XmlAttributes.XmlElements 属性

定义

命名空间:

System.Xml.Serialization

程序集:

System.Xml.XmlSerializer.dll

Source:

XmlAttributes.cs

获取一个对象集合，该集合指定 XmlSerializer 将公共字段或读/写属性串行化为 XML 元素的方式。

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

属性值

XmlElementAttributes

包含一个 XmlElementAttributes 对象集合的 XmlElementAttribute。

示例

下面的示例序列化 Transportation 类，该类包含一个名为 Vehicles 的字段，该 ArrayList字段返回 。 该示例将两 XmlElementAttribute 个属性应用于 Vehicles 字段。 该示例创建两 XmlElementAttribute 个 对象，并将其添加到 XmlElementAttributes 对象的 XmlAttributes 集合中。 若要允许数组接受不同的对象类型，请将 XmlAttributes 对象添加到 XmlAttributeOverrides 对象。

#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

注解

对于序列化为 XML 元素的每个重写成员，必须通过调用 Add 方法向 XmlElementAttributes 添加一个新的 XmlElementAttribute 。 默认情况下，创建对象 XmlElementAttributes 并将其分配给 属性 XmlElements 。