Cookies being automatically empty

I have cookies named empid which stores the id of employee i am going to use. But whenever i try to get the value of any cookie its value is set to null automatically and this code is from a partial class which is inherited by page . What if i want to create a class that contains all the database related code and want to use it in everypage

protected void Page_Load(object sender, EventArgs e)
{
    using (SqlConnection cn = new SqlConnection(ConfigurationManager.ConnectionStrings["MyDbConn"].ToString()))
    {

        using (SqlCommand cmd = new SqlCommand())
        {
            try
            {

                cn.Open();
                SqlDataReader conReader;
                conReader = null;
                mycomment.Text = Response.Cookies["empid"].Value;
                // cmd.CommandText = "Select * from comments where c_from = " + Response.Cookies["cid"] + " and c_to = "+ Response.Cookies["empid"].ToString();
                cmd.Connection = cn;
                mycomment.Text = cmd.CommandText;
                cmd.CommandType = CommandType.Text;
                conReader = cmd.ExecuteReader();

                while (conReader.Read())
                {
                    mycomment.Text += conReader[3].ToString();

                }

            }

            catch (Exception ex)
            {
                Console.Write(ex);
            }
            finally
            {
                cn.Close();
            }

        }
    }
}