EventArgs Clase
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.
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.
public ref class EventArgs
public class EventArgs
[System.Serializable]
public class EventArgs
[System.Serializable]
[System.Runtime.InteropServices.ComVisible(true)]
public class EventArgs
type EventArgs = class
[<System.Serializable>]
type EventArgs = class
[<System.Serializable>]
[<System.Runtime.InteropServices.ComVisible(true)>]
type EventArgs = class
Public Class EventArgs
- Herencia
-
EventArgs
- Derivado
- Atributos
Ejemplos
En el ejemplo siguiente se muestra una clase de datos de eventos personalizada denominada ThresholdReachedEventArgs
que deriva de la EventArgs clase . Se pasa una instancia de la clase de datos de eventos al controlador de eventos para el ThresholdReached
evento.
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; }
}
}
open System
type ThresholdReachedEventArgs(threshold, timeReached) =
inherit EventArgs()
member _.Threshold = threshold
member _.TimeReached = timeReached
type Counter(threshold) =
let mutable total = 0
let thresholdReached = Event<_>()
member this.Add(x) =
total <- total + x
if total >= threshold then
let args = ThresholdReachedEventArgs(threshold, DateTime.Now)
thresholdReached.Trigger(this, args)
[<CLIEvent>]
member _.ThresholdReached = thresholdReached.Publish
let c_ThresholdReached(sender, e: ThresholdReachedEventArgs) =
printfn $"The threshold of {e.Threshold} was reached at {e.TimeReached}."
exit 0
let c = Counter(Random().Next 10)
c.ThresholdReached.Add c_ThresholdReached
printfn "press 'a' key to increase total"
while Console.ReadKey(true).KeyChar = 'a' do
printfn "adding one"
c.Add 1
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 clase base para todas las clases que representan datos de eventos. Por ejemplo, la System.AssemblyLoadEventArgs clase se deriva de EventArgs y se usa para contener los datos de los eventos de carga de ensamblados. Para crear una clase de datos de eventos personalizada, cree una clase que derive de la EventArgs clase y proporcione las propiedades para almacenar los datos necesarios. El nombre de la clase de datos de eventos personalizada debe terminar con EventArgs
.
Para pasar un objeto que no contiene ningún dato, use el Empty campo .
Para obtener más información sobre los eventos, consulte el artículo Control y generación de eventos .
Constructores
EventArgs() |
Inicializa una nueva instancia de la clase EventArgs. |
Campos
Empty |
Proporciona un valor para utilizar con los eventos que no tienen datos de eventos. |
Métodos
Equals(Object) |
Determina si el objeto especificado es igual que el objeto actual. (Heredado de Object) |
GetHashCode() |
Sirve como la función hash predeterminada. (Heredado de Object) |
GetType() |
Obtiene el Type de la instancia actual. (Heredado de Object) |
MemberwiseClone() |
Crea una copia superficial del Object actual. (Heredado de Object) |
ToString() |
Devuelve una cadena que representa el objeto actual. (Heredado de Object) |