This still does not provide sufficient detail. The code you reference here sheds no light on how the UltraComboEditor items might be getting cleared. If you have code anywhere in the application that uses the UltraComboEditor.Items.Clear method, put a breakpoint there and see if it gets hit. If you aren't clearing them anywhere, another possibility is that the data source is getting cleared or the control's DataSource property is being set to null somewhere.

UltraNumericEditor retains focus by default when the value is invalid. It fires the ValidationError event; you can handle this event and set the RetainFocus property of the event arguments to false to prevent it from trapping the user.

I'm dying here.

Any help, please???

Brian Fallon"]

It is impossible for us to help you without additional details. If possible please attach a simple sample and provide an explanation about what is going wrong, i.e., what you mean by "the whole form was reset".

Hi, Brian. Below is my coding.

Private Sub cboProductCode_SelectionChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles cboProductCode.SelectionChanged
        GetSize(cboProductCode.SelectedItem.DataValue)
    End Sub

While Form_Load, I bind some data into some UltraComboEditors for user to select, after the above code, it will return a value to UltraNumericEditor. But all UltraComboEditors become empty, just like it was a brand new form.

And I also found out that when I point the cursor to UltraNumericEditor, the cursor will remain in the control, I couldn't select other control.