Getting a Cell Value from a GridView on RowDataBound

Hi, I'm having trouble getting a value from a cell/column in my GridView at runtime.  My first column is a Hyperlink field and I want to grab the value from the first column of the GridView and use it on the RowDataBound event to dynamically create the navigateUrl value.  The problem value is strUserID and UserID in the NavigateUrl string.  Thanks
Protected Sub GridView1_RowDataBound(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewRowEventArgs) If e.Row.RowType = DataControlRowType.DataRow Then Dim link = DirectCast(e.Row.FindControl("HyperLink1"), HyperLink) Dim strUserID As String = e.Row.Cells(0).Text Dim strBeginDate As String = txtBeginDate.Text Dim strEndDate As String = txtEndDate.Text link.NavigateUrl = "LAProductivityDetail.aspx?BeginDate=" & Server.UrlEncode(strBeginDate) & "&End ...