XmlSerializer.UnreferencedObject 事件

定义

在反序列化 SOAP 编码的 XML 流的过程中发生,此时 XmlSerializer 遇到未使用(或未引用)的识别类型。

public:
 event System::Xml::Serialization::UnreferencedObjectEventHandler ^ UnreferencedObject;
public event System.Xml.Serialization.UnreferencedObjectEventHandler UnreferencedObject;
member this.UnreferencedObject : System.Xml.Serialization.UnreferencedObjectEventHandler 
Public Custom Event UnreferencedObject As UnreferencedObjectEventHandler 

事件类型

示例

以下示例将 添加到 UnreferencedObjectEventHandlerXmlSerializer。 事件由 Serializer``_``UnreferencedObject 方法处理。 若要运行该示例,请将以下 XML 剪切并粘贴到名为“UnrefObj.xml”的文件中。

<wrapper>
  <Group xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" id="id1" n1:GroupName=".NET" xmlns:n1="http://www.cpandl.com">
   </Group>
<Vehicle id="id2" n1:type="Vehicle" xmlns:n1="http://www.w3.org/2001/XMLSchema-instance">
    <licenseNumber xmlns:q1="http://www.w3.org/2001/XMLSchema" n1:type="q1:string">ABCD</licenseNumber>
  </Vehicle>
<Vehicle id="id3" n1:type="Vehicle" xmlns:n1="http://www.w3.org/2001/XMLSchema-instance">
    <licenseNumber xmlns:q1="http://www.w3.org/2001/XMLSchema" n1:type="q1:string">1234</licenseNumber>
  </Vehicle>
</wrapper>
#using <System.Xml.dll>
#using <System.dll>

using namespace System;
using namespace System::IO;
using namespace System::Text;
using namespace System::Xml;
using namespace System::Xml::Serialization;
using namespace System::Xml::Schema;

ref class Vehicle;

[SoapInclude(Vehicle::typeid)]
public ref class Vehicle
{
public:
   String^ licenseNumber;
};


// You must use the SoapIncludeAttribute to inform the XmlSerializer
// that the Vehicle type should be recognized when deserializing.

[SoapInclude(Vehicle::typeid)]
public ref class Group
{
public:
   String^ GroupName;
   Vehicle^ GroupVehicle;
};

public ref class Run
{
public:
   void DeserializeObject( String^ filename )
   {
      // Create an instance of the XmlSerializer class.
      XmlTypeMapping^ myMapping = ((gcnew SoapReflectionImporter)->ImportTypeMapping( Group::typeid ));
      XmlSerializer^ mySerializer = gcnew XmlSerializer( myMapping );
      mySerializer->UnreferencedObject += gcnew UnreferencedObjectEventHandler( this, &Run::Serializer_UnreferencedObject );
      
      // Reading the file requires an  XmlTextReader.
      XmlTextReader^ reader = gcnew XmlTextReader( filename );
      reader->ReadStartElement();
      
      // Deserialize and cast the object.
      Group^ myGroup;
      myGroup = dynamic_cast<Group^>(mySerializer->Deserialize( reader ));
      reader->ReadEndElement();
      reader->Close();
   }

private:
   void Serializer_UnreferencedObject( Object^ /*sender*/, UnreferencedObjectEventArgs^ e )
   {
      Console::WriteLine( "UnreferencedObject:" );
      Console::WriteLine( "ID: {0}", e->UnreferencedId );
      Console::WriteLine( "UnreferencedObject: {0}", e->UnreferencedObject );
      Vehicle^ myVehicle = dynamic_cast<Vehicle^>(e->UnreferencedObject);
      Console::WriteLine( "License: {0}", myVehicle->licenseNumber );
   }
};

int main()
{
   Run^ test = gcnew Run;
   test->DeserializeObject( "UnrefObj.xml" );
}

