Dropdownlist OnSelectedIndexChanged not firing

meckeard · Oct 28, 2003

Hi,

I can't get the OnSelectedIndexChanged event to fire on a dropdownlist control.

Here is how my page is designed:

When my page loads, I have a dropdownlist with a list of states. When the user changes the dropdownlist, the AutoPostBack fires and runs a sub that loads & shows a second dropdownlist that shows cities for the state selected.

The problem occurs when I make a selection from the city dropdownlist. Nothing happens.

Here is my dropdownlist:

<form runat="server">
<asp

ropDownList ID="drpCityList" onfiltered="GetATMList" runat="server">
</asp

ropDownList>
</form>

Here is the code in a codebehind page:

Public Sub GetATMList(sender As Object, e As System.EventArgs)
'This sub loads the ATM's for the city selected.

Dim objConn As SqlConnection
Dim objSQLCommand As SqlCommand
Dim objDataReader as SqlDataReader
Dim strCity as String = drpCityList.SelectedItem.Text

if UCase(strCity) <> "NOW SELECT A CITY" then

'Set up our connection object and SQL command object.
objConn = New SqlConnection(application("WSFSQLConnString&quot

)
objSQLCommand = New SqlCommand("AD_s_GetATMByCity", objConn)
'Set the stored procedure.
objSQLCommand.CommandType = CommandType.StoredProcedure
'Add parameters.
objSQLCommand.Parameters.Add("@City", strCity)
'Open the db connection & Execute Command
objConn.Open()

'Execute the procedure.
objDataReader = objSQLCommand.ExecuteReader()
'Now bind the datareader to the repeater.
grdATMs.DataSource = objDataReader
grdATMs.DataBind()
'Close the DB connection.
objConn.Close()

end if

end Sub 'GetATMList

I tried to change the sub to set the value to a label, thinking maybe there was something wrong with the value of the dropdownlist. But it didn't work either.

What am I doing wrong?

Thanks,
Mark

Isadore · Oct 28, 2003

meck -

Cut and pasted you code into a simple page and when I changed:

onfiltered="GetATMList"

to

OnSelectedIndexChanged="GetATMList"

it worked. I also included a AutoPostBack="true"

Seems the onfiltered wasn't cutting it - although I like that approach. I found it interesting too that by using the OnSelectedIndexChanged handle for directly referencing a function instead of its accompanying handle, it worked fine.

This is the entirety of my page:

<%@ Page Language="vb" Debug="true" %>
<%@ Import Namespace = "Microsoft.VisualBasic" %>
<%@Import Namespace = "System"%>
<script runat="server">
Public Sub GetATMList(sender As Object, e As System.EventArgs)
lblTest.Text = "Fire away"
End Sub
</script>
<HTML>
<HEAD>
<title>Test</title>
</HEAD>
<body>
<form runat="server">
<asp

ropDownList ID="drpCityList" OnSelectedIndexChanged="GetATMList" AutoPostBack="true" runat="server">
<asp:ListItem Value="01">A</asp:ListItem>
<asp:ListItem Value="02">B</asp:ListItem>
<asp:ListItem Value="03">C</asp:ListItem>
</asp

ropDownList>
<asp:Label id="lblTest" runat="server"/>
</form>
</body>
</HTML>

meckeard · Oct 28, 2003

Isadore,

Opps, sorry. I had it that way from the start. I did a View -> Source and that is what is sent to the browser. Sorry!

Let me take a step back and describe exactly what I am trying to do.

When the page is first loaded, I bind a dropdownlist with all states. When the user makes a state selection, I bind & show the second dropdownlist for all cities for the selected state (control in question). When the user selects a city, I want to run a sub that binds & shows a datagrid with some results based on the city selection.

With that said, I think that my problem is in the script part of the page. How do I code to decide to show the city dropdownlist, then show the datagrid only after the city dropdownlist has been changed?

Thanks,
Mark

Isadore · Oct 28, 2003

meck --

I've only been at .net for a year now, doing other things a well, so not a guru like some of these guys -- although I admit I learned much from them (jfrost, custom, Paul, et al.)

In your case what I would do is simply post back after a City is selected, and from the OnSelectedIndexChanged handle I would add code to bind the datagrid and then make the datagrid visible. For example,

1. User selects a city, post back.

2. In the OnSelectedIndexChanged handle I would have something like
...
GetCtyDetail(ddCty.SelectedItem.Index)
dgMyGrid.Visible = "True"
...
Sub GetSites (intID As Integer)
'bind grid
End Sub

In the SQL of the DataGrid you can use of course the value from the Cty dropdown - something along these lines.

Anyway, a simple approach (and I have not scrutinized your code above). Someone may come by and add some further insight, what initially caught my eye was your use of the "filert" statement.

Isadore · Oct 28, 2003

meck -

better, just ref the dropdown in the dgrid bind SQL and you don't need to pass the variable --

meckeard · Oct 28, 2003

All,

I got it to work. I needed to play around with the postback a little to detect the seletion of the city.

Thanks all for the help & insight.

I am still stuck on another problem, posted here:

thread855-690359 anyone gets bored, take a look and let me know if you can help.

Thanks,
Mark

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Dropdownlist OnSelectedIndexChanged not firing

meckeard

Programmer

Isadore

Technical User

meckeard

Programmer

Isadore

Technical User

Isadore

Technical User

meckeard

Programmer

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