XmlAttributes.XmlArrayItems Egenskap

Definition

Hämtar eller anger en samling objekt som anger hur serialiserar objekt som XmlSerializer infogats i en matris som returneras av ett offentligt fält eller en läs-/skrivegenskap.

public:
 property System::Xml::Serialization::XmlArrayItemAttributes ^ XmlArrayItems { System::Xml::Serialization::XmlArrayItemAttributes ^ get(); };
public System.Xml.Serialization.XmlArrayItemAttributes XmlArrayItems { get; }
member this.XmlArrayItems : System.Xml.Serialization.XmlArrayItemAttributes
Public ReadOnly Property XmlArrayItems As XmlArrayItemAttributes

Egenskapsvärde

Ett XmlArrayItemAttributes objekt som innehåller en samling XmlArrayItemAttribute objekt.

Exempel

I följande exempel serialiseras en klass som innehåller ett fält med namnet Members som returnerar en matris med objekt. Två XmlArrayItemAttribute objekt skapas för att tillåta att fältet accepterar objekt som härleds från basklassen med namnet Member. Varje objekt läggs till via XmlAttributesXmlArrayItems egenskapen .

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

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

public class Member
{
    public string MemberName;
}

public class NewMember:Member
{
    public int MemberID;
}

public class RetiredMember:NewMember
{
    public DateTime RetireDate;
}

public class Run
{
   public static void Main()
   {
      Run test = new Run();
      test.SerializeObject("OverrideArrayItem.xml");
      test.DeserializeObject("OverrideArrayItem.xml");
   }

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

      // Add an override for the XmlArrayItem.
      XmlArrayItemAttribute xArrayItem =
      new XmlArrayItemAttribute(typeof(NewMember));
      xArrayItem.Namespace = "http://www.cpandl.com";
      xAttrs.XmlArrayItems.Add(xArrayItem);

      // Add a second override.
      XmlArrayItemAttribute xArrayItem2 =
      new XmlArrayItemAttribute(typeof(RetiredMember));
      xArrayItem2.Namespace = "http://www.cpandl.com";
      xAttrs.XmlArrayItems.Add(xArrayItem2);

      // Add all overrides to XmlAttribueOverrides object.
      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.
      NewMember m = new NewMember();
      m.MemberName = "Paul";
      m.MemberID = 2;

      // Create a second member.
      RetiredMember m2 = new RetiredMember();
      m2.MemberName = "Renaldo";
      m2.MemberID = 23;
      m2.RetireDate = new DateTime(2000, 10,10);

      myGroup.Members = new Member[2] {m, m2};

      // 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
    Public Members() As Member
End Class

Public Class Member
    Public MemberName As String
End Class

Public Class NewMember
    Inherits Member
    Public MemberID As Integer
End Class

Public Class RetiredMember
    Inherits NewMember
    Public RetireDate As DateTime
End Class


Public Class Run
    
    Public Shared Sub Main()
        Dim test As New Run()
        test.SerializeObject("OverrideArrayItem.xml")
        test.DeserializeObject("OverrideArrayItem.xml")
    End Sub    
    
    ' Return an XmlSerializer used for overriding. 
    Public Function CreateOverrider() As XmlSerializer
        ' Create XmlAttributeOverrides and XmlAttributes objects.
        Dim xOver As New XmlAttributeOverrides()
        Dim xAttrs As New XmlAttributes()
        
        ' Add an override for the XmlArrayItem.    
        Dim xArrayItem As New XmlArrayItemAttribute(GetType(NewMember))
        xArrayItem.Namespace = "http://www.cpandl.com"
        xAttrs.XmlArrayItems.Add(xArrayItem)
        
        ' Add a second override.
        Dim xArrayItem2 As New XmlArrayItemAttribute(GetType(RetiredMember))
        xArrayItem2.Namespace = "http://www.cpandl.com"
        xAttrs.XmlArrayItems.Add(xArrayItem2)
        
        ' Add all overrides to XmlAttribueOverrides object.
        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 NewMember()
        m.MemberName = "Paul"
        m.MemberID = 2
        
        ' Create a second member.
        Dim m2 As New RetiredMember()
        m2.MemberName = "Renaldo"
        m2.MemberID = 23
        m2.RetireDate = New DateTime(2000, 10, 10)
        
        myGroup.Members = New Member(1) {m, m2}
        
        ' 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

Kommentarer

Med XmlArrayItems egenskapen kan du ange de härledda typer som kan infogas i en matris som returneras av ett offentligt fält eller en offentlig läs-/skrivegenskap. För varje ny typ som du vill att fältet eller egenskapen ska acceptera skapar du ett XmlArrayItemAttribute objekt och Add det till ) XmlArrayItemAttributessom returneras av XmlArrayItems egenskapen. (Den nya typen måste härledas från den typ som redan godkänts av fältet eller egenskapen.) Add objektet XmlAttributes till ett XmlAttributeOverrides objekt och ange typen av objekt som innehåller fältet eller egenskapen och namnet på fältet eller egenskapen. Konstruera ett XmlSerializer med - XmlAttributeOverrides objektet innan du anropar Serialize eller Deserialize metoden.

Gäller för