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XmlAttributes.XmlArray Property

Definition

Gets or sets an object that specifies how the XmlSerializer serializes a public field or read/write property that returns an array.

public:
 property System::Xml::Serialization::XmlArrayAttribute ^ XmlArray { System::Xml::Serialization::XmlArrayAttribute ^ get(); void set(System::Xml::Serialization::XmlArrayAttribute ^ value); };
public System.Xml.Serialization.XmlArrayAttribute XmlArray { get; set; }
public System.Xml.Serialization.XmlArrayAttribute? XmlArray { get; set; }
member this.XmlArray : System.Xml.Serialization.XmlArrayAttribute with get, set
Public Property XmlArray As XmlArrayAttribute

Property Value

An XmlArrayAttribute that specifies how the XmlSerializer serializes a public field or read/write property that returns an array.

Examples

The following example serializes a class that contains a field named Members that returns an array of objects. The XmlArrayAttribute is used to override the serialization of the field, and rename the element name to Staff.

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

using namespace System;
using namespace System::IO;
using namespace System::Xml;
using namespace System::Xml::Serialization;
public ref class Member
{
public:
   String^ MemberName;
};


// This is the class that will be serialized.
public ref class Group
{
public:

   // This field will be overridden.
   array<Member^>^Members;
};


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

   // Add an override for the XmlArray.    
   XmlArrayAttribute^ xArray = gcnew XmlArrayAttribute( "Staff" );
   xArray->Namespace = "http://www.cpandl.com";
   xAttrs->XmlArray = xArray;
   xOver->Add( Group::typeid, "Members", xAttrs );

   // Create the XmlSerializer and return it.
   return gcnew XmlSerializer( Group::typeid,xOver );
}

void SerializeObject( String^ filename )
{
   // Create an instance of the XmlSerializer class.
   XmlSerializer^ mySerializer = CreateOverrider();

   // Writing the file requires a TextWriter.
   TextWriter^ writer = gcnew StreamWriter( filename );

   // Create an instance of the class that will be serialized.
   Group^ myGroup = gcnew Group;

   // Set the object properties.
   Member^ m = gcnew Member;
   m->MemberName = "Paul";
   array<Member^>^temp = {m};
   myGroup->Members = temp;

   // Serialize the class, and close the TextWriter.
   mySerializer->Serialize( writer, myGroup );
   writer->Close();
}

void DeserializeObject( String^ filename )
{
   XmlSerializer^ mySerializer = CreateOverrider();
   FileStream^ fs = gcnew FileStream( filename,FileMode::Open );
   Group^ myGroup = dynamic_cast<Group^>(mySerializer->Deserialize( fs ));
   System::Collections::IEnumerator^ myEnum = myGroup->Members->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Member^ m = safe_cast<Member^>(myEnum->Current);
      Console::WriteLine( m->MemberName );
   }
}

int main()
{
   SerializeObject( "OverrideArray.xml" );
   DeserializeObject( "OverrideArray.xml" );
}
using System;
using System.IO;
using System.Xml;
using System.Xml.Serialization;

// This is the class that will be serialized.
public class Group
{
   // This field will be overridden.
   public Member [] Members;
}

public class Member
{
   public string MemberName;
}

public class Run
{
   public static void Main()
   {
      Run test = new Run();
      test.SerializeObject("OverrideArray.xml");
      test.DeserializeObject("OverrideArray.xml");
   }
   // Return an XmlSerializer used for overriding.
   public XmlSerializer CreateOverrider()
   {
      // Creating XmlAttributeOverrides and XmlAttributes objects.
      XmlAttributeOverrides xOver = new XmlAttributeOverrides();
      XmlAttributes xAttrs = new XmlAttributes();

      // Add an override for the XmlArray.
      XmlArrayAttribute xArray = new XmlArrayAttribute("Staff");
      xArray.Namespace = "http://www.cpandl.com";
      xAttrs.XmlArray = xArray;
      xOver.Add(typeof(Group), "Members", xAttrs);

