private void RebindOrders()
 {
     int employeeId = Convert.ToInt32(this.GridViewEmployees.SelectedValue);
     var context = new NorthwindEntities();
     this.GridViewOrders.DataSource = context.Orders.Where(o => o.EmployeeID == employeeId).ToList();
     this.GridViewOrders.DataBind();
 }
 protected void Page_Load(object sender, EventArgs e)
 {
     if (!Page.IsPostBack)
     {
         var context = new NorthwindEntities();
         this.GridViewEmployees.DataSource = context.Employees.ToList();
         this.GridViewEmployees.DataBind();
         this.RebindOrders();
     }
 }