XmlAttributes.XmlElements Proprietà

Definizione

Spazio dei nomi:

System.Xml.Serialization

Assembly:

System.Xml.XmlSerializer.dll

Origine:

XmlAttributes.cs

Ottiene un insieme di oggetti che specificano il modo in cui XmlSerializer serializza un campo public o una proprietà di lettura/scrittura come elemento XML.

public:
 property System::Xml::Serialization::XmlElementAttributes ^ XmlElements { System::Xml::Serialization::XmlElementAttributes ^ get(); };

public System.Xml.Serialization.XmlElementAttributes XmlElements { get; }

member this.XmlElements : System.Xml.Serialization.XmlElementAttributes

Public ReadOnly Property XmlElements As XmlElementAttributes

Valore della proprietà

XmlElementAttributes

Un XmlElementAttributes che contiene un insieme di oggetti XmlElementAttribute.

Esempio

L'esempio seguente serializza la Transportation classe , che contiene un singolo campo denominato Vehicles che restituisce un oggetto ArrayList. Nell'esempio vengono applicati due XmlElementAttribute attributi al Vehicles campo . L'esempio crea due XmlElementAttribute oggetti e li aggiunge alla XmlElementAttributes raccolta di un XmlAttributes oggetto . Per consentire alla matrice di accettare tipi di oggetto diversi, l'oggetto XmlAttributes viene aggiunto all'oggetto XmlAttributeOverrides .

#using <System.Xml.dll>
#using <System.dll>

using namespace System;
using namespace System::IO;
using namespace System::Xml::Serialization;
using namespace System::Collections;
using namespace System::Xml;

public ref class Car
{
public:
   String^ Name;
};

public ref class Plane
{
public:
   String^ Name;
};

public ref class Truck
{
public:
   String^ Name;
};

public ref class Train
{
public:
   String^ Name;
};

public ref class Transportation
{
public:

   // Subsequent code overrides these two XmlElementAttributes.

   [XmlElement(Car::typeid),
   XmlElement(Plane::typeid)]
   ArrayList^ Vehicles;
};

// Return an XmlSerializer used for overriding.
XmlSerializer^ CreateOverrider()
{
   // Create the XmlAttributes and XmlAttributeOverrides objects.
   XmlAttributes^ attrs = gcnew XmlAttributes;
   XmlAttributeOverrides^ xOver = gcnew XmlAttributeOverrides;

   /* Create an XmlElementAttribute to override 
      the Vehicles property. */
   XmlElementAttribute^ xElement1 = gcnew XmlElementAttribute( Truck::typeid );

   // Add the XmlElementAttribute to the collection.
   attrs->XmlElements->Add( xElement1 );

   /* Create a second XmlElementAttribute, and 
      add it to the collection. */
   XmlElementAttribute^ xElement2 = gcnew XmlElementAttribute( Train::typeid );
   attrs->XmlElements->Add( xElement2 );

   /* Add the XmlAttributes to the XmlAttributeOverrides,
      specifying the member to override. */
   xOver->Add( Transportation::typeid, "Vehicles", attrs );

   // Create the XmlSerializer, and return it.
   XmlSerializer^ xSer = gcnew XmlSerializer( Transportation::typeid,xOver );
   return xSer;
}

void SerializeObject( String^ filename )
{
   // Create an XmlSerializer instance.
   XmlSerializer^ xSer = CreateOverrider();

   // Create the object and serialize it.
   Transportation^ myTransportation = gcnew Transportation;

   /* Create two new override objects that can be
      inserted into the array. */
   myTransportation->Vehicles = gcnew ArrayList;
   Truck^ myTruck = gcnew Truck;
   myTruck->Name = "MyTruck";
   Train^ myTrain = gcnew Train;
   myTrain->Name = "MyTrain";
   myTransportation->Vehicles->Add( myTruck );
   myTransportation->Vehicles->Add( myTrain );
   TextWriter^ writer = gcnew StreamWriter( filename );
   xSer->Serialize( writer, myTransportation );
}

int main()
{
   SerializeObject( "OverrideElement.xml" );
}

using System;
using System.IO;
using System.Xml.Serialization;
using System.Collections;
using System.Xml;

public class Transportation
{
   // Subsequent code overrides these two XmlElementAttributes.
   [XmlElement(typeof(Car)),
   XmlElement(typeof(Plane))]
   public ArrayList Vehicles;
}

public class Car
{
   public string Name;
}

public class Plane
{
   public string Name;
}
public class Truck
{
   public string Name;
}
public class Train
{
   public string Name;
}

public class Test
{
   public static void Main()
   {
      Test t = new Test();
      t.SerializeObject("OverrideElement.xml");
   }

