Hi,
You can use Sesson object, That will be unique to http session.
You can use below code to store data into session.
Session["POLICYNO"] = policy_number;
Then you can access policy number in other page with below code.
int policy_number;
if(Session["POLICYNO"] != null)
{
policy_number = Convert.ToInt32(Session["POLICYNO"].ToString());
}
else
{
}
Hope this will help you.