// The file named S"UnrefObj.xml" should contain this XML:
//  <Group xmlns:xsi=S"http://www.w3.org/2001/XMLSchema-instance" 
//xmlns:xsd=S"http://www.w3.org/2001/XMLSchema" id=S"id1" 
//n1:GroupName=S".NET" xmlns:n1=S"http://www.cpandl.com">
//<Vehicle id=S"id2" n1:type=S"Vehicle" 
//xmlns:n1=S"http://www.w3.org/2001/XMLSchema-instance">
//   <licenseNumber xmlns:q1=S"http://www.w3.org/2001/XMLSchema" 
//n1:type=S"q1:String*">ABCD</licenseNumber>
//<Vehicle id=S"id3" n1:type=S"Vehicle" 
//xmlns:n1=S"http://www.w3.org/2001/XMLSchema-instance">
//    <licenseNumber xmlns:q1=S"http://www.w3.org/2001/XMLSchema" 
//n1:type=S"q1:String*">1234</licenseNumber>
using System;
using System.IO;
using System.Text;
using System.Xml;
using System.Xml.Serialization;
using System.Xml.Schema;

// You must use the SoapIncludeAttribute to inform the XmlSerializer
// that the Vehicle type should be recognized when deserializing.
[SoapInclude(typeof(Vehicle))]
public class Group
{
   public string GroupName;
   public Vehicle GroupVehicle;
}
 [SoapInclude(typeof(Vehicle))]
public class Vehicle
{
   public string licenseNumber;
}

public class Run
{
   public static void Main()
   {
      Run test = new Run();
      test.DeserializeObject("UnrefObj.xml");
   }
   
   public void DeserializeObject(string filename)
   {
      // Create an instance of the XmlSerializer class.
      XmlTypeMapping myMapping = 
      (new SoapReflectionImporter().ImportTypeMapping(
      typeof(Group)));
      XmlSerializer mySerializer =  
      new XmlSerializer(myMapping);
 
      mySerializer.UnreferencedObject += 
      new UnreferencedObjectEventHandler
      (Serializer_UnreferencedObject);

      // Reading the file requires an  XmlTextReader.
      XmlTextReader reader= 
      new XmlTextReader(filename);
      reader.ReadStartElement();

      // Deserialize and cast the object.
      Group myGroup; 
      myGroup = (Group) mySerializer.Deserialize(reader);
      reader.ReadEndElement();
      reader.Close();
   }

   private void Serializer_UnreferencedObject
   (object sender, UnreferencedObjectEventArgs e){
      Console.WriteLine("UnreferencedObject:");
      Console.WriteLine("ID: " + e.UnreferencedId);
      Console.WriteLine("UnreferencedObject: " + e.UnreferencedObject);
      Vehicle myVehicle = (Vehicle) e.UnreferencedObject;
      Console.WriteLine("License: " + myVehicle.licenseNumber);
   }
}

// The file named "UnrefObj.xml" should contain this XML:


//  <Group xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
//xmlns:xsd="http://www.w3.org/2001/XMLSchema" id="id1" 
//n1:GroupName=".NET" xmlns:n1="http://www.cpandl.com">

//<Vehicle id="id2" n1:type="Vehicle" 
//xmlns:n1="http://www.w3.org/2001/XMLSchema-instance">
//   <licenseNumber xmlns:q1="http://www.w3.org/2001/XMLSchema" 
//n1:type="q1:string">ABCD</licenseNumber>

//<Vehicle id="id3" n1:type="Vehicle" 
//xmlns:n1="http://www.w3.org/2001/XMLSchema-instance">
//    <licenseNumber xmlns:q1="http://www.w3.org/2001/XMLSchema" 
//n1:type="q1:string">1234</licenseNumber>
Imports System.IO
Imports System.Text
Imports System.Xml
Imports System.Xml.Serialization
Imports System.Xml.Schema

' You must use the SoapIncludeAttribute to inform the XmlSerializer
' that the Vehicle type should be recognized when deserializing.
<SoapInclude(GetType(Vehicle))> _
Public Class Group
    Public GroupName As String 
   public GroupVehicle As Vehicle 
End Class

Public Class Vehicle
   Public licenseNumber As String 
End Class

 
Public Class Run
   Shared Sub Main()
      Dim test As Run = new Run()
      test.DeserializeObject("UnrefObj.xml")
   End Sub
   
