Foros del web, para los que viven de bits

 Dim cnn As New SqlConnection(AppSettings("ActivitiesConnection"))
        Dim adap As New SqlDataAdapter("select * from actividades", cnn)
        Dim dtable As New DataTable
        adap.Fill(dtable)
        Me.DataGrid1.DataSource = dtable
        Me.DataGrid1.DataBind()

        Dim str As String
        Dim strbuild As System.Text.StringBuilder
        Dim strWriter, strWriter2 As System.IO.StringWriter
        strWriter = New System.IO.StringWriter
        strWriter2 = New System.IO.StringWriter

        Dim html As New System.Web.UI.HtmlTextWriter(strWriter)
        'me.datos = control  que contiene todo el html que se quiere obtener
        Me.DataGrid1.RenderControl(html)

        strWriter2 = html.InnerWriter
        strbuild = strWriter2.GetStringBuilder()

        'str contiene todo el html del control
        str = strbuild.ToString()