protected void Page_Load(object sender, EventArgs e)
        {
            if (!Page.IsPostBack)
            {
                // Temporary data fetched through a list. In production you will fetch data from the database
                Make make = new Make();
                ddlMake.DataSource     = make.GetMake();
                ddlMake.DataTextField  = "Name";
                ddlMake.DataValueField = "Id";
                ddlMake.DataBind();

                if (ViewState["dt"] != null)
                {
                    DataTable dt = ViewState["dt"] as DataTable;
                    gvItems.DataSource = dt;
                }
            }
        }