Serialisierung von Objekten in xml

Question

Ich habe Methoden, die Objekte erstellen, dann an eine andere Methode gesendet werden, die einige Operationen ausführen wird, und schließlich wird es in eine XML-Datei serialisiert. das Problem. Das XML hat nur das letzte Objekt, das erstellt wurde, es fehlen die ersten 15 von ihnen.

public void reserveRoom() 
    { 
     reserveRoom("2345", "20160905", 1, "00001", "KB"); 
     reserveRoom("2345", "20160905", 4, "00002", "KB"); 
     reserveRoom("2345", "20160905", 5, "00003", "KB"); 
     reserveRoom("2345", "20160907", 3, "00004", "KB"); 
     reserveRoom("2345", "20160909", 4, "00005", "KB"); 
     reserveRoom("2345", "20160906", 5, "00006", "KB"); // fails - room not available 
     reserveRoom("2345", "20160905", 1, "00007", "QB"); 
     reserveRoom("2345", "20160905", 1, "00008", "KB"); // fails- room not available 
     reserveRoom("2345", "20160905", 4, "00009", "QB"); 
     reserveRoom("2345", "20170905", 1, "00010", "KB"); // fails- room not available 
     reserveRoom("7890", "20160915", 5, "00011", "QB"); 
     reserveRoom("7890", "20160925", 10, "00012", "QB"); // fails- room not available 
     reserveRoom("7890", "20160907", 3, "00013", "QB"); 
     reserveRoom("7890", "20160909", 3, "00014", "KB"); 
     reserveRoom("7890", "20160905", 1, "00015", "AB"); // fails- unknown room type 
     reserveRoom("1234", "20160905", 1, "00016", "KB"); 
    } 

public void reserveRoom(string h, string d, int n, string c, string t) 
    { 
     ReservationType reservation = new ReservationType(); 

     reservation.hotelId = h; 
     reservation.StartDate = d; 
     reservation.numDays = n; 
     reservation.customerId = c; 
     reservation.roomType = t; 

     // Console.Write(reservation.customerId + ": " + Environment.NewLine); 

     bool result = ReserveRoom(reservation); 


    } 

public bool ReserveRoom(ReservationType reservation) 
    { 
     ReservationType RequestReservation = new ReservationType(); 
     RequestReservation = reservation; //List that contains the test cases. 
     string reservationid = "0001"; 
     int number = int.Parse(reservationid); 
     int count = 0; 

     List<String> DateList = CreateDateList(RequestReservation.StartDate, RequestReservation.numDays); 

      foreach (Inventory inventory in RoomInventory) 
      { 
       if (RequestReservation.hotelId == inventory.HotelId) 
        { 

        if (RequestReservation.roomType == inventory.RoomType) 
        { 
         for (int i = 0; i < DateList.Count; i++) 
         { 
          if (DateList[i] == inventory.Date && inventory.Quantity > 0) 
          { 
           count++; 
           inventory.Quantity--; 
           if (RequestReservation.numDays == count) 
           { 
            RequestReservation.reservationId = "000"+(number + 1).ToString(); 
            RequestReservation.result = ReservationType.ReservationResultType.Success; 
            count = 0; 


           foreach (Hotels h in LHotels) 
            { 
             foreach (Room rm in h.RoomList) 
             { 
              if (RequestReservation.hotelId == h.HotelId && RequestReservation.roomType == rm.RoomType) 
              { 

               RequestReservation.cost = (RequestReservation.numDays * rm.Rate); 
              }            
             } 
            } 

           } // 4th if , numDays == Count 

           else 
           {          
            RequestReservation.reservationId = null; 
            RequestReservation.result = ReservationType.ReservationResultType.RoomNotAvailable;          
           } 

          } //3rd if, DateList check 

         }//Forloop, Datelist 

        }// 2nd if, roomtype check 

       }//first if ,hotelId check 

      number++; 

     } // Inventory List Foreach loop 



       serial = new XmlSerializer(RequestReservation.GetType()); 
       sw = new StreamWriter(ReservationFilename); 
       serial.Serialize(sw, RequestReservation); 
       sw.Close(); 

     return true; 
    }// End of ReserveRoom Method 

Answer 1

Jedes Mal, wenn Sie sw = new StreamWriter(ReservationFilename); die Streamwriter überschreiben alle Daten aufrufen, die zuvor auf die Datei geschrieben wurde. Mit dem Objekt können Sie entscheiden, Ihre Datei im Append Modus zu öffnen.

Denken Sie auch daran Ihre StreamWriter nach der Verwendung zu entsorgen, mit dem using Block:

serial = new XmlSerializer(RequestReservation.GetType()); 

using (FileStream fs = new FileStream(ReservationFilename, FileMode.Append, FileAccess.Write)) 
using (StreamWriter sw = new StreamWriter(fs)) 
{ 
    serial.Serialize(sw, RequestReservation); // Serialize at the end of the file 
} // Closing and disposing FileStream and StreamWriter