Detailsview to have Session variable

 I'm trying to use a SessionVariable for a user name called ModifiedByName and put it into a hidden Edit item Template field in a Detailsview. How can I get the detailsview to accept the session Variable and update the DB when the user selects update?
This is my Template: <asp:TemplateField HeaderText="Modified By" SortExpression="ModifiedBy" Visibility="False"> <EditItemTemplate> <asp:TextBox ID="TextBox2" runat="server" Text='<%# Bind("ModifiedBy") %>'></asp:TextBox> </EditItemTemplate> <InsertItemTemplate> <asp:TextBox ID="TextBox18" runat="server" Text='<%# Bind("ModifiedBy") %>'></asp:TextBox> < ...