Application.ApplicationExit 事件

public:
 static event EventHandler ^ ApplicationExit;

public static event EventHandler ApplicationExit;

public static event EventHandler? ApplicationExit;

member this.ApplicationExit : EventHandler 

Public Shared Custom Event ApplicationExit As EventHandler 

事件類型

範例

以下程式碼範例顯示兩個表單，當兩個表單都關閉時，應用程式會退出。 當應用程式開始並退出時，會記住每個表單的位置。 此範例示範如何利用 ApplicationExit 事件判斷何時表單位置應持久存在檔案，何時 FileStream 應關閉。

類別 MyApplicationContext 繼承 ApplicationContext 並記錄每個表單何時關閉，當兩者關閉時退出當前執行緒。 當形式關閉時，班級會記住該形式的位置。 當事件發生時 ApplicationExit ，類別會將每個位置寫入檔案中。 表單位置資料儲存在一個標題為 appdata.txt 檔案的檔案中，該檔案由 所決定 UserAppDataPath的位置建立。 方法 在 Main 給定 Application.Run(context)的情況下呼叫ApplicationContext啟動應用程式。

此程式碼摘自課程總覽中所示 ApplicationContext 範例。 完整程式碼列表請見 ApplicationContext 。

   MyApplicationContext()
   {
      _formCount = 0;
      
      // Handle the ApplicationExit event to know when the application is exiting.
      Application::ApplicationExit += gcnew EventHandler( this, &MyApplicationContext::OnApplicationExit );
      try
      {
         
         // Create a file that the application will store user specific data in.
         _userData = gcnew FileStream( String::Concat( Application::UserAppDataPath, "\\appdata.txt" ),FileMode::OpenOrCreate );
      }
      catch ( IOException^ e ) 
      {
         
         // Inform the user that an error occurred.
         MessageBox::Show( "An error occurred while attempting to show the application. The error is: {0}", dynamic_cast<String^>(e) );
         
         // Exit the current thread instead of showing the windows.
         ExitThread();
      }

      
      // Create both application forms and handle the Closed event
      // to know when both forms are closed.
      _form1 = gcnew AppForm1;
      _form1->Closed += gcnew EventHandler( this, &MyApplicationContext::OnFormClosed );
      _form1->Closing += gcnew CancelEventHandler( this, &MyApplicationContext::OnFormClosing );
      _formCount++;
      _form2 = gcnew AppForm2;
      _form2->Closed += gcnew EventHandler( this, &MyApplicationContext::OnFormClosed );
      _form2->Closing += gcnew CancelEventHandler( this, &MyApplicationContext::OnFormClosing );
      _formCount++;
      
      // Get the form positions based upon the user specific data.
      if ( ReadFormDataFromFile() )
      {
         
         // If the data was read from the file, set the form
         // positions manually.
         _form1->StartPosition = FormStartPosition::Manual;
         _form2->StartPosition = FormStartPosition::Manual;
         _form1->Bounds = _form1Position;
         _form2->Bounds = _form2Position;
      }

      
      // Show both forms.
      _form1->Show();
      _form2->Show();
   }

   void OnApplicationExit( Object^ /*sender*/, EventArgs^ /*e*/ )
   {
      
      // When the application is exiting, write the application data to the
      // user file and close it.
      WriteFormDataToFile();
      try
      {
         
         // Ignore any errors that might occur while closing the file handle.
         _userData->Close();
      }
      catch ( Exception^ ) 
      {
      }

   }

private:

private MyApplicationContext()
{
    _formCount = 0;

    // Handle the ApplicationExit event to know when the application is exiting.
    Application.ApplicationExit += new EventHandler(this.OnApplicationExit);

    try
    {
        // Create a file that the application will store user specific data in.
        _userData = new FileStream(Application.UserAppDataPath + "\\appdata.txt", FileMode.OpenOrCreate);
    }
    catch (IOException e)
    {
        // Inform the user that an error occurred.
        MessageBox.Show("An error occurred while attempting to show the application." +
                        "The error is:" + e.ToString());

        // Exit the current thread instead of showing the windows.
        ExitThread();
    }

    // Create both application forms and handle the Closed event
    // to know when both forms are closed.
    _form1 = new AppForm1();
    _form1.Closed += new EventHandler(OnFormClosed);
    _form1.Closing += new CancelEventHandler(OnFormClosing);
    _formCount++;

    _form2 = new AppForm2();
    _form2.Closed += new EventHandler(OnFormClosed);
    _form2.Closing += new CancelEventHandler(OnFormClosing);
    _formCount++;

    // Get the form positions based upon the user specific data.
    if (ReadFormDataFromFile())
    {
        // If the data was read from the file, set the form
        // positions manually.
        _form1.StartPosition = FormStartPosition.Manual;
        _form2.StartPosition = FormStartPosition.Manual;

        _form1.Bounds = _form1Position;
        _form2.Bounds = _form2Position;
    }

    // Show both forms.
    _form1.Show();
    _form2.Show();
}

private void OnApplicationExit(object sender, EventArgs e)
{
    // When the application is exiting, write the application data to the
    // user file and close it.
    WriteFormDataToFile();

    try
    {
        // Ignore any errors that might occur while closing the file handle.
        _userData.Close();
    }
    catch { }
}

Public Sub New()
    MyBase.New()
    _formCount = 0

    ' Handle the ApplicationExit event to know when the application is exiting.
    AddHandler Application.ApplicationExit, AddressOf OnApplicationExit

    Try
        ' Create a file that the application will store user specific data in.
        _userData = New FileStream(Application.UserAppDataPath + "\appdata.txt", FileMode.OpenOrCreate)

    Catch e As IOException
        ' Inform the user that an error occurred.
        MessageBox.Show("An error occurred while attempting to show the application." +
                        "The error is:" + e.ToString())

        ' Exit the current thread instead of showing the windows.
        ExitThread()
    End Try

    ' Create both application forms and handle the Closed event
    ' to know when both forms are closed.
    _form1 = New AppForm1()
    AddHandler _form1.Closed, AddressOf OnFormClosed
    AddHandler _form1.Closing, AddressOf OnFormClosing
    _formCount = _formCount + 1

    _form2 = New AppForm2()
    AddHandler _form2.Closed, AddressOf OnFormClosed
    AddHandler _form2.Closing, AddressOf OnFormClosing
    _formCount = _formCount + 1

    ' Get the form positions based upon the user specific data.
    If (ReadFormDataFromFile()) Then
        ' If the data was read from the file, set the form
        ' positions manually.
        _form1.StartPosition = FormStartPosition.Manual
        _form2.StartPosition = FormStartPosition.Manual

        _form1.Bounds = _form1Position
        _form2.Bounds = _form2Position
    End If

    ' Show both forms.
    _form1.Show()
    _form2.Show()
End Sub

Private Sub OnApplicationExit(ByVal sender As Object, ByVal e As EventArgs)
    ' When the application is exiting, write the application data to the
    ' user file and close it.
    WriteFormDataToFile()

    Try
        ' Ignore any errors that might occur while closing the file handle.
        _userData.Close()
    Catch
    End Try
End Sub

備註

您必須將事件處理程式附加到 ApplicationExit 事件上，才能執行未處理且必要的任務，應用程式才會停止執行。 你可以關閉這個應用程式開啟的檔案，或處理垃圾回收無法回收的物件。

由於這是靜態事件，你必須在事件處理程序中分離所有附加於此事件 ApplicationExit 的事件處理器。 如果你不把這些處理者分離，它們會持續附著在事件上，並持續消耗記憶體。

另請參閱

• Exit()