Exception.GetObjectData(SerializationInfo, StreamingContext) Metodo
Definizione
Quando ne viene eseguito l'override in una classe derivata, imposta il controllo SerializationInfo con le informazioni sull'eccezione.When overridden in a derived class, sets the SerializationInfo with information about the exception.
public:
virtual void GetObjectData(System::Runtime::Serialization::SerializationInfo ^ info, System::Runtime::Serialization::StreamingContext context);
public virtual void GetObjectData (System.Runtime.Serialization.SerializationInfo info, System.Runtime.Serialization.StreamingContext context);
[System.Security.SecurityCritical]
public virtual void GetObjectData (System.Runtime.Serialization.SerializationInfo info, System.Runtime.Serialization.StreamingContext context);
abstract member GetObjectData : System.Runtime.Serialization.SerializationInfo * System.Runtime.Serialization.StreamingContext -> unit
override this.GetObjectData : System.Runtime.Serialization.SerializationInfo * System.Runtime.Serialization.StreamingContext -> unit
[<System.Security.SecurityCritical>]
abstract member GetObjectData : System.Runtime.Serialization.SerializationInfo * System.Runtime.Serialization.StreamingContext -> unit
override this.GetObjectData : System.Runtime.Serialization.SerializationInfo * System.Runtime.Serialization.StreamingContext -> unit
Public Overridable Sub GetObjectData (info As SerializationInfo, context As StreamingContext)
Parametri
- info
- SerializationInfo
Oggetto SerializationInfo che contiene i dati oggetto serializzati relativi all'eccezione generata.The SerializationInfo that holds the serialized object data about the exception being thrown.
- context
- StreamingContext
Oggetto StreamingContext contenente le informazioni contestuali sull'origine o sulla destinazione.The StreamingContext that contains contextual information about the source or destination.
Implementazioni
- Attributi
Eccezioni
Il parametro info
è un riferimento Null (Nothing
in Visual Basic).The info
parameter is a null reference (Nothing
in Visual Basic).
Esempio
Nell'esempio di codice seguente viene definita una classe serializzabile derivata Exception
che implementa GetObjectData
, che apporta modifiche minime a due proprietà e quindi chiama la classe base per eseguire la serializzazione.The following code example defines a derived serializable Exception
class that implements GetObjectData
, which makes minor changes to two properties and then calls the base class to perform the serialization. L'esempio impone un errore di divisione per 0 e quindi crea un'istanza dell'eccezione derivata.The example forces a divide-by-0 error and then creates an instance of the derived exception. Il codice serializza l'istanza in un file, deserializza il file in una nuova eccezione, che genera, quindi rileva e Visualizza i dati dell'eccezione.The code serializes the instance to a file, deserializes the file into a new exception, which it throws, and then catches and displays the exception's data.
#using <System.Runtime.Serialization.Formatters.Soap.dll>
using namespace System;
using namespace System::IO;
using namespace System::Runtime::Serialization;
using namespace System::Runtime::Serialization::Formatters::Soap;
// Define a serializable derived exception class.
[Serializable]
ref class SecondLevelException: public Exception, public ISerializable
{
public:
// This public constructor is used by class instantiators.
SecondLevelException( String^ message, Exception^ inner )
: Exception( message, inner )
{
HelpLink = "http://MSDN.Microsoft.com";
Source = "Exception_Class_Samples";
}
protected:
// This protected constructor is used for deserialization.
SecondLevelException( SerializationInfo^ info, StreamingContext context )
: Exception( info, context )
{}
public:
// GetObjectData performs a custom serialization.
[System::Security::Permissions::SecurityPermissionAttribute
(System::Security::Permissions::SecurityAction::LinkDemand,
Flags=System::Security::Permissions::SecurityPermissionFlag::SerializationFormatter)]
virtual void GetObjectData( SerializationInfo^ info, StreamingContext context ) override
{
// Change the case of two properties, and then use the
// method of the base class.
HelpLink = HelpLink->ToLower();
Source = Source->ToUpperInvariant();
Exception::GetObjectData( info, context );
}
};
int main()
{
Console::WriteLine( "This example of the Exception constructor "
"and Exception.GetObjectData\nwith Serialization"
"Info and StreamingContext parameters "
"generates \nthe following output.\n" );
try
{
// This code forces a division by 0 and catches the
// resulting exception.
try
{
int zero = 0;
int ecks = 1 / zero;
}
catch ( Exception^ ex )
{
// Create a new exception to throw again.
SecondLevelException^ newExcept = gcnew SecondLevelException( "Forced a division by 0 and threw "
"another exception.",ex );
Console::WriteLine( "Forced a division by 0, caught the "
"resulting exception, \n"
"and created a derived exception:\n" );
Console::WriteLine( "HelpLink: {0}", newExcept->HelpLink );
Console::WriteLine( "Source: {0}", newExcept->Source );
// This FileStream is used for the serialization.
FileStream^ stream = gcnew FileStream( "NewException.dat",FileMode::Create );
try
{
// Serialize the derived exception.
