Question

I’m trying to create an option to select a specific entry in a SQL table if multiples exists. The Sub listed below is for a textbox (MOTxt) and a button (GotMO) for checking an MO# to pull from SQL. Based on the number entered, will populate other text boxes on the page with that row’s data. There are exceptions to this, where the MONumber will be entered more than once with different data associated with each entry. So, here’s my situation. If we have a duplicate MONumber listed in the table, it will populate the textboxes with the first entry it finds for an update.
I would like to create a dynamic dropdownlist (that displays only if multiples are found) displaying the ‘Name’ field entries for each MONumber found, then once the correct name is selected from that list, to then populate the textboxes with that selected datarow.

Here’s my code behind:

Protected Sub GotMONum_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles GotMO.Click
    Dim da As New SqlDataAdapter
    Dim ds As New DataSet
    Dim MOLength As String = MOTxt.Text
    Dim TieOffTemp As Integer
    Dim QTYTemp As Integer
    Dim MySelectQuery As String = "SELECT Name,ProdLine,NoRods,TieOffs FROM z_md_Outwrap WHERE MONumber = @MONum"
    Dim myConnection As New SqlConnection(ConfigurationManager.ConnectionStrings("GLoomisDBConnectionString").ConnectionString)
    Dim myCommand As New SqlCommand(MySelectQuery, myConnection)

    Message2.InnerHtml = ""
    Message.InnerHtml = ""
    If (Me.MOTxt.Text = "") Then
        MsgBox("Please enter an MO Number to check")
    Else
        ' Fills fields based on MO Number
        myCommand.Parameters.AddWithValue("@MONum", MOTxt.Text)
        myConnection.Open()
        da.SelectCommand = myCommand
        da.Fill(ds, "tblData")
        myConnection.Close()

        If ds IsNot Nothing AndAlso ds.Tables.Count > 0 AndAlso ds.Tables(0).Rows.Count > 0 Then
            NameTxt.Text = ds.Tables("tblData").Rows(0).Item("Name")
            ProdLineTxt.Text = ds.Tables("tblData").Rows(0).Item("ProdLine")
            NoRodsTxt.Text = ds.Tables("tblData").Rows(0).Item("NoRods")
            TieOffsTxt.Text = ds.Tables("tblData").Rows(0).Item("TieOffs")

            If Integer.TryParse(NoRodsTxt.Text, QTYTemp) Then
                If Integer.TryParse(TieOffsTxt.Text, TieOffTemp) And TieOffTemp > 0.0 Then
                    AmountVal.Text = "$" & (QTYTemp * TieOffTemp * 0.18)
                End If
            End If
        Else
            Message.InnerHtml = "No MO# found as entered. Please check for errors."
            Message.Style("color") = "red"
        End If
    End If

End Sub

Answer 1

If I were doing this, I would change the code so that the contents in your click function are in a separate functions so that you can recall it easily from other functions. I would use a strongly typed object instead of a dataset for added symplicity. Also add a couple of string arguments to the “Load Data” function to accept monum and name strings.

To find multiples, just check the count of what the database returns (datatable.rows.count or StronglyTypedObject.count)

Next, create a invisible dropdownlist control and set it to visible if your row count is > 0.

using Linq, binding the dropdownlist is fairly straight forward. Then call the new “load data” event on the onselectedindexchanged event passing the name selected along with the monumber.

I will not go into filling a strongly typed object as this question is already asking for alot, but to get you started… The following code example is just that and should not be taken as the actual code you will use.

Protected Sub GotMONum_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles GotMO.Click

  loaddata(monum.text, "")
end sub

protected sub loaddata(byval monum as string, byval name as string)
  'your code here along with the following lines after:
  Dim MySelectQuery As String = ""
  myCommand.Parameters.AddWithValue("@MONum", MOTxt.Text)

  if not string.isnullorempty(name)
    MySelectQuery = "SELECT Name,ProdLine,NoRods,TieOffs FROM z_md_Outwrap WHERE MONumber = @MONum and Name = @name"
    mycommand.Parameters.AddWithValue("@Name", Name)
  else
    MySelectQuery = "SELECT Name,ProdLine,NoRods,TieOffs FROM z_md_Outwrap WHERE MONumber = @MONum "
  End If
  'again, instead using a dataset, convert it to a list(of StronglyTypedObject)

  if StronglyTypedObject.count > 0 then
     dropdownlist.visible = true
     dim dropdownlistcontents = (from a in StronglyTypedObject.AsEnumerable _
                              Select a.Name).Distinct
     dropdownlist.datasource = dropdownlistcontents
     dropdownlist.databind
  end if
end sub

Protected Sub DDL_OnSelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) handles dropdownlist.selectedindexchanged
   loaddata(monum.text, "dropdownlist.selectedvalue")
end sub

Hopefully this gets you on your way… – Mutek