   Public Sub DeserializeObject(filename As String)
      ' Create an instance of the XmlSerializer class.
      Dim myMapping As XmlTypeMapping = _
      (new SoapReflectionImporter().ImportTypeMapping _
      (GetType(Group)))
      Dim mySerializer As XmlSerializer =  _
      new XmlSerializer(myMapping)

      AddHandler mySerializer.UnreferencedObject, _
      AddressOf Serializer_UnreferencedObject

      ' Reading the file requires an  XmlTextReader.
      Dim reader As XmlTextReader = _
      new XmlTextReader(filename)
      reader.ReadStartElement()

      ' Deserialize and cast the object.
      Dim myGroup As Group  
      myGroup = CType( mySerializer.Deserialize(reader), Group)
      reader.ReadEndElement()
      reader.Close()
   End Sub
   
   Private Sub Serializer_UnreferencedObject _
   (sender As object , e As UnreferencedObjectEventArgs)
      Console.WriteLine("UnreferencedObject:")
      Console.WriteLine("ID: " + e.UnreferencedId)
      Console.WriteLine("UnreferencedObject: " + e.UnreferencedObject)
      Dim myVehicle As Vehicle = CType(e.UnreferencedObject, Vehicle)
      Console.WriteLine("License: " + myVehicle.licenseNumber)
       End Sub
 End Class
 
' The XML document should contain this information:


'  <Group xmlns:xsi="http:'www.w3.org/2001/XMLSchema-instance" 
'xmlns:xsd="http:'www.w3.org/2001/XMLSchema" id="id1" 
'n1:GroupName=".NET" xmlns:n1="http:'www.cpandl.com">

'<Vehicle id="id2" n1:type="Vehicle" 
'xmlns:n1="http:'www.w3.org/2001/XMLSchema-instance">
'    <licenseNumber xmlns:q1="http:'www.w3.org/2001/XMLSchema" 
'n1:type="q1:string">ABCD</licenseNumber>

'<Vehicle id="id3" n1:type="Vehicle" 
'xmlns:n1="http:'www.w3.org/2001/XMLSchema-instance">
'    <licenseNumber xmlns:q1="http:'www.w3.org/2001/XMLSchema" 
'n1:type="q1:string">1234</licenseNumber>

注解

UnreferencedObject仅当 用于反序列化包含符合万维网联合会文档简单对象访问协议 (SOAP) 1.1 部分的 SOAP 消息的 XML 文档时XmlSerializer,才会发生该事件。

符合第 5 节的文档采用特殊格式。 至少,此类文档包含 SOAP 消息的main正文。 但是,某些类型定义可以编码为对文档中顶级元素的引用,而不是在文档中内联定义所有类型。 因此,对于在作为引用的main正文中找到的每个元素,都必须有一个包含类型定义的相应元素。 为了关联引用元素和类型定义,类型定义将属性 id 设置为唯一的字符串 ID,引用元素具有 href 引用相同 ID 的属性。

<Group xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" id="id1" n1:GroupName=".NET" GroupNumber="ZDI=" CreationDate="2002-05-02" xmlns:n1="http:'www.cpandl.com">
    <PosInt xsi:type="xsd:nonNegativeInteger">10000</PosInt>
    <GroupVehicle href="#id2" />
  </Group>
  <Vehicle id="id2" n1:type="Vehicle" xmlns:n1="http://www.w3.org/2001/XMLSchema-instance">
    <licenseNumber xmlns:q1="http://www.w3.org/2001/XMLSchema" n1:type="q1:string">1234</licenseNumber>
  </Vehicle>

UnreferencedObject在文档中找到类型定义,但main正文中没有参数引用该类型定义时,会发生该事件。 事件发生时,可以通过检查 UnreferencedObject 类的 属性 UnreferencedObjectEventArgs 来检索未引用对象的 XML 类型。 对象的 XML ID 由 UnreferencedId 属性返回。

不应将 UnreferencedObject 事件与 UnknownElementUnknownNode 事件混淆,当不存在与 XML 节点或元素类型对应的类成员时,会发生这些事件。

适用于

另请参阅