AppDomainUnloadedException Classe
Definição
A exceção lançada quando há uma tentativa de acessar um domínio de aplicativo descarregado.The exception that is thrown when an attempt is made to access an unloaded application domain.
public ref class AppDomainUnloadedException : SystemException
public class AppDomainUnloadedException : SystemException
[System.Serializable]
public class AppDomainUnloadedException : SystemException
[System.Serializable]
[System.Runtime.InteropServices.ComVisible(true)]
public class AppDomainUnloadedException : SystemException
type AppDomainUnloadedException = class
inherit SystemException
[<System.Serializable>]
type AppDomainUnloadedException = class
inherit SystemException
[<System.Serializable>]
[<System.Runtime.InteropServices.ComVisible(true)>]
type AppDomainUnloadedException = class
inherit SystemException
Public Class AppDomainUnloadedException
Inherits SystemException
- Herança
- Atributos
Exemplos
Esta seção contém dois exemplos de código.This section contains two code examples. O primeiro exemplo demonstra os efeitos de um AppDomainUnloadedException em vários threads e o segundo mostra elementar descarregar domínio do aplicativo.The first example demonstrates the effects of an AppDomainUnloadedException on various threads, and the second shows elementary application domain unloading.
Exemplo 1Example 1
O exemplo de código a seguir define uma TestClass
classe que pode ser empacotado entre limites de domínio de aplicativo e uma Example
classe que contém uma static
(Shared
no Visual Basic) ThreadProc
método.The following code example defines a TestClass
class that can be marshaled across application domain boundaries and an Example
class containing a static
(Shared
in Visual Basic) ThreadProc
method. O ThreadProc
método cria um domínio de aplicativo, cria um TestClass
objeto no domínio e chama um método de TestClass
que descarrega o domínio em execução, fazendo com que um AppDomainUnloadedException.The ThreadProc
method creates an application domain, creates a TestClass
object in the domain, and calls a method of TestClass
that unloads the executing domain, causing an AppDomainUnloadedException.
O TestClass
método é executado sem tratamento de exceções um ThreadPool thread e de um thread comum, demonstrando que a exceção sem tratamento encerra a tarefa ou thread, mas não o aplicativo.The TestClass
method is executed without exception handling from a ThreadPool thread and from an ordinary thread, demonstrating that the unhandled exception terminates the task or thread but not the application. Em seguida, ele é executado com e sem tratamento do thread do aplicativo principal, demonstrando que ele encerra o aplicativo se não forem manipulados de exceção.It is then executed with and without exception handling from the main application thread, demonstrating that it terminates the application if not handled.
using System;
using System.Threading;
using System.Runtime.InteropServices;
public class Example
{
public static void Main()
{
// 1. Queue ThreadProc as a task for a ThreadPool thread.
ThreadPool.QueueUserWorkItem(ThreadProc, " from a ThreadPool thread");
Thread.Sleep(1000);
// 2. Execute ThreadProc on an ordinary thread.
Thread t = new Thread(ThreadProc);
t.Start(" from an ordinary thread");
t.Join();
// 3. Execute ThreadProc on the main thread, with
// exception handling.
try
{
ThreadProc(" from the main application thread (handled)");
}
catch (AppDomainUnloadedException adue)
{
Console.WriteLine("Main thread caught AppDomainUnloadedException: {0}", adue.Message);
}
// 4. Execute ThreadProc on the main thread without
// exception handling.
ThreadProc(" from the main application thread (unhandled)");
Console.WriteLine("Main: This message is never displayed.");
}
private static void ThreadProc(object state)
{
// Create an application domain, and create an instance
// of TestClass in the application domain. The first
// parameter of CreateInstanceAndUnwrap is the name of
// this executable. If you compile the example code using
// any name other than "Sample.exe", you must change the
// parameter appropriately.
AppDomain ad = AppDomain.CreateDomain("TestDomain");
TestClass tc = (TestClass)ad.CreateInstanceAndUnwrap("Sample", "TestClass");
// In the new application domain, execute a method that
// unloads the AppDomain. The unhandled exception this
// causes ends the current thread.
tc.UnloadCurrentDomain(state);
Console.WriteLine("ThreadProc: This message is never displayed.");
}
}
// TestClass derives from MarshalByRefObject, so it can be marshaled
// across application domain boundaries.
