sub doDataBind()

Dim ds As New System.Data.Dat aSet
Dim sql As String
Dim myDbConnection As OleDbConnection
Dim myDbCommand As OleDbCommand
Dim myDbDataAdapter As OleDbDataAdapte r

sql = _
"SELECT * " & _
"FROM Customer " & _
"ORDER BY LastName, FirstName, UserName"

myDbConnection = New OleDbConnection (strConn_Report Cards)
myDbCommand = New OleDbCommand(sq l, myDbConnection)
myDbDataAdapter = New OleDbDataAdapte r(myDbCommand)

myDbDataAdapter .Fill(ds)

myDbConnection. Close()

lb_customers.Da taSource = ds
lb_customers.Da taBind()

End Sub

with strConn_ReportC ards being the connection string to my Access
database.

I just tried turning off viewstate in the @Page directive, but that
didn't help.

[wizard04]

Actually, the listbox isn't even populated now that viewstate's off.

[clintonG]

I meant to turn off ViewState just to see what can be observed. I see you
need to get out of the habit of using the * metacharacter with your Select
statement. Use the actual names of the fields to avoid a performance penalty
when hitting the database. What if your table has a bunch of fields? The
metacharacter will select each field in the table and must determine which
field will or will not be used in the rest of the query.

The rest of your code looks fine. Then, if the contents of the ListBox do
not need to be changed with each PostBack I would suggest learning how to
cache the contents of the ListBox. That should about do it other than the
last suggestion to dump JET and use SQL Server as performance is much much
much better. How many other pages may be hitting that same database at the
same time? JET is a monolithic file. All requests get processes single file
injun style which I hear is no longer nice to say but I sure wonder where
the saying come from :-)

<%= Clinton Gallagher
METROmilwaukee (sm) "A Regional Information Service"
NET csgallagher AT metromilwaukee. com
URL http://metromilwaukee.com/
URL http://clintongallagher.metromilwaukee.com/
"wizard04" <wi**********@h otmail.com> wrote in message
news:11******** **************@ g44g2000cwa.goo glegroups.com.. .

Actually, the listbox isn't even populated now that viewstate's off.

[clintonG]

While doing some housekeeping I came upon this resource by David Hayden [1].

<%= Clinton Gallagher

[1] http://davidhayden.com/blog/dave/arc...8/24/2439.aspx

"wizard04" <wi**********@h otmail.com> wrote in message
news:11******** **************@ g44g2000cwa.goo glegroups.com.. .

Actually, the listbox isn't even populated now that viewstate's off.

[wizard04]

Thanks Clinton, I'll try out your suggestions :-)

[wizard04]

I decided to make a simple test first. The following code (only two
buttons) has the same problem:

<%@ Page Language="VB" ContentType="te xt/html"
ResponseEncodin g="iso-8859-1" Trace="false" EnableViewState ="true" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html;
charset=iso-8859-1">
<title>test</title>
<script runat="server">
Sub Page_Load(sende r As Object, e As EventArgs)
If Not IsPostBack then
response.Write( "Not IsPostBack<br>" )
else
response.Write( "IsPostBack<br> ")
end if
End Sub
Sub doA(sender As Object, e As EventArgs)
response.Write( "A Clicked<br>")
End Sub

Sub doB(sender As Object, e As EventArgs)
response.Write( "B Clicked<br>")
End Sub
</script>
</head>
<body>
<form runat="server" id="theForm">
<asp:Button ID="btn_A" runat="server" Text="A" OnClick="doA"/>
<asp:Button ID="btn_B" runat="server" Text="B" OnClick="doB"/>
</form>
</body>
</html>

[wizard04]

(same thing with EnableViewState ="false")