dropdown lists - query parameter error

  • Thread starter Thread starter KathyB
  • Start date Start date
K

KathyB

Hi,

I'm using the following for 2 dropdown boxes in asp.net. The first is
the basis for the contents of the second. First works fine, then on
its selectedindexchanged event I get "No value given for one or more
required parameters" error.

I've had it worked ok before using datasets, but can't get it to work
with datareader.

Any hints welcome. Thanks, Kathy

Private Sub Page_Load(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles MyBase.Load
'Put user code to initialize the page here

If Not IsPostBack Then

Dim Conn1 As OleDbConnection
Dim Rdr1 As OleDbDataReader
Dim Cmd1 As OleDbCommand
Dim strSQL As String

Conn1 = New OleDbConnection(strConn)

strSQL = "SELECT DISTINCT Customer FROM tblCustomers"
Cmd1 = New OleDbCommand(strSQL, Conn1)
Conn1.Open()
Rdr1 = Cmd1.ExecuteReader()
cboCust.DataSource = Rdr1
cboCust.DataBind()
cboCust.Items.Insert(0, "Select Customer")
cboCust.SelectedIndex = 0
Rdr1.Close()

Conn1.Close()

End If
End Sub

Private Sub cboCust_SelectedIndexChanged(ByVal sender As
System.Object, ByVal e As System.EventArgs) Handles
cboCust.SelectedIndexChanged

'If Not IsPostBack Then

Dim Conn2 As New OleDbConnection()
Dim Rdr2 As OleDbDataReader
Dim Cmd2 As OleDbCommand
Dim strSQL2 As String

Conn2 = New OleDbConnection(strConn)

strSQL2 = "SELECT Assy FROM tblAssy WHERE ([Customer] =
@customer)"
Dim prmCustomer As OleDbParameter = New
OleDbParameter("@customer", OleDbType.VarChar, 50)
Conn2.Open()
Cmd2 = New OleDbCommand(strSQL2, Conn2)
prmCustomer.Value = cboCust.SelectedItem.Value
Rdr2 = Cmd2.ExecuteReader()
cboAssy.DataSource = Rdr2
cboAssy.DataBind()
cboAssy.Items.Insert(0, "Select Assembly")
cboCust.SelectedIndex = 0
Rdr2.Close()
Conn2.Close()

'End If
End Sub
 
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