Combobox SelectedIndexChanged

I have a combobox that I am filling with data at form load. I also have code that adds data to another field when the SelectedIndex gets changed. Right now I have a SelectedIndex = -1 after the combobox is filled so that there is no value listed in the combobox when the form is finished loading.

The problem is that that SelectedIndex = -1 is tripping my SelectedIndexChange code block. This seems like I am attempting such a common task that there must be an easy workaround or I am really missing something obvious.

Any ideas?

You should do a check to see if SelectedIndex=-1 in the top of the SelectedIndexChanged method end exit if it is.

Thanks Pax. I tried that but since the records in the combobox get loaded and ordered alphabeticaly the IndexNumber starts out at 23 (The 23rd Record is (Abe) and then gets set to -1 as the form finishes loading, which is when the IndexXhanged gets fired.

Doing it this way the 23 is what gets tested not the -1. And I can't test for a 23 all the time either because it is possible that a record will get added that will be Aarron and will move ahead of record 23.

Anything else you can think of that I can try?

I use this same basic type of code every where I use a combobox:

VB Code:

If Me.cboLevel.SelectedIndex < 0 Then
            MessageBox.Show("You must select a User Level for this new user." & System.Environment.NewLine & _
                            "Please select a User Level from the provided list.", "No User Level Selected", MessageBoxButtons.OK, MessageBoxIcon.Warning)
            Me.cboLevel.Focus()
            Exit Sub
        Else
            intLevel = Me.intUserLevels(Me.cboLevel.SelectedIndex)
        End If

if the selectedindex is < 0 then the procedure exits. I also fill the combo box alphabetically, But if nothing is selected in the box the selectedindex is equal to -1
if the first item is selected then the selectedindex = 0 and so on...

Here is my entire codeblock

VB Code:

Private Sub cboMarketPiece_SelectedindexChanged( _
        ByVal sender As Object, ByVal e As System.EventArgs) _
        Handles cboMarketPiece.SelectedValueChanged
 
        If cboMarketPiece.SelectedIndex < 0 Then
            cboMarketPiece.Focus()
            Exit Sub
        Else
            Dim cnn As New OleDbConnection
            Dim cmd As New OleDbCommand
            Dim dr As OleDbDataReader
            cnn.ConnectionString = conBCA
            cmd = cnn.CreateCommand
            cmd.CommandText = "SELECT Number From " & _
                "queMarketingPiece Where MarketingPiece = '" & _
                cboMarketPiece.Text & "'"
            Try
                cnn.Open()
                dr = cmd.ExecuteReader
                While dr.Read()
                    txtMpCode.Text = dr("Number").ToString
                End While
                dr.Close()
            Catch ex As Exception
                Exit Sub
            Finally
                cnn.Close()
            End Try
        End If
    End Sub

The txtMpCode.Text = dr("Number").ToString is filling that box when it should not be because I set the Index to -1 at the form load. I did come up with a quick and dirty work around and that is to add this to the form load.

VB Code:

Private Sub frmCreateBarcode_Load( _
        ByVal sender As Object, ByVal e As System.EventArgs) _
        Handles Me.Load
 
        FillMarketingPiece()
        FillCouponOffer()
        txtMpCode.Clear()
        txtCoCode.Clear()
 
    End Sub
' The last line in FillCouponOffer and FillMarketingPieceOffer is cboXXX.SelectedIndex = -1

That seems to be doing the trick.