internal static IphonePrice CreateIphonePrice(string type)
 {
     IphonePrice ip=null;
     switch (type)
     {
         case "Iphone5":
             ip= new Iphone5Price();
              break;
         case "Iphone6":
            ip= new Iphone6Price();
             break;
         default:
             break;
     }
     if (ip==null)
         throw new Exception();
     return ip;
 }
        internal static IphonePrice CreateIphonePrice(string type)
        {
            IphonePrice ip = null;

            switch (type)
            {
            case "Iphone5":
                ip = new Iphone5Price();
                break;

            case "Iphone6":
                ip = new Iphone6Price();
                break;

            default:
                break;
            }
            if (ip == null)
            {
                throw new Exception();
            }
            return(ip);
        }