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ConsoleCancelEventArgs Класс

Определение

Предоставляет данные для события CancelKeyPress. Этот класс не наследуется.

public ref class ConsoleCancelEventArgs sealed : EventArgs
public sealed class ConsoleCancelEventArgs : EventArgs
[System.Serializable]
public sealed class ConsoleCancelEventArgs : EventArgs
type ConsoleCancelEventArgs = class
    inherit EventArgs
[<System.Serializable>]
type ConsoleCancelEventArgs = class
    inherit EventArgs
Public NotInheritable Class ConsoleCancelEventArgs
Inherits EventArgs
Наследование
ConsoleCancelEventArgs
Атрибуты

Примеры

В следующем примере показано, как использовать ConsoleCancelEventArgs класс для обработки события.

using namespace System;

void OnCancelKeyPressed(Object^ sender, 
    ConsoleCancelEventArgs^ args)
{
    Console::WriteLine("{0}The read operation has been interrupted.",
        Environment::NewLine);

    Console::WriteLine("  Key pressed: {0}", args->SpecialKey);

    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();

    // 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;
        }
    }
}
// The example displays output similar to the following:
//    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
using System;

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

        Console.Clear();

        // Establish an event handler to process key press events.
        Console.CancelKeyPress += new ConsoleCancelEventHandler(myHandler);
        while (true)
        {
            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: {cki.Key}\n");

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

    protected static void myHandler(object sender, ConsoleCancelEventArgs args)
    {
        Console.WriteLine("\nThe read operation has been interrupted.");

        Console.WriteLine($"  Key pressed: {args.SpecialKey}");

        Console.WriteLine($"  Cancel property: {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: {args.Cancel}");
        Console.WriteLine("The read operation will resume...\n");
    }
}
// The example displays output similar to the following:
//    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
open System

let myHandler sender (args: ConsoleCancelEventArgs) =
    printfn "\nThe read operation has been interrupted."

    printfn $"  Key pressed: {args.SpecialKey}"

    printfn $"  Cancel property: {args.Cancel}"

    // Set the Cancel property to true to prevent the process from terminating.
    printfn "Setting the Cancel property to true..."
    args.Cancel <- true

    // Announce the new value of the Cancel property.
    printfn $"  Cancel property: {args.Cancel}"
    printfn "The read operation will resume...\n"

// Establish an event handler to process key press events.
Console.CancelKeyPress.AddHandler(ConsoleCancelEventHandler myHandler)

let mutable quit = false
while not quit do
    printf "Press any key, or 'X' to quit, or "
    printfn "CTRL+C to interrupt the read operation:"

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

    // Announce the name of the key that was pressed .
    printfn $"  Key pressed: {cki.Key}\n"

    // Exit if the user pressed the 'X' key.
    if cki.Key = ConsoleKey.X then
        quit <- true

// The example displays output similar to the following:
//    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
Class Sample
    Public Shared Sub Main() 
        Dim cki As ConsoleKeyInfo
        
        Console.Clear()
        
        ' Establish an event handler to process key press events.
        AddHandler Console.CancelKeyPress, AddressOf myHandler

        While True
            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: {cki.Key}{vbCrLf}")
            
            ' Exit if the user pressed the 'X' key.
            If cki.Key = ConsoleKey.X Then Exit While
        End While
    End Sub

    Protected Shared Sub myHandler(ByVal sender As Object, _
                                   ByVal args As ConsoleCancelEventArgs) 
        Console.WriteLine($"{vbCrLf}The read operation has been interrupted.")
        
        Console.WriteLine($"  Key pressed: {args.SpecialKey}")
        
        Console.WriteLine($"  Cancel property: {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($"  Cancel property: {args.Cancel}")
        Console.WriteLine($"The read operation will resume...{vbCrLf}")
    End Sub
End Class
' The example diplays output similar to the following:
'    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

Комментарии

Пользователь может прервать процесс консольного приложения, одновременно нажав Control клавишу-модификатор и C консольную клавишу (CTRL+C) или Control клавишу-модификатор и консольную клавишу Break (CTRL+Break). Следовательно, .NET предоставляет ConsoleCancelEventArgs обработчику событий объект , Console.CancelKeyPress чтобы указать, следует ли отменить процесс.

Если свойству Cancel задано значение true в обработчике событий, процесс возобновляется; в противном случае процесс завершается. По умолчанию свойство имеет falseзначение ConsoleCancelEventArgs , и процесс завершается.

Свойства

Cancel

Получает или задает значение, указывающее, останавливается ли текущий процесс при одновременном нажатии клавиши-модификатора Control и клавиши консоли C (CTRL+C) либо клавиш CTRL+BREAK. Значение по умолчанию false, которое используется для завершения текущего процесса.

SpecialKey

Возвращает сочетание клавиш, с помощью которого была прервана работа текущего процесса.

Методы

Equals(Object)

Определяет, равен ли указанный объект текущему объекту.

(Унаследовано от Object)
GetHashCode()

Служит хэш-функцией по умолчанию.

(Унаследовано от Object)
GetType()

Возвращает объект Type для текущего экземпляра.

(Унаследовано от Object)
MemberwiseClone()

Создает неполную копию текущего объекта Object.

(Унаследовано от Object)
ToString()

Возвращает строку, представляющую текущий объект.

(Унаследовано от Object)

Применяется к