Console.CancelKeyPress イベント

.NET Framework クラス ライブラリ リファレンス

Console.CancelKeyPress イベント

メモ : このイベントは、.NET Framework version 2.0 で新しく追加されたものです。

Control の修飾子キー (Ctrl) および C コンソール キー (C) が同時に押された場合、つまり、Ctrl キーと C キーが同時に押された場合に発生します。

名前空間: System
アセンブリ: mscorlib (mscorlib.dll 内)
構文

Visual Basic (宣言)

Public Shared Event CancelKeyPress
 As ConsoleCancelEventHandler

Visual Basic (使用法)

Dim handler As ConsoleCancelEventHandler

AddHandler Console.CancelKeyPress, handler

C#

public static event ConsoleCancelEventHandler
 CancelKeyPress

C++

public:
static event ConsoleCancelEventHandler^ CancelKeyPress {
    void add (ConsoleCancelEventHandler^ value);
    void remove (ConsoleCancelEventHandler^ value);
}

J#

/** @event */
public static void add_CancelKeyPress
 (ConsoleCancelEventHandler value)

/** @event */
public static void remove_CancelKeyPress
 (ConsoleCancelEventHandler value)

JScript

JScript では、イベントは使用できますが、新規に宣言することはできません。

解説

このイベントは、System.ConsoleCancelEventHandler および System.ConsoleCancelEventArgs と組み合わせて使用します。アプリケーションは、コンソール アプリケーションが CancelKeyPress イベントを通じて受け取った Ctrl + C のシグナルによって、処理を続行するか、強制終了するかを判断できます。イベント処理の詳細については、「イベントの利用」を参照してください。

このイベントを使用することで、Ctrl + C シグナルに対するアプリケーションの動作を明示的に制御できます。アプリケーションの要件がそれほど複雑でなければ、このイベントの代わりに TreatControlCAsInput プロパティを使用することもできます。

使用例

CancelKeyPress イベントを使ったコード例を次に示します。

Visual Basic

' This example demonstrates:
' the Console.CancelKeyPress event,
' the ConsoleCancelEventHandler delegate, 
' the ConsoleCancelEventArgs.SpecialKey property, and 
' the ConsoleCancelEventArgs.Cancel property.

Imports System

Class Sample
    Public Shared Sub Main()
 
        Dim cki As ConsoleKeyInfo
        
        ' Clear the screen.
        Console.Clear()
        
        ' Turn off the default system behavior when CTRL+C is pressed.
 When 
        ' Console.TreatControlCAsInput is false, CTRL+C is treated as
 an
        ' interrupt instead of as input.
        Console.TreatControlCAsInput = False
        
        ' Establish an event handler to process key press events.
        AddHandler Console.CancelKeyPress, AddressOf
 myHandler

        While True
            ' Prompt the user.
            Console.Write("Press any key, or 'X'
 to quit, or ")
            Console.WriteLine("CTRL+C to interrupt the read operation:")
            
            ' Start a console read operation. Do not display the input.
            cki = Console.ReadKey(True)
            
            ' Announce the name of the key that was pressed .
            Console.WriteLine("  Key pressed: {0}"
 & vbCrLf, cki.Key)
            
            ' Exit if the user pressed the 'X' key.
            If cki.Key = ConsoleKey.X Then
 Exit While
        End While
    End Sub 'Main
     
'   When you press CTRL+C, the read operation is interrupted and the
 
'   console cancel event handler, myHandler, is invoked. Upon entry
 
'   to the event handler, the Cancel property is false, which means
 
'   the current process will terminate when the event handler terminates.
 
'   However, the event handler sets the Cancel property to true, which
 
'   means the process will not terminate and the read operation will
 resume.

    Protected Shared Sub
 myHandler(ByVal sender As Object,
 _
                                   ByVal args As
 ConsoleCancelEventArgs) 
        ' Announce that the event handler has been invoked.
        Console.WriteLine(vbCrLf & "The read operation has
 been interrupted.")
        
