UnreferencedObjectEventHandler Делегат
Определение
Важно!
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Представляет метод, обрабатывающий событие UnreferencedObject класса XmlSerializer.
public delegate void UnreferencedObjectEventHandler(System::Object ^ sender, UnreferencedObjectEventArgs ^ e);
public delegate void UnreferencedObjectEventHandler(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)
Параметры
- sender
- Object
Источник события.
Объект класса UnreferencedObjectEventArgs, содержащий данные события.
Примеры
В следующем примере добавляется в UnreferencedObjectEventHandler .XmlSerializer Событие обрабатывается методом Serializer_UnreferencedObject
. Чтобы выполнить пример, вырезайте и вставьте следующий XML-код в файл с именем 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>
Комментарии
При создании делегата UnreferencedObjectEventHandler определяется метод, обрабатывающий событие. Чтобы связать событие с обработчиком событий, нужно добавить в событие экземпляр делегата. Обработчик событий вызывается всякий раз, когда происходит событие, если делегат не удален. Дополнительные сведения о делегатах обработчика событий см. в разделе Обработка и вызов событий.
Событие UnreferencedObject возникает только при вызове Deserialize метода .
Методы расширения
GetMethodInfo(Delegate) |
Получает объект, представляющий метод, представленный указанным делегатом. |