[resolved] Combobox Autofind

[jcfowl]

We have severe issues with the combobox control in .Net 2003 at work. Basically when you type in something in the combobox it will look like the combobox finds the matching item, but it doesn't. I'm trying to write some AutoFind code to fix this.

Private Sub cmb_KeyUp _
   ( _
   ByVal sender As Object, _
   ByVal e As System.Windows.Forms.KeyEventArgs _
   ) Handles cmb.KeyUp
 
   Call Me.SelectComboboxItem(sender)
   e.Handled = True
 
End Sub
 
Private Sub SelectComboboxItem(ByVal p_cmb As ComboBox)
 
   Dim retVal As Integer
   Dim txtLen As Integer
 
   txtLen = p_cmb.Text.Length
   p_cmb.Tag = p_cmb.Text
   retVal = p_cmb.FindString(p_cmb.Text)
 
   If retVal <> -1 Then
      p_cmb.SelectedIndex = retVal
      'code below is ignored, entire text is selected
      p_cmb.SelectionStart = txtLen
      p_cmb.SelectionLength = p_cmb.Text.Length - txtLen
   End If
 
End Sub

Everything works except the SelectionStart and SelectLength parts. The properties change but when the code actually runs the entire text is selected instead of just selecting the letters that were filled in for the user. Anyone have any ideas on how to make this functionality work?

[spjansen]

wasnt there something about selection in vb6, that you have to set the length first and after that you set the start?
I dont realy remember, but it's worth a try.

[jcfowl]

Thanks for the response spjansen, but that didn't work, it's strange because I see that the values for SelectionStart and SelectionLength are changing to values I need but It just doesn't do that on the screen... so confusing.

I know that its the basic functionality for the combobox to select the entire text on the change of an item but there has to be a way to override that.

[jcfowl]

got the basic functionality of it to work...

Private Sub cmb_KeyUp _
   ( _
   ByVal sender As Object, _
   ByVal e As System.Windows.Forms.KeyEventArgs _
   ) Handles cmb.KeyUp
 
   Call Me.SelectComboboxItem(sender)
   e.Handled = True
 
End Sub
 
Private Sub SelectComboboxItem(ByVal p_cmb As ComboBox)
 
   Dim retVal As Integer
   Dim txtLen As Integer
 
   txtLen = p_cmb.Text.Length
   retVal = p_cmb.FindString(p_cmb.Text)
 
   If retVal <> -1 Then
      'p_cmb.SelectedIndex = retVal
      
      'set SelectedItem, Not SelectedIndex (this doesn't highlight all text)
      p_cmb.SelectedItem = p_cmp.Items.Item(retVal)
      p_cmb.SelectionStart = txtLen
      p_cmb.SelectionLength = p_cmb.Text.Length - txtLen
   End If
 
End Sub

[jcfowl]

finished code... I'd love for some feedback on the functionality if anyone wants to test it out. Any suggestions for change are welcome.

I'm trying to mimic the old vb6 comobox on the forms 2.0 library where you could set the AutoFind flag to select combobox values.

Private Sub cmb_KeyUp _
   ( _
   ByVal sender As Object, _
   ByVal e As System.Windows.Forms.KeyEventArgs _
   ) Handles cmb.KeyUp
 
   If e.KeyValue >= Keys.A And e.KeyValue <= Keys.Z _
      Or e.KeyValue >= Keys.NumPad0 And e.KeyValue <= Keys.NumPad9 _
      Or e.KeyValue >= Keys.D0 And e.KeyValue <= Keys.D9 Then
 
      Call SelectComboboxItem(sender)
 
   End If
 
End Sub
 
Private Sub SelectComboboxItem(ByVal p_cmb As ComboBox)
 
   Dim retVal As Integer
   Dim txtLen As Integer
 
   If p_cmb.Text.Length = 0 Then Exit Sub
   txtLen = p_cmb.Text.Length
   retVal = p_cmb.FindString(p_cmb.Text)
 
   If retVal <> -1 Then
      p_cmb.SelectedItem = p_cmp.Items.Item(retVal)
      p_cmb.SelectionStart = txtLen
      p_cmb.SelectionLength = p_cmb.Text.Length - txtLen
   End If
 
End Sub