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

   public void SerializeObject(string filename)
   {
      // Create an instance of the XmlSerializer class.
      XmlSerializer mySerializer =  CreateOverrider();
      // Writing the file requires a TextWriter.
      TextWriter writer = new StreamWriter(filename);

      // Create an instance of the class that will be serialized.
      Group myGroup = new Group();

      // Set the object properties.
      Member m = new Member();
      m.MemberName = "Paul";
      myGroup.Members = new Member[1] {m};

      // Serialize the class, and close the TextWriter.
      mySerializer.Serialize(writer, myGroup);
      writer.Close();
   }

   public void DeserializeObject(string filename)
   {
      XmlSerializer mySerializer = CreateOverrider();
      FileStream fs = new FileStream(filename, FileMode.Open);
      Group myGroup = (Group)
      mySerializer.Deserialize(fs);
      foreach(Member m in myGroup.Members)
      {
         Console.WriteLine(m.MemberName);
      }
   }
}
Imports System.IO
Imports System.Xml
Imports System.Xml.Serialization


' This is the class that will be serialized.
Public Class Group
    ' This field will be overridden.
    Public Members() As Member
End Class

Public Class Member
    Public MemberName As String
End Class

Public Class Run
    
    Public Shared Sub Main()
        Dim test As New Run()
        test.SerializeObject("OverrideArray.xml")
        test.DeserializeObject("OverrideArray.xml")
    End Sub
    
    ' Return an XmlSerializer used for overriding. 
    Public Function CreateOverrider() As XmlSerializer
        ' Creating XmlAttributeOverrides and XmlAttributes objects.
        Dim xOver As New XmlAttributeOverrides()
        Dim xAttrs As New XmlAttributes()
        
        ' Add an override for the XmlArray.    
        Dim xArray As New XmlArrayAttribute("Staff")
        xArray.Namespace = "http://www.cpandl.com"
        xAttrs.XmlArray = xArray
        xOver.Add(GetType(Group), "Members", xAttrs)
        
        ' Create the XmlSerializer and return it.
        Return New XmlSerializer(GetType(Group), xOver)
    End Function
    
    Public Sub SerializeObject(ByVal filename As String)
        ' Create an instance of the XmlSerializer class.
        Dim mySerializer As XmlSerializer = CreateOverrider()
        ' Writing the file requires a TextWriter.
        Dim writer As New StreamWriter(filename)
        
        ' Create an instance of the class that will be serialized.
        Dim myGroup As New Group()
        
        ' Set the object properties.
        Dim m As New Member()
        m.MemberName = "Paul"
        myGroup.Members = New Member(0) {m}
        
        ' Serialize the class, and close the TextWriter.
        mySerializer.Serialize(writer, myGroup)
        writer.Close()
    End Sub    
    
    Public Sub DeserializeObject(ByVal filename As String)
        Dim mySerializer As XmlSerializer = CreateOverrider()
        Dim fs As New FileStream(filename, FileMode.Open)
        Dim myGroup As Group = CType(mySerializer.Deserialize(fs), Group)
        Dim m As Member
        For Each m In  myGroup.Members
            Console.WriteLine(m.MemberName)
        Next m
    End Sub
End Class

Remarks

There are two ways in which a public field or public read/write property that returns an array is serialized by the XmlSerializer: the default serialization, and the controlled serialization.

In the default serialization, no attribute is applied to the member. When serialized, the array is serialized as a nested sequence of XML elements with the XML element name of the nested sequence taken from the member name.

To control the serialization more precisely, apply an XmlArrayAttribute to the field or property. For example, you can change the generated XML element name from the default to a different name by setting the ElementName property to a new value.

The XmlArray property allows you to override the default serialization, as well as the serialization controlled by applying an XmlArrayAttribute to the member. For example, you can change the XML element name generated from the default (the member identifier) to a new value. In addition, if you apply an XmlArrayAttribute to a member, it is overridden by any XmlArrayAttribute that is assigned to the XmlArray property.

Applies to