        ' Announce which key combination was pressed.
        Console.WriteLine("  Key pressed: {0}", args.SpecialKey)
        
        ' Announce the initial value of the Cancel property.
        Console.WriteLine("  Cancel property: {0}",
 args.Cancel)
        
        ' Set the Cancel property to true to prevent the process from
 terminating.
        Console.WriteLine("Setting the Cancel property to true...")
        args.Cancel = True
        
        ' Announce the new value of the Cancel property.
        Console.WriteLine("  Cancel property: {0}",
 args.Cancel)
        Console.WriteLine("The read operation will resume..."
 & vbCrLf)
    
    End Sub 'myHandler
End Class 'Sample
'
'This code example produces results similar to the following text:
'
'Press any key, or 'X' to quit, or CTRL+C to interrupt the read operation:
'  Key pressed: J
'
'Press any key, or 'X' to quit, or CTRL+C to interrupt the read operation:
'  Key pressed: Enter
'
'Press any key, or 'X' to quit, or CTRL+C to interrupt the read operation:
'
'The read operation has been interrupted.
'  Key pressed: ControlC
'  Cancel property: False
'Setting the Cancel property to true...
'  Cancel property: True
'The read operation will resume...
'
'  Key pressed: Q
'
'Press any key, or 'X' to quit, or CTRL+C to interrupt the read operation:
'  Key pressed: X
'

C#

// This example demonstrates:
// the Console.CancelKeyPress event,
// the ConsoleCancelEventHandler delegate, 
// the ConsoleCancelEventArgs.SpecialKey property, and 
// the ConsoleCancelEventArgs.Cancel property.

using System;

class Sample 
{
    public static void Main()
    {
    ConsoleKeyInfo cki;

// Clear the screen.
    Console.Clear();

// Turn off the default system behavior when CTRL+C is pressed. When
 
// Console.TreatControlCAsInput is false, CTRL+C is treated as an
// interrupt instead of as input.
    Console.TreatControlCAsInput = false;

// Establish an event handler to process key press events.
    Console.CancelKeyPress += new ConsoleCancelEventHandler(myHandler);
    while (true)
        {
// Prompt the user.
        Console.Write("Press any key, or 'X' to quit, or ");
        Console.WriteLine("CTRL+C to interrupt the read operation:");

// Start a console read operation. Do not display the input.
        cki = Console.ReadKey(true);

// Announce the name of the key that was pressed .
        Console.WriteLine("  Key pressed: {0}\n", cki.Key);

// Exit if the user pressed the 'X' key.
        if (cki.Key == ConsoleKey.X) break;
        }
    }

/*
   When you press CTRL+C, the read operation is interrupted and the 
   console cancel event handler, myHandler, is invoked. Upon entry 
   to the event handler, the Cancel property is false, which means
 
   the current process will terminate when the event handler terminates. 
   However, the event handler sets the Cancel property to true,
 which 
   means the process will not terminate and the read operation will resume.
*/
    protected static void
 myHandler(object sender, ConsoleCancelEventArgs args)
    {
// Announce that the event handler has been invoked.
    Console.WriteLine("\nThe read operation has been interrupted.");

// Announce which key combination was pressed.
    Console.WriteLine("  Key pressed: {0}", args.SpecialKey);

// Announce the initial value of the Cancel property.
    Console.WriteLine("  Cancel property: {0}", args.Cancel);

// Set the Cancel property to true to prevent the process from terminating.
    Console.WriteLine("Setting the Cancel property to true...");
    args.Cancel = true;

// Announce the new value of the Cancel property.
    Console.WriteLine("  Cancel property: {0}", args.Cancel);
    Console.WriteLine("The read operation will resume...\n");
    }
}
/*
This code example produces results similar to the following text:

Press any key, or 'X' to quit, or CTRL+C to interrupt the read operation:
  Key pressed: J

Press any key, or 'X' to quit, or CTRL+C to interrupt the read operation:
  Key pressed: Enter

Press any key, or 'X' to quit, or CTRL+C to interrupt the read operation:

The read operation has been interrupted.
  Key pressed: ControlC
  Cancel property: False
Setting the Cancel property to true...
  Cancel property: True
The read operation will resume...

