Exception.GetObjectData(SerializationInfo, StreamingContext) Metod
Definition
Viktigt
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När åsidosättas i en härledd klass anger du SerializationInfo med information om undantaget.
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)
Parametrar
- info
- SerializationInfo
Det SerializationInfo som innehåller serialiserade objektdata om undantaget som genereras.
- context
- StreamingContext
Som StreamingContext innehåller kontextuell information om källan eller målet.
Implementeringar
- Attribut
Undantag
Parametern info är en nullreferens (Nothing i Visual Basic).
Exempel
I följande kodexempel definieras en härledd serialiserbar Exception klass som implementerar GetObjectData, som gör mindre ändringar i två egenskaper och sedan anropar basklassen för att utföra serialiseringen. Exemplet tvingar fram ett divide-by-0-fel och skapar sedan en instans av det härledda undantaget. Koden serialiserar instansen till en fil, deserialiserar filen till ett nytt undantag som den genererar och fångar sedan och visar undantagets data.
using System;
using System.IO;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters.Soap;
// 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.
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()
*/
open System
open System.IO
open System.Runtime.Serialization
open System.Runtime.Serialization.Formatters.Soap
open System.Security.Permissions
// Define a serializable derived exception class.
[<Serializable>]
type SecondLevelException =
inherit Exception
interface ISerializable with
// GetObjectData performs a custom serialization.
member this.GetObjectData(info: SerializationInfo, context: StreamingContext) =
// Change the case of two properties, and then use the
// method of the base class.
this.HelpLink <- this.HelpLink.ToLower()
this.Source <- this.Source.ToUpperInvariant()
base.GetObjectData( info, context )
// This public constructor is used by class instantiators.
new (message: string, inner: Exception) as this =
{ inherit Exception(message, inner) }
then
this.HelpLink <- "http://MSDN.Microsoft.com"
this.Source <- "Exception_Class_Samples"
// This protected constructor is used for deserialization.
new (info: SerializationInfo, context: StreamingContext) =
{ inherit Exception(info, context) }
printfn
"""This example of the Exception constructor and Exception.GetObjectData
with SerializationInfo and StreamingContext parameters generates
the following output.
"""
try
// This code forces a division by 0 and catches the
// resulting exception.
try
let zero = 0
let ecks = 1 / zero
()
with ex ->
// Create a new exception to throw again.
let newExcept = SecondLevelException("Forced a division by 0 and threw another exception.", ex)
printfn "Forced a division by 0, caught the resulting exception, \nand created a derived exception:\n"
printfn $"HelpLink: {newExcept.HelpLink}"
printfn $"Source: {newExcept.Source}"
// This FileStream is used for the serialization.
use stream = new FileStream("NewException.dat", FileMode.Create)
try
// Serialize the derived exception.
let formatter = SoapFormatter(null, StreamingContext StreamingContextStates.File)
formatter.Serialize(stream, newExcept)
// Rewind the stream and deserialize the
// exception.
stream.Position <- 0L
let deserExcept = formatter.Deserialize stream :?> SecondLevelException
printfn
"""
Serialized the exception, and then deserialized the resulting stream into a
new exception. The deserialization changed the case of certain properties:
"""
// Throw the deserialized exception again.
raise deserExcept
with :? SerializationException as se ->
printfn $"Failed to serialize: {se}"
with ex ->
printfn $"HelpLink: {ex.HelpLink}"
printfn $"Source: {ex.Source}"
printfn $"\n{ex}"
// This example displays the following output.
// Forced a division by 0, caught the resulting exception,
// and created a derived exception:
//
// HelpLink: http://MSDN.Microsoft.com
// Source: Exception_Class_Samples
//
// Serialized the exception, and then deserialized the resulting stream into a
// new exception. The deserialization changed the case of certain properties:
//
// HelpLink: http://msdn.microsoft.com
// Source: EXCEPTION_CLASS_SAMPLES
//
// NDP_UE_FS_3+SecondLevelException: Forced a division by 0 and threw another except
// ion. ---> System.DivideByZeroException: Attempted to divide by zero.
// at <StartupCode$fs>.$NDP_UE_FS_3.main@()
// --- End of inner exception stack trace ---
// at <StartupCode$fs>.$NDP_UE_FS_3.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()
Kommentarer
GetObjectData anger en SerializationInfo med alla undantagsobjektdata som är avsedda för serialisering. Under deserialiseringen återskapas undantaget från det SerializationInfo som överförs via strömmen.