Timer.Enabled Propiedad
Definición
Importante
Parte de la información hace referencia a la versión preliminar del producto, que puede haberse modificado sustancialmente antes de lanzar la versión definitiva. Microsoft no otorga ninguna garantía, explícita o implícita, con respecto a la información proporcionada aquí.
public:
property bool Enabled { bool get(); void set(bool value); };
public bool Enabled { get; set; }
[System.Timers.TimersDescription("TimerEnabled")]
public bool Enabled { get; set; }
member this.Enabled : bool with get, set
[<System.Timers.TimersDescription("TimerEnabled")>]
member this.Enabled : bool with get, set
Public Property Enabled As Boolean
Valor de propiedad
Es true
si Timer debe generar el evento Elapsed; en caso contrario, es false
. De manera predeterminada, es false
.
- Atributos
Excepciones
No se puede establecer esta propiedad porque se ha desechado el temporizador.
La Interval propiedad se estableció en un valor mayor que Int32.MaxValue antes de habilitar el temporizador.
Ejemplos
En el ejemplo siguiente se crea una instancia de un Timer objeto que desencadena su Timer.Elapsed evento cada dos segundos (2000 milisegundos), se configura un controlador de eventos para el evento y se inicia el temporizador. El controlador de eventos muestra el valor de la ElapsedEventArgs.SignalTime propiedad cada vez que se genera.
using namespace System;
using namespace System::Timers;
public ref class Example
{
private:
static System::Timers::Timer^ aTimer;
public:
static void Demo()
{
// Create a timer and set a two second interval.
aTimer = gcnew System::Timers::Timer();
aTimer->Interval = 2000;
// Hook up the Elapsed event for the timer.
aTimer->Elapsed += gcnew System::Timers::ElapsedEventHandler(Example::OnTimedEvent);
// Have the timer fire repeated events (true is the default)
aTimer->AutoReset = true;
// Start the timer
aTimer->Enabled = true;
Console::WriteLine("Press the Enter key to exit the program at any time... ");
Console::ReadLine();
}
private:
static void OnTimedEvent(Object^ source, System::Timers::ElapsedEventArgs^ e)
{
Console::WriteLine("The Elapsed event was raised at {0}", e->SignalTime);
}
};
int main()
{
Example::Demo();
}
// The example displays output like the following:
// Press the Enter key to exit the program at any time...
// The Elapsed event was raised at 5/20/2015 8:48:58 PM
// The Elapsed event was raised at 5/20/2015 8:49:00 PM
// The Elapsed event was raised at 5/20/2015 8:49:02 PM
// The Elapsed event was raised at 5/20/2015 8:49:04 PM
// The Elapsed event was raised at 5/20/2015 8:49:06 PM
using System;
using System.Timers;
public class Example
{
private static Timer aTimer;
public static void Main()
{
// Create a timer and set a two second interval.
aTimer = new System.Timers.Timer();
aTimer.Interval = 2000;
// Hook up the Elapsed event for the timer.
aTimer.Elapsed += OnTimedEvent;
// Have the timer fire repeated events (true is the default)
aTimer.AutoReset = true;
// Start the timer
aTimer.Enabled = true;
Console.WriteLine("Press the Enter key to exit the program at any time... ");
Console.ReadLine();
}
private static void OnTimedEvent(Object source, System.Timers.ElapsedEventArgs e)
{
Console.WriteLine("The Elapsed event was raised at {0}", e.SignalTime);
}
}
// The example displays output like the following:
// Press the Enter key to exit the program at any time...
// The Elapsed event was raised at 5/20/2015 8:48:58 PM
// The Elapsed event was raised at 5/20/2015 8:49:00 PM
// The Elapsed event was raised at 5/20/2015 8:49:02 PM
// The Elapsed event was raised at 5/20/2015 8:49:04 PM
// The Elapsed event was raised at 5/20/2015 8:49:06 PM
open System.Timers
let onTimedEvent source (e: ElapsedEventArgs) =
printfn $"The Elapsed event was raised at {e.SignalTime}"
// Create a timer and set a two second interval.
let aTimer = new Timer()
aTimer.Interval <- 2000
// Hook up the Elapsed event for the timer.
aTimer.Elapsed.AddHandler onTimedEvent
// Have the timer fire repeated events (true is the default)
aTimer.AutoReset <- true
// Start the timer
aTimer.Enabled <- true
printfn "Press the Enter key to exit the program at any time... "
stdin.ReadLine() |> ignore
// The example displays output like the following:
// Press the Enter key to exit the program at any time...
// The Elapsed event was raised at 5/20/2015 8:48:58 PM
// The Elapsed event was raised at 5/20/2015 8:49:00 PM
// The Elapsed event was raised at 5/20/2015 8:49:02 PM
// The Elapsed event was raised at 5/20/2015 8:49:04 PM
// The Elapsed event was raised at 5/20/2015 8:49:06 PM
Imports System.Timers
Public Module Example
Private aTimer As Timer
Public Sub Main()
' Create a timer and set a two second interval.
aTimer = New System.Timers.Timer()
aTimer.Interval = 2000
' Hook up the Elapsed event for the timer.
AddHandler aTimer.Elapsed, AddressOf OnTimedEvent
' Have the timer fire repeated events (true is the default)
aTimer.AutoReset = True
' Start the timer
aTimer.Enabled = True
Console.WriteLine("Press the Enter key to exit the program at any time... ")
Console.ReadLine()
End Sub
Private Sub OnTimedEvent(source As Object, e As System.Timers.ElapsedEventArgs)
Console.WriteLine("The Elapsed event was raised at {0}", e.SignalTime)
End Sub
End Module
' The example displays output like the following:
' Press the Enter key to exit the program at any time...
' The Elapsed event was raised at 5/20/2015 8:48:58 PM
' The Elapsed event was raised at 5/20/2015 8:49:00 PM
' The Elapsed event was raised at 5/20/2015 8:49:02 PM
' The Elapsed event was raised at 5/20/2015 8:49:04 PM
' The Elapsed event was raised at 5/20/2015 8:49:06 PM
Comentarios
Establecer Enabled en true
es el mismo que llamar a Start, mientras que establecer Enabled en false
es el mismo que llamar a Stop.
Nota:
La señal para generar el Elapsed evento siempre se pone en cola para su ejecución en un ThreadPool subproceso. Esto puede dar lugar a que el Elapsed evento se genere después de establecer false
la Enabled propiedad en . El ejemplo de código del Stop método muestra una manera de solucionar esta condición de carrera.
Si Enabled se establece true
en y AutoReset se establece false
en , Timer genera el Elapsed evento una sola vez, la primera vez que transcurre el intervalo.
Si el intervalo se establece una vez Timer iniciado, se restablece el recuento. Por ejemplo, si establece el intervalo en 5 segundos y, a continuación, establece la Enabled propiedad true
en , se establece el recuento en el momento Enabled . Si restablece el intervalo a 10 segundos cuando el recuento es de 3 segundos, el Elapsed evento se genera por primera vez 13 segundos después Enabled de establecerse true
en .
Nota:
Algunos diseñadores visuales, como los de Microsoft Visual Studio, establecen la Enabled propiedad true
en al insertar un nuevo Timer.