Loops gridview and email problem

Hi i have a VB.NET app which lookps up a table called tblClients for field ClientID. It also has a gridview which lists a grid of data where clientID = ClientID from table. Currently i have it setup so that on each loop the clientID gets set as the text of a textbox1. The gridview then uses the value of this textbox in the SQLDataSource. Then the gridview is rendered as a htmlstring and sent in an email. Somehow the gridview is not getting updated. Here is the code:
The code behind:


Imports System.Data.SqlClient
Imports System.Data
Imports System.IO

Partial Class EmailClient
    Inherits System.Web.UI.Page

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)

    End Sub

    ' render gridview to html
    Private Function RenderGridView() As String

      &nbs ...