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ManagementOperationObserver.ObjectReady Event

Occurs when a new object is available.

Namespace:  System.Management
Assembly:  System.Management (in System.Management.dll)

Public Event ObjectReady As ObjectReadyEventHandler

Event Data

The event handler receives an argument of type ObjectReadyEventArgs containing data related to this event. The following ObjectReadyEventArgs properties provide information specific to this event.



Context (inherited from ManagementEventArgs)

Gets the operation context echoed back from the operation that triggered the event.


Gets the newly-returned object.

.NET Framework Security

Full trust for the immediate caller. This member cannot be used by partially trusted code. For more information, see Using Libraries from Partially Trusted Code.

The following example demonstrates how to perform an asynchronous instance enumeration. The example uses the ManagementOperationObserver class to handle management information and events asynchronously.

Imports System
Imports System.Management

' This example demonstrates how
' to perform an asynchronous instance enumeration.

Public Class EnumerateInstancesAsync

    Public Sub New()

        Me.isCompleted = False

        ' Enumerate asynchronously using Object Searcher
        ' ===============================================

        ' Instantiate an object searcher with the query
        Dim searcher As ManagementObjectSearcher
        searcher = New ManagementObjectSearcher( _
            New SelectQuery("Win32_Service"))

        ' Create a results watcher object, 
        ' and handler for results and completion
        Dim results As ManagementOperationObserver
        results = New ManagementOperationObserver

        ' Attach handler to events for
        ' results and completion
        AddHandler results.ObjectReady, _
            AddressOf Me.NewObject
        AddHandler results.Completed, _
            AddressOf Me.Done

        ' Call the asynchronous overload of
        ' Get() to start the enumeration

        ' Do something else while results 
        ' arrive(asynchronously)
        Do While (Me.Completed.Equals(False))



    End Sub

    Private isCompleted As Boolean

    Private Sub NewObject(ByVal sender As Object, _
        ByVal e As ObjectReadyEventArgs)

        Console.WriteLine("Service : {0}, State = {1}", _
         e.NewObject("Name"), e.NewObject("State"))
    End Sub

    Private ReadOnly Property Completed() As Boolean
            Return isCompleted
        End Get
    End Property

    Private Sub Reset()

        isCompleted = False
    End Sub

    Private Sub Done(ByVal sender As Object, _
        ByVal e As CompletedEventArgs)

        isCompleted = True
    End Sub

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

        Dim example As New EnumerateInstancesAsync

        Return 0

    End Function

End Class

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.