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ConsoleCancelEventHandler Delegate

Represents the method that will handle the CancelKeyPress event of a System::Console.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)
public delegate void ConsoleCancelEventHandler(
	Object^ sender, 
	ConsoleCancelEventArgs^ e
)

Parameters

sender
Type: System::Object

The source of the event.

e
Type: System::ConsoleCancelEventArgs

A System::ConsoleCancelEventArgs object that contains the event data.

When you create a ConsoleCancelEventHandler delegate, you identify the method that will handle the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event-handler delegates, see Events and Delegates.

The following code example demonstrates how to use the ConsoleCancelEventHandler class to handle an event.

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

.NET Framework

Supported in: 4.5.1, 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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