UnhandledExceptionMode UnhandledExceptionMode UnhandledExceptionMode UnhandledExceptionMode Enum

定义

定义 Windows 窗体应用程序应在何处发送未经处理的异常。Defines where a Windows Forms application should send unhandled exceptions.

public enum class UnhandledExceptionMode
public enum UnhandledExceptionMode
type UnhandledExceptionMode = 
Public Enum UnhandledExceptionMode
继承
UnhandledExceptionModeUnhandledExceptionModeUnhandledExceptionModeUnhandledExceptionMode

字段

Automatic Automatic Automatic Automatic 0

将所有异常都传送到 ThreadException 处理程序,除非应用程序的配置文件指定了其他位置。Route all exceptions to the ThreadException handler, unless the application's configuration file specifies otherwise.

CatchException CatchException CatchException CatchException 2

始终将异常传送到 ThreadException 处理程序。Always route exceptions to the ThreadException handler. 忽略应用程序配置文件。Ignore the application configuration file.

ThrowException ThrowException ThrowException ThrowException 1

从不将异常传送到 ThreadException 处理程序。Never route exceptions to the ThreadException handler. 忽略应用程序配置文件。Ignore the application configuration file.

示例

下面的代码示例设置 Windows 窗体线程和其他线程上发生的错误发生这两个错误的事件处理的程序。The following code example sets event handlers for both errors that occur on Windows Forms threads and errors that occur on other threads. 它会设置SetUnhandledExceptionMode,以便所有错误都处理由应用程序,而不考虑应用程序的用户配置文件中的设置。It sets SetUnhandledExceptionMode so that all errors are handled by the application, regardless of the settings in the application's user configuration file. 它使用ThreadException对于前者,事件和UnhandledException后者的事件。It uses the ThreadException event for the former, and the UnhandledException event for the latter. 由于UnhandledException不能阻止的应用程序终止,该示例只是会将错误记录在终止之前在系统事件日志中。Since UnhandledException cannot prevent an application from terminating, the example simply logs the error in the system Event Log prior to termination.

此示例假定您已经定义了两个Button控件,button1button2,然后在你Form类。This sample assumes that you have defined two Button controls, button1 and button2, on your Form class.

   // Creates a class to throw the error.
public:
   ref class ErrorHandler: public System::Windows::Forms::Form
   {
      // Inserts the code to create a form with a button.

      // Programs the button to throw an exception when clicked.
   private:
      void button1_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
      {
         throw gcnew ArgumentException( "The parameter was invalid" );
      }

   public:
      static void Main()
      {
         // Creates an instance of the methods that will handle the exception.
         CustomExceptionHandler ^ eh = gcnew CustomExceptionHandler;
         
         // Adds the event handler to the event.
         Application::ThreadException += gcnew ThreadExceptionEventHandler( eh, &Form1::CustomExceptionHandler::OnThreadException );
         
         // Runs the application.
         Application::Run( gcnew ErrorHandler );
      }
   };

   // Creates a class to handle the exception event.
internal:
   ref class CustomExceptionHandler
   {
      // Handles the exception event.
   public:
      void OnThreadException( Object^ /*sender*/, ThreadExceptionEventArgs^ t )
      {
         System::Windows::Forms::DialogResult result = ::DialogResult::Cancel;
         try
         {
            result = this->ShowThreadExceptionDialog( t->Exception );
         }
         catch ( Exception^ ) 
         {
            try
            {
               MessageBox::Show( "Fatal Error", "Fatal Error", MessageBoxButtons::AbortRetryIgnore, MessageBoxIcon::Stop );
            }
            finally
            {
               Application::Exit();
            }
         }
         
         // Exits the program when the user clicks Abort.
         if ( result == ::DialogResult::Abort )
         {
            Application::Exit();
         }
      }

      // Creates the error message and displays it.
   private:
      System::Windows::Forms::DialogResult ShowThreadExceptionDialog( Exception^ e )
      {
         String^ errorMsg = "An error occurred please contact the adminstrator with the following information:\n\n";
         errorMsg = String::Concat( errorMsg, e->Message, "\n\nStack Trace:\n", e->StackTrace );
         return MessageBox::Show( errorMsg, "Application Error", MessageBoxButtons::AbortRetryIgnore, MessageBoxIcon::Stop );
      }
   };
Thread newThread = null;