  Key pressed: Q

Press any key, or 'X' to quit, or CTRL+C to interrupt the read operation:
  Key pressed: X

*/

C++

// This example demonstrates:
// the Console.CancelKeyPress event,
// the ConsoleCancelEventHandler delegate, 
// the ConsoleCancelEventArgs.SpecialKey property, and 
// the ConsoleCancelEventArgs.Cancel property.

using namespace System;

// When you press CTRL+C, the read operation is interrupted and the
 
// console cancel event handler, myHandler, is invoked. Upon entry 
// to the event handler, the Cancel property is false, which means 
// the current process will terminate when the event handler terminates.
 
// However, the event handler sets the Cancel property to true, which
 
// means the process will not terminate and the read operation will
 resume.
void OnCancelKeyPressed(Object^ sender, 
    ConsoleCancelEventArgs^ args)
{
    // Announce that the event handler has been invoked.
    Console::WriteLine("{0}The read operation has been interrupted.",
        Environment::NewLine);

    // Announce which key combination was pressed.
    Console::WriteLine("  Key pressed: {0}", args->SpecialKey);

    // Announce the initial value of the Cancel property.
    Console::WriteLine("  Cancel property: {0}", args->Cancel);

    // Set the Cancel property to true to prevent the process from 
    // terminating.
    Console::WriteLine("Setting the Cancel property to true...");
    args->Cancel = true;

    // Announce the new value of the Cancel property.
    Console::WriteLine("  Cancel property: {0}", args->Cancel);
    Console::WriteLine("The read operation will resume...{0}",
        Environment::NewLine);
}

int main()
{       
    // Clear the screen.
    Console::Clear();

    // Turn off the default system behavior when CTRL+C is pressed. When
 
    // Console.TreatControlCAsInput is false, CTRL+C is treated as an
    // interrupt instead of as input.
    Console::TreatControlCAsInput = false;

    // Establish an event handler to process key press events.
    Console::CancelKeyPress += 
        gcnew ConsoleCancelEventHandler(OnCancelKeyPressed);

    while (true)
    {
        // Prompt the user.
        Console::Write("Press any key, or 'X' to quit, or ");
        Console::WriteLine("CTRL+C to interrupt the read operation:");

        // Start a console read operation. Do not display the input.
        ConsoleKeyInfo^ keyInfo = Console::ReadKey(true);

        // Announce the name of the key that was pressed .
        Console::WriteLine("  Key pressed: {0}{1}", keyInfo->Key, 
            Environment::NewLine);

        // Exit if the user pressed the 'X' key.
        if (keyInfo->Key == ConsoleKey::X)
        {
            break;
        }
    }
}
/*
This code example produces results similar to the following text:

Press any key, or 'X' to quit, or CTRL+C to interrupt the read operation:
Key pressed: J

Press any key, or 'X' to quit, or CTRL+C to interrupt the read operation:
Key pressed: Enter

Press any key, or 'X' to quit, or CTRL+C to interrupt the read operation:

The read operation has been interrupted.
Key pressed: ControlC
Cancel property: False
Setting the Cancel property to true...
Cancel property: True
The read operation will resume...

Key pressed: Q

Press any key, or 'X' to quit, or CTRL+C to interrupt the read operation:
Key pressed: X

*/

.NET Framework のセキュリティ

• UIPermission  (セーフ トップレベル ウィンドウおよびサブウィンドウを変更するために必要なアクセス許可)。UIPermissionWindow.SafeTopLevelWindows (関連する列挙体)

プラットフォーム

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

開発プラットフォームの中には、.NET Framework によってサポートされていないバージョンがあります。サポートされているバージョンについては、「システム要件」を参照してください。

バージョン情報

.NET Framework
サポート対象 : 2.0

参照

関連項目
Console クラス
Console メンバ
System 名前空間
ConsoleCancelEventArgs
ConsoleCancelEventHandler
Console.TreatControlCAsInput プロパティ