Data Binding in .NET with CSLA BOs
OK, I am having quite an issue with data bindi开发者_如何学编程ngs in .NET.
Some background information, my business object tier is using CSLA v1.0. And _clientObj is passed in as a parameter as a business object that inherits CSLA.BusinessBaseHere is the code segment:
Dim nextClient As New ComboBox With { _
.Name = "txtClientAtt" & (ClientBoxes.Count + 1).ToString(), _
.DisplayMember = "FullNameAndID", .ValueMember = "ClientID", _
.Tag = _clientObj}
nextClient.DataSource = ClientList.GetClientList(SelectedSite)
nextClient.DataBindings.Add("SelectedValue", _clientObj, "ClientID")
If Not _clientObj.ClientID = Nothing AndAlso nextClient.SelectedValue Is Nothing Then
Debug.Print("How could I ever be inside this conditional????")
End If
That debug statement does indeed get reached if _clientObj is a pre-existing object with an assigned ID value. How is that possible? I was assuming that adding the data binding should immediately set the .SelectedValue property of the ComboBox if the DataSource object has an initial value.
If Not _clientObj.ClientID = Nothing
is not the correct way to test for a null value. You should be using:
If Not _clientObj.ClientID Is Nothing
However, I'm not sure if that is actually the issue you are having or not.
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