XmlAttributes.XmlArrayItems 属性

定义

命名空间:

System.Xml.Serialization

程序集:

System.Xml.XmlSerializer.dll

程序集:

System.Xml.dll

程序集:

netstandard.dll

获取或设置一个对象集合，该集合指定 XmlSerializer 序列化插入数组（由公共字段或读/写属性返回）的项的方式。

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

属性值

XmlArrayItemAttributes

XmlArrayItemAttributes 对象，它包含 XmlArrayItemAttribute 对象的集合。

示例

以下示例序列化一个类，该类包含一个名为返回对象数组的字段 Members 。 创建两 XmlArrayItemAttribute 个对象以允许字段接受派生自命名 Member基类的对象。 每个对象都通过属性添加到XmlAttributesXmlArrayItems其中。

#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:
   array<Member^>^Members;
};

public ref class NewMember: public Member
{
public:
   int MemberID;
};

public ref class RetiredMember: public NewMember
{
public:
   DateTime RetireDate;
};

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

   // Add an override for the XmlArrayItem.    
   XmlArrayItemAttribute^ xArrayItem = gcnew XmlArrayItemAttribute( NewMember::typeid );
   xArrayItem->Namespace = "http://www.cpandl.com";
   xAttrs->XmlArrayItems->Add( xArrayItem );

   // Add a second override.
   XmlArrayItemAttribute^ xArrayItem2 = gcnew XmlArrayItemAttribute( RetiredMember::typeid );
   xArrayItem2->Namespace = "http://www.cpandl.com";
   xAttrs->XmlArrayItems->Add( xArrayItem2 );

   // Add all overrides to XmlAttribueOverrides object.
   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.
   NewMember^ m = gcnew NewMember;
   m->MemberName = "Paul";
   m->MemberID = 2;

   // Create a second member.
   RetiredMember^ m2 = gcnew RetiredMember;
   m2->MemberName = "Renaldo";
   m2->MemberID = 23;
   m2->RetireDate = DateTime(2000,10,10);
   array<Member^>^temp = {m,m2};
   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( "OverrideArrayItem.xml" );
   DeserializeObject( "OverrideArrayItem.xml" );
}

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

注解

该 XmlArrayItems 属性允许指定可插入公共字段或公共读/写属性返回的数组的派生类型。 对于希望字段或属性接受的每个新类型，请创建一个 XmlArrayItemAttribute 对象并将其 Add 传递给 XmlArrayItemAttributes 属性返回 XmlArrayItems) 。 (新类型必须派生自字段或 property 已接受的类型。) Add XmlAttributes 对象到对象 XmlAttributeOverrides ，并指定包含字段或属性的对象的类型以及字段或属性的名称。 在调用或方法之前使用XmlAttributeOverrides对象构造对象XmlSerializer。Deserialize Serialize