Data binding update problem

I am having a problem getting a single field to update a dataset. In my "SaveInvoice" sub, I have several labels with a tag property that is bound to a field in the dataset. Before updating the underlying tables, I am assigning the proper values to the .tag properties of the various labels, and then doing an "EndCurrentEdit." However, when I update the database, I find that one of the properties did not update properly. If I step through the code line by line and check out the values, I see that all the tag properties have the proper value until executing the line with the EndCurrentEdit, at which point, the lblInvoiceStatus.tag reverts back to what it was before, for no apparent reason. None of the other tags seem to be doing this. I am using the ComponentOne data navigator thingie (C1InvoiceNavigator) and am calling the EndCurrentEdit method through it. Here is the code:

Code:

---

    Private Sub SaveInvoice()
        Try
            'Save the current invoice to dataset and update the database
           
            Me.lblCustName.Tag = mintCurrentCustomer
            Me.lblInvVehicle.Tag = mintCurrentVehicle
            Me.lblInvoiceStatus.Tag = mintCurrentStatus

            'Convert tax and total values to decimal values and store in the .tag properties
            Me.lblSalesTax.Tag = IIf(Me.lblSalesTax.Text <> "", CType(Me.lblSalesTax.Text, Decimal), 0D)
            Me.lblTotal.Tag = IIf(Me.lblTotal.Text <> "", CType(Me.lblTotal.Text, Decimal), 0D)
            Me.lblBalanceDue.Tag = IIf(Me.lblBalanceDue.Text <> "", CType(Me.lblBalanceDue.Text, Decimal), 0D)

            'End the current edit
            Me.C1InvoiceNavigator.BindingContext(Me.dsInvoices1, "tblInvoices").EndCurrentEdit()

            'Update the underlying tables
            Me.daInvoices.Update(Me.dsInvoices1.tblInvoices)
            Me.daInvoiceDetails.Update(Me.dsInvoices1.tblInvoiceDetails)
            mblnNewInvoiceMode = False
            mblnInvoiceIsDirty = False
        Catch ex As Exception
            MsgBox(ex.StackTrace & vbCrLf & vbCrLf & "Error: " & ex.Message, MsgBoxStyle.Critical, "Error")
        End Try

    End Sub

---

Any ideas why the EndCurrentEdit is causing lblInvoiceStatus.tag to revert back to its previous value?

Thanks,
Ken

Hi,

I haven't used this aproach to data editing but it looks as if your approach differs slightly from that recommended in MSDN help. Have a look at

BindingManagerBase.EndCurrentEdit Method

and compare it with your approach.

I checked it out, and the first paragraph says this:

Quote:

---

Remarks
This method is supported only if the data source implements the IEditableObject interface. In that case, changes will be saved. If the object does not implement the IEditableObject interface, changes made to the data will not be saved.

---

So now I'm more confused than ever. Apparently, the only thing that implements the IEditableObject interface is a DataRowView. I'm guessing that when binding form objects to a data source, that you are actually binding to a DataRowView, right?

I checked out their code samples, but the thing is, I thought with databinding, all that stuff was taken care of automatically. Their code is explictly creating a new datarow and modifying the values and replacing the old one, etc. Why do we have to do all of that?

I think the solution will be to write the modified values directly to the DataRow in the Dataset and say the heck with the stupid tag properties. If I'm right, then what good is databinding? I've kinda noticed that experienced programmers tend to hate databinding and prefer to do all the data manipulation manually. I guess this is why.

Thanks.

HI,

I use databinding when using a datagrid as I have had problems with using datasource property. Presumably you are using a dataadapter and a dataset?

Yeah. In the code I posted, daInvoices and daInvoiceDetails are the data adapters, dsInvoices1 is the dataset, and it contains two tables: tblInvoices and tblInvoiceDetails.

It's been over a week and I still can't squash this bug. The dataset is being updated properly. Everything in the dataset is as it should be. When I call the SaveInvoice sub, MOST of my data is saved to the database, with the exception of the lblInvoiceStatus.tag and also the lblClosedBy.Text. I have no idea why these particular two data bindings do not "stick" when all the other ones do.

I've even tried directly updating the values in the datatable in the dataset. I know that the values in the dataset are 100% correct, and the rowstate value for the modified rows is 16 (which means modified). I assume since the rowstate is modified, the data adapter would know to update the underlying database, and it is updating most of the values, but only the two values described above are not getting updated in the database.

Does anyone have any further suggestions for debugging this one? I've run out of ideas!

Thanks,
Ken