UnreferencedObjectEventHandler Delegato

Definizione

Spazio dei nomi:

System.Xml.Serialization

Assembly:

System.Xml.XmlSerializer.dll

Rappresenta il metodo di gestione dell'evento UnreferencedObject di un oggetto XmlSerializer.

public delegate void UnreferencedObjectEventHandler(System::Object ^ sender, UnreferencedObjectEventArgs ^ e);

public delegate void UnreferencedObjectEventHandler(object? sender, UnreferencedObjectEventArgs e);

type UnreferencedObjectEventHandler = delegate of obj * UnreferencedObjectEventArgs -> unit

Public Delegate Sub UnreferencedObjectEventHandler(sender As Object, e As UnreferencedObjectEventArgs)

Parametri

sender

Object

Origine dell'evento.

e

UnreferencedObjectEventArgs

Oggetto UnreferencedObjectEventArgs che contiene i dati dell'evento.

Esempio

Nell'esempio seguente viene aggiunto un UnreferencedObjectEventHandler oggetto a un oggetto XmlSerializer. L'evento viene gestito dal Serializer_UnreferencedObject metodo . Per eseguire l'esempio, tagliare e incollare il codice XML seguente in un file denominato 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>

Commenti

Quando si crea un UnreferencedObjectEventHandler delegato, si identifica il metodo che gestisce l'evento. Per associare l'evento al gestore eventi in uso, aggiungere all'evento un'istanza del delegato. Il gestore eventi viene chiamato ogni volta che si verifica l'evento, a meno che non venga rimosso il delegato. Per altre informazioni sui delegati del gestore eventi, vedere Gestione e generazione di eventi

L'evento UnreferencedObject si verifica solo quando si chiama il Deserialize metodo .

Metodi di estensione

GetMethodInfo(Delegate)

Ottiene un oggetto che rappresenta il metodo rappresentato dal delegato specificato.