//
public class TestClass : MarshalByRefObject
{
public void UnloadCurrentDomain(object state)
{
Console.WriteLine("\nUnloading the current AppDomain{0}.", state);
// Unload the current application domain. This causes
// an AppDomainUnloadedException to be thrown.
//
AppDomain.Unload(AppDomain.CurrentDomain);
}
}
/* This code example produces output similar to the following:
Unloading the current AppDomain from a ThreadPool thread.
Unloading the current AppDomain from an ordinary thread.
Unloading the current AppDomain from the main application thread (handled).
Main thread caught AppDomainUnloadedException: The application domain in which the thread was running has been unloaded.
Unloading the current AppDomain from the main application thread (unhandled).
Unhandled Exception: System.AppDomainUnloadedException: The application domain in which the thread was running has been unloaded.
at TestClass.UnloadCurrentDomain(Object state)
at Example.ThreadProc(Object state)
at Example.Main()
*/
Imports System.Threading
Imports System.Runtime.InteropServices
Public Class Example
Public Shared Sub Main()
' 1. Queue ThreadProc as a task for a ThreadPool thread.
ThreadPool.QueueUserWorkItem(AddressOf ThreadProc, _
" from a ThreadPool thread")
Thread.Sleep(1000)
' 2. Execute ThreadProc on an ordinary thread.
Dim t As New Thread(AddressOf ThreadProc)
t.Start(" from an ordinary thread")
t.Join()
' 3. Execute ThreadProc on the main thread, with
' exception handling.
Try
ThreadProc(" from the main application thread (handled)")
Catch adue As AppDomainUnloadedException
Console.WriteLine("Main thread caught AppDomainUnloadedException: {0}", _
adue.Message)
End Try
' 4. Execute ThreadProc on the main thread without
' exception handling.
ThreadProc(" from the main application thread (unhandled)")
Console.WriteLine("Main: This message is never displayed.")
End Sub
Private Shared Sub ThreadProc(ByVal state As Object)
' Create an application domain, and create an instance
' of TestClass in the application domain. The first
' parameter of CreateInstanceAndUnwrap is the name of
' this executable. If you compile the example code using
' any name other than "Sample.exe", you must change the
' parameter appropriately.
Dim ad As AppDomain = AppDomain.CreateDomain("TestDomain")
Dim o As Object = ad.CreateInstanceAndUnwrap("Sample", "TestClass")
Dim tc As TestClass = CType(o, TestClass)
' In the new application domain, execute a method that
' unloads the AppDomain. The unhandled exception this
' causes ends the current thread.
tc.UnloadCurrentDomain(state)
Console.WriteLine("ThreadProc: This message is never displayed.")
End Sub
End Class
' TestClass derives from MarshalByRefObject, so it can be marshaled
' across application domain boundaries.
'
Public Class TestClass
Inherits MarshalByRefObject
Public Sub UnloadCurrentDomain(ByVal state As Object)
Console.WriteLine(vbLf & "Unloading the current AppDomain{0}.", state)
' Unload the current application domain. This causes
' an AppDomainUnloadedException to be thrown.
'
AppDomain.Unload(AppDomain.CurrentDomain)
End Sub
End Class
' This code example produces output similar to the following:
'
'Unloading the current AppDomain from a ThreadPool thread.
'
'Unloading the current AppDomain from an ordinary thread.
'
'Unloading the current AppDomain from the main application thread (handled).
'Main thread caught AppDomainUnloadedException: The application domain in which the thread was running has been unloaded.
'
'Unloading the current AppDomain from the main application thread (unhandled).
'
'Unhandled Exception: System.AppDomainUnloadedException: The application domain in which the thread was running has been unloaded.
