Application.Exit 事件

定义

在应用程序关闭且无法取消之前发生。

public:
 event System::Windows::ExitEventHandler ^ Exit;
public event System.Windows.ExitEventHandler Exit;
member this.Exit : System.Windows.ExitEventHandler 
Public Custom Event Exit As ExitEventHandler 

事件类型

示例

以下示例演示如何:

  • 处理 Exit 事件。

  • 检查并更新 ApplicationExitCodeExitEventArgs属性。

  • 将条目写入独立存储中的应用程序日志。

  • 将应用程序状态保存到独立存储。

<Application x:Class="CSharp.App"
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  StartupUri="MainWindow.xaml" 
  ShutdownMode="OnExplicitShutdown"
  Exit="App_Exit"
    >
</Application>
using System;
using System.Collections;
using System.Windows;
using System.IO;
using System.IO.IsolatedStorage;

namespace CSharp
{
    public enum ApplicationExitCode
    {
        Success = 0,
        Failure = 1,
        CantWriteToApplicationLog = 2,
        CantPersistApplicationState = 3
    }

    public partial class App : Application
    {
        void App_Exit(object sender, ExitEventArgs e)
        {
            try
            {
                // Write entry to application log
                if (e.ApplicationExitCode == (int)ApplicationExitCode.Success)
                {
                    WriteApplicationLogEntry("Failure", e.ApplicationExitCode);
                }
                else
                {
                    WriteApplicationLogEntry("Success", e.ApplicationExitCode);
                }
            }
            catch
            {
                // Update exit code to reflect failure to write to application log
                e.ApplicationExitCode = (int)ApplicationExitCode.CantWriteToApplicationLog;
            }

            // Persist application state
            try
            {
                PersistApplicationState();
            }
            catch
            {
                // Update exit code to reflect failure to persist application state
                e.ApplicationExitCode = (int)ApplicationExitCode.CantPersistApplicationState;
            }
        }

        void WriteApplicationLogEntry(string message, int exitCode)
        {
            // Write log entry to file in isolated storage for the user
            IsolatedStorageFile store = IsolatedStorageFile.GetUserStoreForAssembly();
            using (Stream stream = new IsolatedStorageFileStream("log.txt", FileMode.Append, FileAccess.Write, store))
            using (StreamWriter writer = new StreamWriter(stream))
            {
                string entry = string.Format("{0}: {1} - {2}", message, exitCode, DateTime.Now);
                writer.WriteLine(entry);
            }
        }

        void PersistApplicationState()
        {
            // Persist application state to file in isolated storage for the user
            IsolatedStorageFile store = IsolatedStorageFile.GetUserStoreForAssembly();
            using (Stream stream = new IsolatedStorageFileStream("state.txt", FileMode.Create, store))
            using (StreamWriter writer = new StreamWriter(stream))
            {
                foreach (DictionaryEntry entry in this.Properties)
                {
                    writer.WriteLine(entry.Value);
                }
            }
        }
    }
}

Imports System.Collections
Imports System.Windows
Imports System.IO
Imports System.IO.IsolatedStorage

Namespace VisualBasic
    Public Enum ApplicationExitCode
        Success = 0
        Failure = 1
        CantWriteToApplicationLog = 2
        CantPersistApplicationState = 3
    End Enum

    Partial Public Class App
        Inherits Application
        Private Sub App_Exit(ByVal sender As Object, ByVal e As ExitEventArgs)
            Try
                ' Write entry to application log
                If e.ApplicationExitCode = CInt(ApplicationExitCode.Success) Then
                    WriteApplicationLogEntry("Failure", e.ApplicationExitCode)
                Else
                    WriteApplicationLogEntry("Success", e.ApplicationExitCode)
                End If
            Catch
                ' Update exit code to reflect failure to write to application log
                e.ApplicationExitCode = CInt(ApplicationExitCode.CantWriteToApplicationLog)
            End Try

            ' Persist application state
            Try
                PersistApplicationState()
            Catch
                ' Update exit code to reflect failure to persist application state
                e.ApplicationExitCode = CInt(ApplicationExitCode.CantPersistApplicationState)
            End Try
        End Sub

        Private Sub WriteApplicationLogEntry(ByVal message As String, ByVal exitCode As Integer)
            ' Write log entry to file in isolated storage for the user
            Dim store As IsolatedStorageFile = IsolatedStorageFile.GetUserStoreForAssembly()
            Using stream As Stream = New IsolatedStorageFileStream("log.txt", FileMode.Append, FileAccess.Write, store)
                Using writer As New StreamWriter(stream)
                    Dim entry As String = String.Format("{0}: {1} - {2}", message, exitCode, Date.Now)
                    writer.WriteLine(entry)
                End Using
            End Using
        End Sub

        Private Sub PersistApplicationState()
            ' Persist application state to file in isolated storage for the user
            Dim store As IsolatedStorageFile = IsolatedStorageFile.GetUserStoreForAssembly()
            Using stream As Stream = New IsolatedStorageFileStream("state.txt", FileMode.Create, store)
                Using writer As New StreamWriter(stream)
                    For Each entry As DictionaryEntry In Me.Properties
                        writer.WriteLine(entry.Value)
                    Next entry
                End Using
            End Using
        End Sub
    End Class
End Namespace

注解

应用程序可能由于以下任一原因而关闭:

可以通过处理 Exit 事件来检测应用程序关闭的时间,并根据需要执行任何其他处理。

无需显式调用Shutdown时,还可以处理Exit以检查或更改应用程序退出代码。 退出代码从 ApplicationExitCode 传递给事件处理程序的参数的 ExitEventArgs 属性公开 Exit 。 当应用程序停止运行时,退出代码将传递给操作系统以供后续处理。

如果应用程序处理事件 SessionEnding 并随后取消它,则不会引发 , Exit 并且应用程序继续按照关闭模式运行。

可以从 XAML 浏览器应用程序 (XBAP) 设置退出代码,但该值将被忽略。

对于 XBAP, Exit 在以下情况下引发:

  • 导航离开 XBAP。
  • 当托管 XBAP 的浏览器选项卡关闭时。
  • 关闭浏览器时。

在所有情况下,都会忽略 属性的值 ApplicationExitCode

有关 XBAP 支持的详细信息,请参阅 有关 WPF 浏览器托管应用程序的常见问题 (XBAP)

适用于

另请参阅