DataRelation - DataBinding - Child table update problem

I have the following code.

vb.net Code:

Const ConnectionString As String = "server=YOURSERVERNAME;database=tempdb;uid=sa;pwd=YOURPASSWORD"
 
    Dim MyDataset As New DataSet
    Dim CustomersDA, AddressesDA As SqlDataAdapter
    Dim CustomersTable, AddressesTable As DataTable
    Dim bsParent, bsChild As BindingSource
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        ReBind()
    End Sub
 
    Private Sub UpdateDBButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles UpdateDBButton.Click
        AddressesDA.Update(AddressesTable)
        CustomersDA.Update(CustomersTable)
        ReBind() '' refill to test whether changes were updated in db.
    End Sub
 
    Private Sub ReBind()
        MyDataset = New DataSet
        CustomersDA = New SqlDataAdapter("select Customers.* from Customers", ConnectionString)
        AddressesDA = New SqlDataAdapter("select Addresses.* from Addresses", ConnectionString)
        Dim cmdBldr As New SqlCommandBuilder(CustomersDA)
        CustomersDA.UpdateCommand = cmdBldr.GetUpdateCommand
        cmdBldr = New SqlCommandBuilder(AddressesDA)
        AddressesDA.UpdateCommand = cmdBldr.GetUpdateCommand
 
        CustomersDA.Fill(MyDataset, "Customers")
        AddressesDA.Fill(MyDataset, "Addresses")
 
        CustomersTable = MyDataset.Tables("Customers")
        AddressesTable = MyDataset.Tables("Addresses")
        MyDataset.Relations.Add("MyRelation", CustomersTable.Columns("CustomerId"), AddressesTable.Columns("CustomerId"))
 
        bsParent = New BindingSource
        bsChild = New BindingSource
        bsParent.DataSource = MyDataset
        bsParent.DataMember = "Customers"
        bsChild.DataSource = bsParent
        bsChild.DataMember = "MyRelation"
 
        Me.DataGridView1.DataSource = bsParent
        Me.DataGridView2.DataSource = bsChild
        TextBox1.DataBindings.Clear()
        TextBox2.DataBindings.Clear()
        TextBox1.DataBindings.Add("Text", bsParent, "CustomerName")
        TextBox2.DataBindings.Add("Text", bsChild, "City")
    End Sub

The problem is that I can see all changes on screen (dataset) whether made from GridViews or the TextBoxes. But the Child Table doesn't update changes to database that were made from the databound textbox (i.e. TextBox2). All other changes are updated.

What am I doing wrong?

Attached is a sample project that depicts the problem and a sql script file to create sample data.

Nevermind.. I figured out myself.

The DataGridViews automatically call the BindingSource.EndEdit when changing rows. THe textboxes don't call this method. THe changes are updated in Datatables though the RowState remains unchanged. This is mysterious and looks like a bug. Shouldn't the RowState change when data changes?

Anyways, since the problem is known, the solution is easy. Just manually call BindingSource.EndEdit() on respective BindingSources. TextBox Validating method looks like the most appropriate event.

So putting the following code corrects the problem.

vb.net Code:

Private Sub TextBox1_Validating(sender As Object, e As System.ComponentModel.CancelEventArgs) Handles TextBox1.Validating
    Me.bsParent.EndEdit()
    Me.bsParent.CurrencyManager.Refresh()
End Sub
 
Private Sub TextBox2_Validating(sender As Object, e As System.ComponentModel.CancelEventArgs) Handles TextBox2.Validating
    Me.bsChild.EndEdit()
    Me.bsChild.CurrencyManager.Refresh()
End Sub