// Starts the application. 
[SecurityPermission(SecurityAction.Demand, Flags = SecurityPermissionFlag.ControlAppDomain)]
public static void Main(string[] args)
{
    // Add the event handler for handling UI thread exceptions to the event.
    Application.ThreadException += new ThreadExceptionEventHandler(ErrorHandlerForm.Form1_UIThreadException);

    // Set the unhandled exception mode to force all Windows Forms errors to go through
    // our handler.
    Application.SetUnhandledExceptionMode(UnhandledExceptionMode.CatchException);

    // Add the event handler for handling non-UI thread exceptions to the event. 
    AppDomain.CurrentDomain.UnhandledException +=
        new UnhandledExceptionEventHandler(CurrentDomain_UnhandledException);

    // Runs the application.
    Application.Run(new ErrorHandlerForm());
}

// Programs the button to throw an exception when clicked.
private void button1_Click(object sender, System.EventArgs e)
{
    throw new ArgumentException("The parameter was invalid");
}

// Start a new thread, separate from Windows Forms, that will throw an exception.
private void button2_Click(object sender, System.EventArgs e)
{
    ThreadStart newThreadStart = new ThreadStart(newThread_Execute);
    newThread = new Thread(newThreadStart);
    newThread.Start();
}

// The thread we start up to demonstrate non-UI exception handling. 
void newThread_Execute()
{
    throw new Exception("The method or operation is not implemented.");
}

// Handle the UI exceptions by showing a dialog box, and asking the user whether
// or not they wish to abort execution.
private static void Form1_UIThreadException(object sender, ThreadExceptionEventArgs t)
{
    DialogResult result = DialogResult.Cancel;
    try
    {
        result = ShowThreadExceptionDialog("Windows Forms Error", t.Exception);
    }
    catch
    {
        try
        {
            MessageBox.Show("Fatal Windows Forms Error",
                "Fatal Windows Forms Error", MessageBoxButtons.AbortRetryIgnore, MessageBoxIcon.Stop);
        }
        finally
        {
            Application.Exit();
        }
    }

    // Exits the program when the user clicks Abort.
    if (result == DialogResult.Abort)
        Application.Exit();
}

// Handle the UI exceptions by showing a dialog box, and asking the user whether
// or not they wish to abort execution.
// NOTE: This exception cannot be kept from terminating the application - it can only 
// log the event, and inform the user about it. 
private static void CurrentDomain_UnhandledException(object sender, UnhandledExceptionEventArgs e)
{
    try
    {
        Exception ex = (Exception)e.ExceptionObject;
        string errorMsg = "An application error occurred. Please contact the adminstrator " +
            "with the following information:\n\n";

        // Since we can't prevent the app from terminating, log this to the event log.
        if (!EventLog.SourceExists("ThreadException"))
        {
            EventLog.CreateEventSource("ThreadException", "Application");
        }

        // Create an EventLog instance and assign its source.
        EventLog myLog = new EventLog();
        myLog.Source = "ThreadException";
        myLog.WriteEntry(errorMsg + ex.Message + "\n\nStack Trace:\n" + ex.StackTrace);
    }
    catch (Exception exc)
    {
        try
        {
            MessageBox.Show("Fatal Non-UI Error",
                "Fatal Non-UI Error. Could not write the error to the event log. Reason: "
                + exc.Message, MessageBoxButtons.OK, MessageBoxIcon.Stop);
        }
        finally
        {
            Application.Exit();
        }
    }
}

// Creates the error message and displays it.
private static DialogResult ShowThreadExceptionDialog(string title, Exception e)
{
    string errorMsg = "An application error occurred. Please contact the adminstrator " +
        "with the following information:\n\n";
    errorMsg = errorMsg + e.Message + "\n\nStack Trace:\n" + e.StackTrace;
    return MessageBox.Show(errorMsg, title, MessageBoxButtons.AbortRetryIgnore,
        MessageBoxIcon.Stop);
}
     Private newThread As Thread = Nothing

     ' Starts the application. 
     <SecurityPermission(SecurityAction.Demand, Flags:=SecurityPermissionFlag.ControlAppDomain)> _
     Public Shared Sub Main()
         ' Add the event handler for handling UI thread exceptions to the event.
         AddHandler Application.ThreadException, AddressOf ErrorHandlerForm.Form1_UIThreadException

         ' Set the unhandled exception mode to force all Windows Forms errors to go through
         ' our handler.
         Application.SetUnhandledExceptionMode(UnhandledExceptionMode.CatchException)