' at TestClass.UnloadCurrentDomain(Object state)
' at Example.ThreadProc(Object state)
' at Example.Main()
'
Exemplo 2Example 2
O exemplo de código a seguir cria um domínio de aplicativo é descarregado e demonstra que um AppDomainUnloadedException será lançada em uma tentativa subsequente de acessar o domínio descarregado.The following code example creates and unloads an application domain, and demonstrates that an AppDomainUnloadedException is thrown on a subsequent attempt to access the unloaded domain.
using namespace System;
using namespace System::Reflection;
using namespace System::Security::Policy;
//for evidence Object*
int main()
{
//Create evidence for the new appdomain.
Evidence^ adevidence = AppDomain::CurrentDomain->Evidence;
// Create the new application domain.
AppDomain^ domain = AppDomain::CreateDomain( "MyDomain", adevidence );
Console::WriteLine( "Host domain: {0}", AppDomain::CurrentDomain->FriendlyName );
Console::WriteLine( "child domain: {0}", domain->FriendlyName );
// Unload the application domain.
AppDomain::Unload( domain );
try
{
Console::WriteLine();
// Note that the following statement creates an exception because the domain no longer exists.
Console::WriteLine( "child domain: {0}", domain->FriendlyName );
}
catch ( AppDomainUnloadedException^ /*e*/ )
{
Console::WriteLine( "The appdomain MyDomain does not exist." );
}
}
using System;
using System.Reflection;
using System.Security.Policy;
class ADUnload
{
public static void Main()
{
//Create evidence for the new appdomain.
Evidence adevidence = AppDomain.CurrentDomain.Evidence;
// Create the new application domain.
AppDomain domain = AppDomain.CreateDomain("MyDomain", adevidence);
Console.WriteLine("Host domain: " + AppDomain.CurrentDomain.FriendlyName);
Console.WriteLine("child domain: " + domain.FriendlyName);
// Unload the application domain.
AppDomain.Unload(domain);
try
{
Console.WriteLine();
// Note that the following statement creates an exception because the domain no longer exists.
Console.WriteLine("child domain: " + domain.FriendlyName);
}
catch (AppDomainUnloadedException e)
{
Console.WriteLine("The appdomain MyDomain does not exist.");
}
}
}
Imports System.Reflection
Imports System.Security.Policy
Class ADUnload
Public Shared Sub Main()
'Create evidence for the new appdomain.
Dim adevidence As Evidence = AppDomain.CurrentDomain.Evidence
' Create the new application domain.
Dim domain As AppDomain = AppDomain.CreateDomain("MyDomain", adevidence)
Console.WriteLine(("Host domain: " + AppDomain.CurrentDomain.FriendlyName))
Console.WriteLine(("child domain: " + domain.FriendlyName))
' Unload the application domain.
AppDomain.Unload(domain)
Try
Console.WriteLine()
' Note that the following statement creates an exception because the domain no longer exists.
Console.WriteLine(("child domain: " + domain.FriendlyName))
Catch e As AppDomainUnloadedException
Console.WriteLine("The appdomain MyDomain does not exist.")
End Try
End Sub
End Class
Comentários
No .NET Framework versão 2.0, um AppDomainUnloadedException que é o usuário não tratado no código tem o seguinte efeito:In the .NET Framework version 2.0, an AppDomainUnloadedException that is not handled in user code has the following effect:
Se um thread foi iniciado em código gerenciado, ela será encerrada.If a thread was started in managed code, it is terminated. A exceção sem tratamento não tem permissão para encerrar o aplicativo.The unhandled exception is not allowed to terminate the application.
Se uma tarefa está em execução em um ThreadPool thread, ela será encerrada e o thread é retornado ao pool de threads.If a task is executing on a ThreadPool thread, it is terminated and the thread is returned to the thread pool. A exceção sem tratamento não tem permissão para encerrar o aplicativo.The unhandled exception is not allowed to terminate the application.
Se um thread foi iniciado no código não gerenciado, como o thread principal do aplicativo, ele será encerrado.If a thread started in unmanaged code, such as the main application thread, it is terminated. A exceção sem tratamento tem permissão para prosseguir, e o sistema operacional encerre o aplicativo.The unhandled exception is allowed to proceed, and the operating system terminates the application.
AppDomainUnloadedException usa o HRESULT COR_E_APPDOMAINUNLOADED, que tem o valor 0x80131014.AppDomainUnloadedException uses the HRESULT COR_E_APPDOMAINUNLOADED, which has the value 0x80131014.
