EventArrivedEventHandler Delegate

Definition

Namespace:

System.Management

Assembly:

System.Management.dll

Package:

System.Management v9.0.0

Source:

ManagementEventWatcher.cs

Represents the method that will handle the EventArrived event.

public delegate void EventArrivedEventHandler(System::Object ^ sender, EventArrivedEventArgs ^ e);

public delegate void EventArrivedEventHandler(object sender, EventArrivedEventArgs e);

type EventArrivedEventHandler = delegate of obj * EventArrivedEventArgs -> unit

Public Delegate Sub EventArrivedEventHandler(sender As Object, e As EventArrivedEventArgs)

Parameters

sender

Object

The instance of the object for which to invoke this method.

e

EventArrivedEventArgs

The EventArrivedEventArgs that specifies the reason the event was invoked.

Examples

The following asynchronous example sets up a WMI timer to raise an event every second, and removes it when no longer needed. The ManagementEventWatcher defines several .NET Framework events which are raised when WMI events are delivered. Delegates are attached to these events for handling the incoming data.

using System;
using System.Management;

// This example shows asynchronous consumption of events.
// In this example you are listening for timer events.
// The first part of the example sets up the timer.
public class EventWatcherAsync
{
    public EventWatcherAsync()
    {
        // Set up a timer to raise events every 1 second
        //=============================================
        ManagementClass timerClass =
            new ManagementClass("__IntervalTimerInstruction");
        ManagementObject timer = timerClass.CreateInstance();
        timer["TimerId"] = "Timer1";
        timer["IntervalBetweenEvents"] = 1000;
        timer.Put();

        // Set up the event consumer
        //==========================
        // Create event query to receive timer events
        WqlEventQuery query =
            new WqlEventQuery("__TimerEvent",
            "TimerId=\"Timer1\"");

        // Initialize an event watcher and
        // subscribe to timer events
        ManagementEventWatcher watcher =
            new ManagementEventWatcher(query);

        // Set up a listener for events
        watcher.EventArrived +=
            new EventArrivedEventHandler(
            this.HandleEvent);

        // Start listening
        watcher.Start();

        // Do something in the meantime
        System.Threading.Thread.Sleep(10000);

        // Stop listening
        watcher.Stop();
    }

    private void HandleEvent(object sender,
        EventArrivedEventArgs e)
    {
        Console.WriteLine("Event arrived !");
    }

    public static void Main(string[] args)
    {
        // start the event watcher
        EventWatcherAsync eventWatcher = new
            EventWatcherAsync();
    }
}

Imports System.Management

' This example shows asynchronous consumption of events.
' In this example you are listening for timer events.
' The first part of the example sets up the timer.

Public Class EventWatcherAsync

    Public Sub New()
        ' Set up a timer to raise events every 1 second
        '=============================================
        Dim timerClass As New ManagementClass( _
            "__IntervalTimerInstruction")
        Dim timer As ManagementObject = _
            timerClass.CreateInstance()
        timer("TimerId") = "Timer1"
        timer("IntervalBetweenEvents") = 1000
        timer.Put()

        ' Set up the event consumer
        '==========================
        ' Create event query to receive timer events
        Dim query As New WqlEventQuery("__TimerEvent", _
            "TimerId=""Timer1""")

        ' Initialize an event watcher and subscribe to 
        ' events that match this query
        Dim watcher As New ManagementEventWatcher(query)

        ' Set up a listener for events
        AddHandler watcher.EventArrived, _
            AddressOf Me.HandleEvent

        ' Start listening
        watcher.Start()

        ' Do something in the meantime
        System.Threading.Thread.Sleep(10000)

        ' Stop listening
        watcher.Stop()

    End Sub

    Private Sub HandleEvent(ByVal sender As Object, _
        ByVal e As EventArrivedEventArgs)

        Console.WriteLine("Event arrived !")
    End Sub

    Public Overloads Shared Function _
            Main(ByVal args() As String) As Integer

        'start the event watcher
        Dim eventWatcher As New EventWatcherAsync

        Return 0

    End Function

End Class

Extension Methods