         ' Add the event handler for handling non-UI thread exceptions to the event. 
         AddHandler AppDomain.CurrentDomain.UnhandledException, AddressOf CurrentDomain_UnhandledException

         ' Runs the application.
         Application.Run(New ErrorHandlerForm())
     End Sub


     ' Programs the button to throw an exception when clicked.
     Private Sub button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles button1.Click
         Throw New ArgumentException("The parameter was invalid")
     End Sub

     ' Start a new thread, separate from Windows Forms, that will throw an exception.
     Private Sub button2_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles button2.Click
         Dim newThreadStart As New ThreadStart(AddressOf newThread_Execute)
         newThread = New Thread(newThreadStart)
         newThread.Start()
     End Sub


     ' The thread we start up to demonstrate non-UI exception handling. 
     Sub newThread_Execute()
         Throw New Exception("The method or operation is not implemented.")
     End Sub


     ' Handle the UI exceptions by showing a dialog box, and asking the user whether
     ' or not they wish to abort execution.
     Private Shared Sub Form1_UIThreadException(ByVal sender As Object, ByVal t As ThreadExceptionEventArgs)
         Dim result As System.Windows.Forms.DialogResult = _
             System.Windows.Forms.DialogResult.Cancel
         Try
             result = ShowThreadExceptionDialog("Windows Forms Error", t.Exception)
         Catch
             Try
                 MessageBox.Show("Fatal Windows Forms Error", _
                     "Fatal Windows Forms Error", MessageBoxButtons.AbortRetryIgnore, MessageBoxIcon.Stop)
             Finally
                 Application.Exit()
             End Try
         End Try

         ' Exits the program when the user clicks Abort.
         If result = DialogResult.Abort Then
             Application.Exit()
         End If
     End Sub

     ' Handle the UI exceptions by showing a dialog box, and asking the user whether
     ' or not they wish to abort execution.
     ' NOTE: This exception cannot be kept from terminating the application - it can only 
     ' log the event, and inform the user about it. 
     Private Shared Sub CurrentDomain_UnhandledException(ByVal sender As Object, _
     ByVal e As UnhandledExceptionEventArgs)
         Try
             Dim ex As Exception = CType(e.ExceptionObject, Exception)
             Dim errorMsg As String = "An application error occurred. Please contact the adminstrator " & _
                 "with the following information:" & ControlChars.Lf & ControlChars.Lf

             ' Since we can't prevent the app from terminating, log this to the event log.
             If (Not EventLog.SourceExists("ThreadException")) Then
                 EventLog.CreateEventSource("ThreadException", "Application")
             End If

             ' Create an EventLog instance and assign its source.
             Dim myLog As New EventLog()
             myLog.Source = "ThreadException"
             myLog.WriteEntry((errorMsg + ex.Message & ControlChars.Lf & ControlChars.Lf & _
                 "Stack Trace:" & ControlChars.Lf & ex.StackTrace))
         Catch exc As Exception
             Try
                 MessageBox.Show("Fatal Non-UI Error", "Fatal Non-UI Error. Could not write the error to the event log. " & _
                     "Reason: " & exc.Message, MessageBoxButtons.OK, MessageBoxIcon.Stop)
             Finally
                 Application.Exit()
             End Try
         End Try
     End Sub


     ' Creates the error message and displays it.
     Private Shared Function ShowThreadExceptionDialog(ByVal title As String, ByVal e As Exception) As DialogResult
         Dim errorMsg As String = "An application error occurred. Please contact the adminstrator " & _
"with the following information:" & ControlChars.Lf & ControlChars.Lf
         errorMsg = errorMsg & e.Message & ControlChars.Lf & _
ControlChars.Lf & "Stack Trace:" & ControlChars.Lf & e.StackTrace

         Return MessageBox.Show(errorMsg, title, MessageBoxButtons.AbortRetryIgnore, MessageBoxIcon.Stop)
     End Function

注解

此枚举由SetUnhandledExceptionModeThis enumeration is used by SetUnhandledExceptionMode.

备注

在.NET Framework 2.0 版中,公共语言运行时行为更改为允许未经处理的异常传播到调用堆栈。In the .NET Framework version 2.0, the common language runtime behavior changed to allow unhandled exceptions to propagate up the call stack. 可以通过应用程序配置文件禁用此行为。This behavior can be disabled via the application configuration file. 有关详细信息,请参阅托管线程异常For more information, see Exceptions in Managed Threads.

适用于