Add an extra header to an ASP.NET DataGrid

Public Class _Default
    Inherits System.Web.UI.Page

#Region " Web Form Designer Generated Code "

    'This call is required by the Web Form Designer.
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()

    End Sub
    Protected WithEvents g As WebApplication1.ExtraHeaderDataGrid

    'NOTE: The following placeholder declaration is required by the Web Form Designer.
    'Do not delete or move it.
    Private designerPlaceholderDeclaration As System.Object

    Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init
        'CODEGEN: This method call is required by the Web Form Designer
        'Do not modify it using the code editor.
        InitializeComponent()
    End Sub

#End Region

    Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        If Not IsPostBack Then
            'bind the grid to a dummy datasource
            g.DataSource = GetSource()
            g.DataBind()
        End If
    End Sub

    Private Sub g_ItemCreated(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.DataGridItemEventArgs) Handles g.ItemCreated
        If e.Item.ItemType = ListItemType.Header Then
            If e.Item.ID = "extraheader" Then

                Dim refreshCell As New TableCell
                refreshCell.ColumnSpan = 2
                refreshCell.HorizontalAlign = HorizontalAlign.Center
                Dim btnRefresh As New Button
                btnRefresh.Text = "Refresh"
                refreshCell.Controls.Add(btnRefresh)
                AddHandler btnRefresh.Click, AddressOf btnRefresh_Click

                Dim parentsCell As New TableCell
                parentsCell.ColumnSpan = 2
                parentsCell.HorizontalAlign = HorizontalAlign.Center
                parentsCell.Text = "Parents"

                e.Item.Cells.Add(refreshCell)
                e.Item.Cells.Add(parentsCell)
            End If
        End If
    End Sub

    Private Sub btnRefresh_Click(ByVal sender As Object, ByVal e As System.EventArgs)
        Response.Write("Refresh called from ExtraHeaderItem")
    End Sub

    'Get a dummy datasource
    Private Function GetSource() As DataTable
        Dim t As New DataTable

        'build columns
        t.Columns.Add("name")
        t.Columns.Add("age")
        t.Columns.Add("mothername")
        t.Columns.Add("fathername")

        Dim r As DataRow = t.NewRow
        r("name") = "David A"
        r("age") = 24
        r("mothername") = "Marcy A"
        r("fathername") = "Jimy A"
        t.Rows.Add(r)

        Dim r2 As DataRow = t.NewRow
        r2("name") = "Diana B"
        r2("age") = 30
        r2("mothername") = "Patricia A"
        r2("fathername") = "John B"
        t.Rows.Add(r2)

        Return t
    End Function

End Class