UnhandledExceptionMode 枚举

定义

定义 Windows 窗体应用程序应在何处发送未经处理的异常。

C#
public enum UnhandledExceptionMode
继承
UnhandledExceptionMode

字段

名称 说明
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。

CatchException 2

始终将异常传送到 ThreadException 处理程序。 忽略应用程序配置文件。

ThrowException 1

从不将异常传送到 ThreadException 处理程序。 忽略应用程序配置文件。

示例

下面的代码示例为Windows 窗体线程上发生的错误和其他线程上发生的错误设置事件处理程序。 它进行设置 SetUnhandledExceptionMode ,以便应用程序处理所有错误,而不考虑应用程序的用户配置文件中的设置。 它为前者使用 ThreadException 事件, UnhandledException 为后者使用 事件。 由于 UnhandledException 无法阻止应用程序终止,本示例只需在终止前将错误记录在系统事件日志中。

此示例假定你已在类上Form定义了两个Button控件 button1button2

C#
Thread newThread = null;

// Starts the application.
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);
}

注解

此枚举由 SetUnhandledExceptionMode使用。

备注

在 .NET Framework 2.0 版中,公共语言运行时行为已更改,允许未经处理的异常向上传播调用堆栈。 可以通过应用程序配置文件禁用此行为。 有关详细信息,请参阅托管线程异常

适用于

产品 版本
.NET Framework 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
Windows Desktop 3.0, 3.1, 5, 6, 7, 8, 9