Para obter uma lista de valores de propriedade inicial para uma instância do AppDomainUnloadedException, consulte o AppDomainUnloadedException construtores.For a list of initial property values for an instance of AppDomainUnloadedException, see the AppDomainUnloadedException constructors.
Construtores
AppDomainUnloadedException() |
Inicializa uma nova instância da classe AppDomainUnloadedException.Initializes a new instance of the AppDomainUnloadedException class. |
AppDomainUnloadedException(SerializationInfo, StreamingContext) |
Inicializa uma nova instância da classe AppDomainUnloadedException com dados serializados.Initializes a new instance of the AppDomainUnloadedException class with serialized data. |
AppDomainUnloadedException(String) |
Inicializa uma nova instância da classe AppDomainUnloadedException com uma mensagem de erro especificada.Initializes a new instance of the AppDomainUnloadedException class with a specified error message. |
AppDomainUnloadedException(String, Exception) |
Inicializa uma nova instância da classe AppDomainUnloadedException com uma mensagem de erro especificada e uma referência à exceção interna que é a causa da exceção.Initializes a new instance of the AppDomainUnloadedException class with a specified error message and a reference to the inner exception that is the cause of this exception. |
Propriedades
Data |
Obtém uma coleção de pares de chave/valor que fornecem informações definidas pelo usuário adicionais sobre a exceção.Gets a collection of key/value pairs that provide additional user-defined information about the exception. (Herdado de Exception) |
HelpLink |
Obtém ou define um link para o arquivo de ajuda associado a essa exceção.Gets or sets a link to the help file associated with this exception. (Herdado de Exception) |
HResult |
Obtém ou define HRESULT, um valor numérico codificado que é atribuído a uma exceção específica.Gets or sets HRESULT, a coded numerical value that is assigned to a specific exception. (Herdado de Exception) |
InnerException |
Obtém a instância Exception que causou a exceção atual.Gets the Exception instance that caused the current exception. (Herdado de Exception) |
Message |
Obtém uma mensagem que descreve a exceção atual.Gets a message that describes the current exception. (Herdado de Exception) |
Source |
Obtém ou define o nome do aplicativo ou objeto que causa o erro.Gets or sets the name of the application or the object that causes the error. (Herdado de Exception) |
StackTrace |
Obtém uma representação de cadeia de caracteres de quadros imediatos na pilha de chamadas.Gets a string representation of the immediate frames on the call stack. (Herdado de Exception) |
TargetSite |
Obtém o método que gerou a exceção atual.Gets the method that throws the current exception. (Herdado de Exception) |
Métodos
Equals(Object) |
Determina se o objeto especificado é igual ao objeto atual.Determines whether the specified object is equal to the current object. (Herdado de Object) |
GetBaseException() |
Quando substituído em uma classe derivada, retorna a Exception que é a causa raiz de uma ou mais exceções subsequentes.When overridden in a derived class, returns the Exception that is the root cause of one or more subsequent exceptions. (Herdado de Exception) |
GetHashCode() |
Serve como a função de hash padrão.Serves as the default hash function. (Herdado de Object) |
GetObjectData(SerializationInfo, StreamingContext) |
Quando substituído em uma classe derivada, define o SerializationInfo com informações sobre a exceção.When overridden in a derived class, sets the SerializationInfo with information about the exception. (Herdado de Exception) |
GetType() |
Obtém o tipo de runtime da instância atual.Gets the runtime type of the current instance. (Herdado de Exception) |
MemberwiseClone() |
Cria uma cópia superficial do Object atual.Creates a shallow copy of the current Object. (Herdado de Object) |
ToString() |
Cria e retorna uma representação de cadeia de caracteres da exceção atual.Creates and returns a string representation of the current exception. (Herdado de Exception) |
Eventos
SerializeObjectState |
Ocorre quando uma exceção é serializada para criar um objeto de estado de exceção que contém dados serializados sobre a exceção.Occurs when an exception is serialized to create an exception state object that contains serialized data about the exception. (Herdado de Exception) |