ConsoleCancelEventArgs Class
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Provides data for the CancelKeyPress event. This class cannot be inherited.
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
- Inheritance
- Attributes
Examples
The following example demonstrates how to use the ConsoleCancelEventArgs 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
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
Remarks
A user can interrupt a console application process by simultaneously pressing the Control modifier key and the C console key (Ctrl+C), or the Control modifier key and the Break console key (Ctrl+Break). Consequently, .NET provides a ConsoleCancelEventArgs object to the event handler for the Console.CancelKeyPress event to specify whether the process should be cancelled.
If the Cancel property is set to true
in the event handler, the process is resumed; otherwise, the process is terminated. By default, the value of the ConsoleCancelEventArgs property is false
, and the process terminates.
Properties
Cancel |
Gets or sets a value that indicates whether simultaneously pressing the Control modifier key and the C console key (Ctrl+C) or the Ctrl+Break keys terminates the current process. The default is |
SpecialKey |
Gets the combination of modifier and console keys that interrupted the current process. |
Methods
Equals(Object) |
Determines whether the specified object is equal to the current object. (Inherited from Object) |
GetHashCode() |
Serves as the default hash function. (Inherited from Object) |
GetType() |
Gets the Type of the current instance. (Inherited from Object) |
MemberwiseClone() |
Creates a shallow copy of the current Object. (Inherited from Object) |
ToString() |
Returns a string that represents the current object. (Inherited from Object) |
Applies to
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