SoapFormatter^ formatter = gcnew SoapFormatter( nullptr,StreamingContext(StreamingContextStates::File) );
formatter->Serialize( stream, newExcept );
// Rewind the stream and deserialize the
// exception.
stream->Position = 0;
SecondLevelException^ deserExcept = dynamic_cast<SecondLevelException^>(formatter->Deserialize( stream ));
Console::WriteLine( "\nSerialized the exception, and then "
"deserialized the resulting stream "
"into a \nnew exception. "
"The deserialization changed the case "
"of certain properties:\n" );
// Throw the deserialized exception again.
throw deserExcept;
}
catch ( SerializationException^ se )
{
Console::WriteLine( "Failed to serialize: {0}", se->ToString() );
}
finally
{
stream->Close();
}
}
}
catch ( Exception^ ex )
{
Console::WriteLine( "HelpLink: {0}", ex->HelpLink );
Console::WriteLine( "Source: {0}", ex->Source );
Console::WriteLine();
Console::WriteLine( ex->ToString() );
}
}
/*
This example of the Exception constructor and Exception.GetObjectData
with SerializationInfo and StreamingContext parameters generates
the following output.
Forced a division by 0, caught the resulting exception,
and created a derived exception:
HelpLink: http://MSDN.Microsoft.com
Source: Exception_Class_Samples
Serialized the exception, and then deserialized the resulting stream into a
new exception. The deserialization changed the case of certain properties:
HelpLink: http://msdn.microsoft.com
Source: EXCEPTION_CLASS_SAMPLES
SecondLevelException: Forced a division by 0 and threw another exception. ---> S
ystem.DivideByZeroException: Attempted to divide by zero.
at main()
--- End of inner exception stack trace ---
at main()
*/
using System;
using System.IO;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters.Soap;
using System.Security.Permissions;
// Define a serializable derived exception class.
[Serializable()]
class SecondLevelException : Exception, ISerializable
{
// This public constructor is used by class instantiators.
public SecondLevelException( string message, Exception inner ) :
base( message, inner )
{
HelpLink = "http://MSDN.Microsoft.com";
Source = "Exception_Class_Samples";
}
// This protected constructor is used for deserialization.
protected SecondLevelException( SerializationInfo info,
StreamingContext context ) :
base( info, context )
{ }
// GetObjectData performs a custom serialization.
[SecurityPermissionAttribute(SecurityAction.Demand,SerializationFormatter=true)]
public override void GetObjectData( SerializationInfo info,
StreamingContext context )
{
// Change the case of two properties, and then use the
// method of the base class.
HelpLink = HelpLink.ToLower( );
Source = Source.ToUpperInvariant();
base.GetObjectData( info, context );
}
}
class SerializationDemo
{
public static void Main()
{
Console.WriteLine(
"This example of the Exception constructor " +
"and Exception.GetObjectData\nwith Serialization" +
"Info and StreamingContext parameters " +
"generates \nthe following output.\n" );
try
{
// This code forces a division by 0 and catches the
// resulting exception.
try
{
int zero = 0;
int ecks = 1 / zero;
}
catch( Exception ex )
{
// Create a new exception to throw again.
SecondLevelException newExcept =
new SecondLevelException(
"Forced a division by 0 and threw " +
"another exception.", ex );
Console.WriteLine(
"Forced a division by 0, caught the " +
"resulting exception, \n" +
"and created a derived exception:\n" );
Console.WriteLine( "HelpLink: {0}",
newExcept.HelpLink );
Console.WriteLine( "Source: {0}",
newExcept.Source );
// This FileStream is used for the serialization.
FileStream stream =
new FileStream( "NewException.dat",
FileMode.Create );
try
{
// Serialize the derived exception.
SoapFormatter formatter =
new SoapFormatter( null,
new StreamingContext(
StreamingContextStates.File ) );
formatter.Serialize( stream, newExcept );
// Rewind the stream and deserialize the
// exception.
stream.Position = 0;
SecondLevelException deserExcept =
(SecondLevelException)
formatter.Deserialize( stream );
Console.WriteLine(
"\nSerialized the exception, and then " +
"deserialized the resulting stream " +
"into a \nnew exception. " +
"The deserialization changed the case " +
"of certain properties:\n" );
// Throw the deserialized exception again.
throw deserExcept;
}
catch( SerializationException se )
{
Console.WriteLine( "Failed to serialize: {0}",
se.ToString( ) );
}
finally
{
stream.Close( );
}
}
}
catch( Exception ex )
{
Console.WriteLine( "HelpLink: {0}", ex.HelpLink );
Console.WriteLine( "Source: {0}", ex.Source );
Console.WriteLine( );
Console.WriteLine( ex.ToString( ) );
}
}
}
/*
This example displays the following output.