   // Return an XmlSerializer used for overriding.
   public XmlSerializer CreateOverrider()
   {
      // Create the XmlAttributes and XmlAttributeOverrides objects.
      XmlAttributes attrs = new XmlAttributes();

      XmlAttributeOverrides xOver =
      new XmlAttributeOverrides();

      /* Create an XmlElementAttribute to override
      the Vehicles property. */
      XmlElementAttribute xElement1 =
      new XmlElementAttribute(typeof(Truck));
      // Add the XmlElementAttribute to the collection.
      attrs.XmlElements.Add(xElement1);

      /* Create a second XmlElementAttribute, and
      add it to the collection. */
      XmlElementAttribute xElement2 =
      new XmlElementAttribute(typeof(Train));
      attrs.XmlElements.Add(xElement2);

      /* Add the XmlAttributes to the XmlAttributeOverrides,
      specifying the member to override. */
      xOver.Add(typeof(Transportation), "Vehicles", attrs);

      // Create the XmlSerializer, and return it.
      XmlSerializer xSer = new XmlSerializer
      (typeof(Transportation), xOver);
      return xSer;
   }

   public void SerializeObject(string filename)
   {
      // Create an XmlSerializer instance.
      XmlSerializer xSer = CreateOverrider();

      // Create the object and serialize it.
      Transportation myTransportation =
      new Transportation();

      /* Create two new override objects that can be
      inserted into the array. */
      myTransportation.Vehicles = new ArrayList();
      Truck myTruck = new Truck();
      myTruck.Name = "MyTruck";

      Train myTrain = new Train();
      myTrain.Name = "MyTrain";

      myTransportation.Vehicles.Add(myTruck);
      myTransportation.Vehicles.Add(myTrain);

      TextWriter writer = new StreamWriter(filename);
      xSer.Serialize(writer, myTransportation);
   }
}

Imports System.IO
Imports System.Xml.Serialization
Imports System.Collections
Imports System.Xml


Public Class Transportation
    ' Subsequent code overrides these two XmlElementAttributes.
    <XmlElement(GetType(Car)), _
     XmlElement(GetType(Plane))> _
    Public Vehicles As ArrayList
End Class

Public Class Car
    Public Name As String
End Class

Public Class Plane
    Public Name As String
End Class

Public Class Truck
    Public Name As String
End Class

Public Class Train
    Public Name As String
End Class


Public Class Test
    
    Public Shared Sub Main()
        Dim t As New Test()
        t.SerializeObject("OverrideElement.xml")
    End Sub
    
    
    ' Return an XmlSerializer used for overriding.
    Public Function CreateOverrider() As XmlSerializer
        ' Create the XmlAttributes and XmlAttributeOverrides objects.
        Dim attrs As New XmlAttributes()
        
        Dim xOver As New XmlAttributeOverrides()
        
        
        ' Create an XmlElementAttribute to override
        ' the Vehicles property. 
        Dim xElement1 As New XmlElementAttribute(GetType(Truck))
        ' Add the XmlElementAttribute to the collection.
        attrs.XmlElements.Add(xElement1)
        
        ' Create a second XmlElementAttribute, and
        ' add it to the collection. 
        Dim xElement2 As New XmlElementAttribute(GetType(Train))
        attrs.XmlElements.Add(xElement2)
        
        ' Add the XmlAttributes to the XmlAttributeOverrides,
        ' specifying the member to override. 
        xOver.Add(GetType(Transportation), "Vehicles", attrs)
        
        ' Create the XmlSerializer, and return it.
        Dim xSer As New XmlSerializer(GetType(Transportation), xOver)
        Return xSer
    End Function
    
    
    Public Sub SerializeObject(ByVal filename As String)
        ' Create an XmlSerializer instance.
        Dim xSer As XmlSerializer = CreateOverrider()
        
        ' Create the object and serialize it.
        Dim myTransportation As New Transportation()
        
        ' Create two new override objects that can be'
        ' inserted into the array. 
        myTransportation.Vehicles = New ArrayList()
        Dim myTruck As New Truck()
        myTruck.Name = "MyTruck"
        
        Dim myTrain As New Train()
        myTrain.Name = "MyTrain"
        
        myTransportation.Vehicles.Add(myTruck)
        myTransportation.Vehicles.Add(myTrain)
        
        Dim writer As New StreamWriter(filename)
        xSer.Serialize(writer, myTransportation)
    End Sub
End Class

Commenti

Per ogni membro sottoposto a override serializzato come elemento XML, è necessario aggiungere un nuovo XmlElementAttribute elemento a un XmlElementAttributes oggetto chiamando il Add metodo . Per impostazione predefinita, XmlElementAttributes viene creato e assegnato un oggetto alla XmlElements proprietà .