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XmlAttributes.XmlElements Property

Gets or sets a collection of objects that specify how the XmlSerializer serializes a public field or read/write property as an XML element.

[Visual Basic]
Public ReadOnly Property XmlElements As XmlElementAttributes
[C#]
public XmlElementAttributes XmlElements {get;}
[C++]
public: __property XmlElementAttributes* get_XmlElements();
[JScript]
public function get XmlElements() : XmlElementAttributes;

Property Value

An XmlElementAttributes that contains a collection of XmlElementAttribute objects.

Remarks

For each overridden member that is serialized as an XML element, you must add a new XmlElementAttribute to an XmlElementAttributes by calling the Add method. By default, an XmlElementAttributes object is created and assigned to the XmlElements property.

Example

[Visual Basic, C#, C++] The following example serializes the Transportation class, which contains a single field named Vehicles that returns an ArrayList. The example applies two XmlElementAttribute attributes to the Vehicles field. The example creates two XmlElementAttribute objects and adds them to the XmlElementAttributes collection of an XmlAttributes object. To allow the array to accept different object types, the XmlAttributes object is added to the XmlAttributeOverrides object.

[Visual Basic] 
Imports System
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


[C#] 
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);
      
   }
}


[C++] 
#using <mscorlib.dll>
#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 __gc class Car
{
public:
   String* Name;
};

public __gc class Plane
{
public:
   String* Name;
};

public __gc class Truck
{
public:
   String* Name;
};

public __gc class Train
{
public:
   String* Name;
};

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

// Return an XmlSerializer used for overriding.
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), S"Vehicles", attrs);

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

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 = S"MyTruck";

   Train* myTrain = new Train();
   myTrain->Name = S"MyTrain";

   myTransportation->Vehicles->Add(myTruck);
   myTransportation->Vehicles->Add(myTrain);

   TextWriter* writer = new StreamWriter(filename);
   xSer->Serialize(writer, myTransportation);

}

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

[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button Language Filter in the upper-left corner of the page.

Requirements

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family

See Also

XmlAttributes Class | XmlAttributes Members | System.Xml.Serialization Namespace

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