EventArgs Clase

Definición

Representa la clase base para las clases que contienen datos de eventos, y proporciona un valor que se utilizará para eventos que no incluyen datos de eventos.Represents the base class for classes that contain event data, and provides a value to use for events that do not include event data.

public ref class EventArgs
[System.Runtime.InteropServices.ComVisible(true)]
[System.Serializable]
public class EventArgs
type EventArgs = class
Public Class EventArgs
Herencia
EventArgs
Derivado
Atributos

Ejemplos

En el ejemplo siguiente se muestra una clase de datos de evento personalizada denominada ThresholdReachedEventArgs que deriva de la clase EventArgs.The following example shows a custom event data class named ThresholdReachedEventArgs that derives from the EventArgs class. Se pasa una instancia de la clase de datos de evento al controlador de eventos para el evento ThresholdReached.An instance of the event data class is passed to the event handler for the ThresholdReached event.

using namespace System;

public ref class ThresholdReachedEventArgs : public EventArgs
{
   public:
      property int Threshold;
      property DateTime TimeReached;
};

public ref class Counter
{
   private:
      int threshold;
      int total;

   public:
      Counter() {};

      Counter(int passedThreshold)
      {
         threshold = passedThreshold;
      }

      void Add(int x)
      {
          total += x;
          if (total >= threshold) {
             ThresholdReachedEventArgs^ args = gcnew ThresholdReachedEventArgs();
             args->Threshold = threshold;
             args->TimeReached = DateTime::Now;
             OnThresholdReached(args);
          }
      }

      event EventHandler<ThresholdReachedEventArgs^>^ ThresholdReached;

   protected:
      virtual void OnThresholdReached(ThresholdReachedEventArgs^ e)
      {
         ThresholdReached(this, e);
      }
};

public ref class SampleHandler
{
   public:
      static void c_ThresholdReached(Object^ sender, ThresholdReachedEventArgs^ e)
      {
         Console::WriteLine("The threshold of {0} was reached at {1}.",
                            e->Threshold,  e->TimeReached);
         Environment::Exit(0);
      }
};

void main()
{
   Counter^ c = gcnew Counter((gcnew Random())->Next(10));
   c->ThresholdReached += gcnew EventHandler<ThresholdReachedEventArgs^>(SampleHandler::c_ThresholdReached);

   Console::WriteLine("press 'a' key to increase total");
   while (Console::ReadKey(true).KeyChar == 'a') {
      Console::WriteLine("adding one");
      c->Add(1);
   }
}
using System;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            Counter c = new Counter(new Random().Next(10));
            c.ThresholdReached += c_ThresholdReached;

            Console.WriteLine("press 'a' key to increase total");
            while (Console.ReadKey(true).KeyChar == 'a')
            {
                Console.WriteLine("adding one");
                c.Add(1);
            }
        }

        static void c_ThresholdReached(object sender, ThresholdReachedEventArgs e)
        {
            Console.WriteLine("The threshold of {0} was reached at {1}.", e.Threshold,  e.TimeReached);
            Environment.Exit(0);
        }
    }

    class Counter
    {
        private int threshold;
        private int total;

        public Counter(int passedThreshold)
        {
            threshold = passedThreshold;
        }

        public void Add(int x)
        {
            total += x;
            if (total >= threshold)
            {
                ThresholdReachedEventArgs args = new ThresholdReachedEventArgs();
                args.Threshold = threshold;
                args.TimeReached = DateTime.Now;
                OnThresholdReached(args);
            }
        }

        protected virtual void OnThresholdReached(ThresholdReachedEventArgs e)
        {
            EventHandler<ThresholdReachedEventArgs> handler = ThresholdReached;
            if (handler != null)
            {
                handler(this, e);
            }
        }

        public event EventHandler<ThresholdReachedEventArgs> ThresholdReached;
    }

    public class ThresholdReachedEventArgs : EventArgs
    {
        public int Threshold { get; set; }
        public DateTime TimeReached { get; set; }
    }
}
Module Module1

    Sub Main()
        Dim c As Counter = New Counter(New Random().Next(10))
        AddHandler c.ThresholdReached, AddressOf c_ThresholdReached

        Console.WriteLine("press 'a' key to increase total")
        While Console.ReadKey(True).KeyChar = "a"
            Console.WriteLine("adding one")
            c.Add(1)
        End While
    End Sub

    Sub c_ThresholdReached(sender As Object, e As ThresholdReachedEventArgs)
        Console.WriteLine("The threshold of {0} was reached at {1}.", e.Threshold, e.TimeReached)
        Environment.Exit(0)
    End Sub
End Module

Class Counter
    Private threshold As Integer
    Private total As Integer

    Public Sub New(passedThreshold As Integer)
        threshold = passedThreshold
    End Sub

    Public Sub Add(x As Integer)
        total = total + x
        If (total >= threshold) Then
            Dim args As ThresholdReachedEventArgs = New ThresholdReachedEventArgs()
            args.Threshold = threshold
            args.TimeReached = DateTime.Now
            OnThresholdReached(args)
        End If
    End Sub

    Protected Overridable Sub OnThresholdReached(e As ThresholdReachedEventArgs)
        RaiseEvent ThresholdReached(Me, e)
    End Sub

    Public Event ThresholdReached As EventHandler(Of ThresholdReachedEventArgs)
End Class

Class ThresholdReachedEventArgs
    Inherits EventArgs

    Public Property Threshold As Integer
    Public Property TimeReached As DateTime
End Class

Comentarios

Esta clase actúa como la clase base para todas las clases que representan los datos de evento.This class serves as the base class for all classes that represent event data. Por ejemplo, la clase System.AssemblyLoadEventArgs deriva de EventArgs y se utiliza para almacenar los datos de los eventos de carga de ensamblado.For example, the System.AssemblyLoadEventArgs class derives from EventArgs and is used to hold the data for assembly load events. Para crear una clase de datos de evento personalizada, cree una clase que derive de la clase EventArgs y proporcione las propiedades para almacenar los datos necesarios.To create a custom event data class, create a class that derives from the EventArgs class and provide the properties to store the necessary data. El nombre de la clase de datos de evento personalizado debe terminar en EventArgs.The name of your custom event data class should end with EventArgs.

Para pasar un objeto que no contiene ningún dato, use el campo Empty.To pass an object that does not contain any data, use the Empty field.

Para obtener más información sobre los eventos, consulte el artículo control y generación de eventos .For more information about events, see the Handling and Raising Events article.

Constructores

EventArgs()

Inicializa una nueva instancia de la clase EventArgs.Initializes a new instance of the EventArgs class.

Campos

Empty

Proporciona un valor para utilizar con los eventos que no tienen datos de eventos.Provides a value to use with events that do not have event data.

Métodos

Equals(Object)

Determina si el objeto especificado es igual al objeto actual.Determines whether the specified object is equal to the current object.

(Heredado de Object)
GetHashCode()

Sirve como función hash predeterminada.Serves as the default hash function.

(Heredado de Object)
GetType()

Obtiene el Type de la instancia actual.Gets the Type of the current instance.

(Heredado de Object)
MemberwiseClone()

Crea una copia superficial del Object actual.Creates a shallow copy of the current Object.

(Heredado de Object)
ToString()

Devuelve un valor de tipo string que representa el objeto actual.Returns a string that represents the current object.

(Heredado de Object)

Se aplica a

Consulte también: