XmlSerializer.UnreferencedObject Událost

  • Reference

Definice

Obor názvů:
System.Xml.Serialization
Sestavení:
System.Xml.XmlSerializer.dll
Sestavení:
System.Xml.dll
Sestavení:
netstandard.dll
Zdroj:
XmlSerializer.cs
Zdroj:
XmlSerializer.cs
Zdroj:
XmlSerializer.cs

Vyskytuje se při deserializaci xml zakódované SOAP datového proudu, když XmlSerializer narazí na rozpoznaný typ, který není použit nebo je neodkazován.

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

Event Type

UnreferencedObjectEventHandler

Příklady

Následující příklad přidá do objektu UnreferencedObjectEventHandlerXmlSerializer. Událost zpracovává Serializer``_``UnreferencedObject metoda . Příklad spustíte tak, že vyjmete a vložíte následující kód XML do souboru s názvem "UnrefObj.xml".

<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>

Poznámky

Událost UnreferencedObject nastane pouze v případě, že XmlSerializer se používá k deserializaci dokumentu XML, který obsahuje zprávu SOAP, která odpovídá oddílu 5 dokumentu World Wide Web Consortium, PROTOKOL SOAP (Simple Object Access Protocol) 1.1.

Dokumenty, které odpovídají oddílu 5, jsou ve speciálním formátu. Přinejmenším takový dokument obsahuje hlavní text zprávy SOAP. Místo toho, aby se všechny typy definovaly přímo v dokumentu, je však možné některé definice typů kódovat jako odkazy na prvky nejvyšší úrovně v dokumentu. Proto pro každý prvek nalezený v hlavním těle, který je odkazem, musí existovat odpovídající prvek, který obsahuje definici typu. Chcete-li korelovat odkazující prvek a definici typu, definice typu má id atribut nastavený na jedinečné ID řetězce a odkazující element má href atribut, který odkazuje na stejné ID.

<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>

Událost UnreferencedObject nastane, když se v dokumentu najde definice typu, ale žádný parametr v hlavním textu na ni odkazuje. Když dojde k události, můžete načíst typ XML neodkazovaného objektu prozkoumáním UnreferencedObject vlastnosti UnreferencedObjectEventArgs třídy . ID XML objektu je vráceno UnreferencedId vlastností .

Událost UnreferencedObject by neměla být zaměňována s událostmi UnknownElement a UnknownNode , ke kterým dochází, když neexistuje žádný člen třídy, který odpovídá typu xml uzlu nebo elementu.

Platí pro

Viz také