Simple Way to Hide the Query String Value In a GrideView HyperLink Field

I have a GrideView that has a Hyperlink field.  Currently I’m passing the RequestID to another page using the query string method.  Is there a simple way I can still pass the value to other page without the user seeing the value in their address bar? 
<asp:TemplateField> <ItemTemplate> <asp:HyperLink ID="HyperLink1" runat="server" NavigateUrl='<%# Eval("RequestID", "Testing.aspx?ReqID={0}") %>' Text="View"></asp:HyperLink> </ItemTemplate> </asp:TemplateField> Angel