Forced a division by 0, caught the resulting exception,
and created a derived exception:
HelpLink: http://MSDN.Microsoft.com
Source: Exception_Class_Samples
Serialized the exception, and then deserialized the resulting stream into a
new exception. The deserialization changed the case of certain properties:
HelpLink: http://msdn.microsoft.com
Source: EXCEPTION_CLASS_SAMPLES
NDP_UE_CS.SecondLevelException: Forced a division by 0 and threw another except
ion. ---> System.DivideByZeroException: Attempted to divide by zero.
at NDP_UE_CS.SerializationDemo.Main()
--- End of inner exception stack trace ---
at NDP_UE_CS.SerializationDemo.Main()
*/
' If compiling with the Visual Basic compiler (vbc.exe) from the command
' prompt, be sure to add the following switch:
' /reference:System.Runtime.Serialization.Formatters.Soap.dll
Imports System.IO
Imports System.Runtime.Serialization
Imports System.Runtime.Serialization.Formatters.Soap
Imports System.Security.Permissions
' Define a serializable derived exception class.
<Serializable()> _
Class SecondLevelException
Inherits Exception
' This public constructor is used by class instantiators.
Public Sub New( message As String, inner As Exception )
MyBase.New( message, inner )
HelpLink = "http://MSDN.Microsoft.com"
Source = "Exception_Class_Samples"
End Sub
' This protected constructor is used for deserialization.
Protected Sub New( info As SerializationInfo, _
context As StreamingContext )
MyBase.New( info, context )
End Sub
' GetObjectData performs a custom serialization.
<SecurityPermissionAttribute(SecurityAction.Demand, _
SerializationFormatter:=True)> _
Overrides Sub GetObjectData( info As SerializationInfo, _
context As StreamingContext)
' Change the case of two properties, and then use the
' method of the base class.
HelpLink = HelpLink.ToLower()
Source = Source.ToUpperInvariant()
MyBase.GetObjectData(info, context)
End Sub
End Class
Module SerializationDemo
Sub Main()
Console.WriteLine( _
"This example of the Exception constructor " & _
"and Exception.GetObjectData " & vbCrLf & _
"with SerializationInfo and StreamingContext " & _
"parameters generates " & vbCrLf & _
"the following output." & vbCrLf )
' This code forces a division by 0 and catches the
' resulting exception.
Try
Try
Dim zero As Integer = 0
Dim ecks As Integer = 1 \ zero
' Create a new exception to throw again.
Catch ex As Exception
Dim newExcept As New SecondLevelException( _
"Forced a division by 0 and threw " & _
"another exception.", ex )
Console.WriteLine( _
"Forced a division by 0, caught the " & _
"resulting exception, " & vbCrLf & _
"and created a derived exception:" & vbCrLf )
Console.WriteLine( "HelpLink: {0}", _
newExcept.HelpLink )
Console.WriteLine( "Source: {0}", _
newExcept.Source )
' This FileStream is used for the serialization.
Dim stream As New FileStream( _
"NewException.dat", FileMode.Create )
' Serialize the derived exception.
Try
Dim formatter As New SoapFormatter( Nothing, _
New StreamingContext( _
StreamingContextStates.File ) )
formatter.Serialize( stream, newExcept )
' Rewind the stream and deserialize the
' exception.
stream.Position = 0
Dim deserExcept As SecondLevelException = _
CType( formatter.Deserialize( stream ), _
SecondLevelException )
Console.WriteLine( vbCrLf & _
"Serialized the exception, and then " & _
"deserialized the resulting stream " & _
"into a " & vbCrLf & "new exception. " & _
"The deserialization changed the case " & _
"of certain properties:" & vbCrLf )
' Throw the deserialized exception again.
Throw deserExcept
Catch se As SerializationException
Console.WriteLine( "Failed to serialize: {0}", _
se.ToString( ) )
Finally
stream.Close( )
End Try
End Try
Catch ex As Exception
Console.WriteLine( "HelpLink: {0}", ex.HelpLink )
Console.WriteLine( "Source: {0}", ex.Source )
Console.WriteLine( )
Console.WriteLine( ex.ToString( ) )
End Try
End Sub
End Module
' This example displays the following output:
'
' Forced a division by 0, caught the resulting exception,
' and created a derived exception:
'
' HelpLink: http://MSDN.Microsoft.com
' Source: Exception_Class_Samples
'
' Serialized the exception, and then deserialized the resulting stream into a
' new exception. The deserialization changed the case of certain properties:
'
' HelpLink: http://msdn.microsoft.com
' Source: EXCEPTION_CLASS_SAMPLES
'
' NDP_UE_VB.SecondLevelException: Forced a division by 0 and threw another exce
' ption. ---> System.DivideByZeroException: Attempted to divide by zero.
' at NDP_UE_VB.SerializationDemo.Main()
' --- End of inner exception stack trace ---
' at NDP_UE_VB.SerializationDemo.Main()
Commenti
GetObjectData
imposta l'oggetto SerializationInfo con tutti i dati dell'oggetto dell'eccezione di destinazione della serializzazione.GetObjectData
sets a SerializationInfo with all the exception object data targeted for serialization. Durante la deserializzazione, l'eccezione viene ricostruita da SerializationInfo
trasmesso tramite il flusso.During deserialization, the exception is reconstituted from the SerializationInfo
transmitted over the stream.