Pass value from GridView to another page using Session and QueryString in ASP.Net

use this

 html

<asp:HyperLinkField ItemStyle-Width="25%" DataNavigateUrlFields="column1,column2" DataNavigateUrlFormatString="page2.aspx?columnvalue1={0}&columnvalue2={1}" DataTextField="ContractSBU" HeaderText="Brand" ControlStyle-ForeColor="#000000" ControlStyle-Font-Underline="false"></asp:HyperLinkField>

behind the code to the page2

TextBox1.Text = Request.QueryString["columnvalue1"];
TextBox2.Text = Request.QueryString["columnvalue2"];