ManagementEventWatcher Construtores

Definição

Espaço de Nomes:: System.Management

Assemblagem:: System.Management.dll

Pacote:: System.Management v11.0.0-preview.4.26230.115

Importante

Algumas informações dizem respeito a um produto pré-lançado que pode ser substancialmente modificado antes de ser lançado. A Microsoft não faz garantias, de forma expressa ou implícita, em relação à informação aqui apresentada.

Inicializa uma nova instância da ManagementEventWatcher classe.

Sobrecargas

Name	Description
ManagementEventWatcher()	Inicializa uma nova instância da ManagementEventWatcher classe. Para uma inicialização adicional, defina as propriedades no objeto. Este é o construtor sem parâmetros.
ManagementEventWatcher(EventQuery)	Inicializa uma nova instância da ManagementEventWatcher classe quando recebe uma consulta de evento WMI.
ManagementEventWatcher(String)	Inicializa uma nova instância da ManagementEventWatcher classe quando recebe uma consulta de evento WMI sob a forma de uma string.
ManagementEventWatcher(ManagementScope, EventQuery)	Inicializa uma nova instância da ManagementEventWatcher classe que escuta eventos que cumprem a consulta de eventos WMI dada.
ManagementEventWatcher(String, String)	Inicializa uma nova instância da ManagementEventWatcher classe que escuta eventos que cumprem a consulta de eventos WMI dada. Para esta variante, a consulta e o âmbito são especificados como strings.
ManagementEventWatcher(ManagementScope, EventQuery, EventWatcherOptions)	Inicializa uma nova instância da ManagementEventWatcher classe que escuta eventos conformes à consulta de evento WMI dada, de acordo com as opções especificadas. Para esta variante, a consulta e o âmbito são objetos especificados. O objeto options pode especificar opções como time-out e informação de contexto.
ManagementEventWatcher(String, String, EventWatcherOptions)	Inicializa uma nova instância da ManagementEventWatcher classe que escuta eventos conformes à consulta de evento WMI dada, de acordo com as opções especificadas. Para esta variante, a consulta e o âmbito são especificados como strings. O objeto options pode especificar opções como um time-out e informação de contexto.

ManagementEventWatcher()

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Inicializa uma nova instância da ManagementEventWatcher classe. Para uma inicialização adicional, defina as propriedades no objeto. Este é o construtor sem parâmetros.

public:
 ManagementEventWatcher();

public ManagementEventWatcher();

Public Sub New ()

Exemplos

O exemplo seguinte mostra como o cliente recebe notificação quando uma instância de Win32_Process é criada porque a classe de evento é __InstanceCreationEvent. Para mais informações, consulte a documentação Windows Instrumentação de Gestão. O cliente recebe eventos de forma síncrona ao chamar o WaitForNextEvent método. Este exemplo pode ser testado iniciando um processo, como o Notepad, enquanto o código de exemplo está a correr.

using System;
using System.Management;

// This example shows synchronous consumption of events.
// The client is blocked while waiting for events.

public class EventWatcherPolling
{
    public static int Main(string[] args)
    {
        // Create event query to be notified within 1 second of
        // a change in a service
        WqlEventQuery query =
            new WqlEventQuery("__InstanceCreationEvent",
            new TimeSpan(0,0,1),
            "TargetInstance isa \"Win32_Process\"");

        // Initialize an event watcher and subscribe to events
        // that match this query
        ManagementEventWatcher watcher =
            new ManagementEventWatcher();
        watcher.Query = query;
        // times out watcher.WaitForNextEvent in 5 seconds
        watcher.Options.Timeout = new TimeSpan(0,0,5);

        // Block until the next event occurs
        // Note: this can be done in a loop if waiting for
        //        more than one occurrence
        Console.WriteLine(
            "Open an application (notepad.exe) to trigger an event.");
        ManagementBaseObject e = watcher.WaitForNextEvent();

        //Display information from the event
        Console.WriteLine(
            "Process {0} has been created, path is: {1}",
            ((ManagementBaseObject)e
            ["TargetInstance"])["Name"],
            ((ManagementBaseObject)e
            ["TargetInstance"])["ExecutablePath"]);

        //Cancel the subscription
        watcher.Stop();
        return 0;
    }
}

Imports System.Management

' This example shows synchronous consumption of events. 
' The client is blocked while waiting for events. 

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

        ' Create event query to be notified within 1 second of 
        ' a change in a service
        Dim query As New WqlEventQuery( _
            "__InstanceCreationEvent", _
            New TimeSpan(0, 0, 1), _
            "TargetInstance isa ""Win32_Process""")

        ' Initialize an event watcher and subscribe to events 
        ' that match this query
        Dim watcher As New ManagementEventWatcher
        watcher.Query = query
        ' times watcher.WaitForNextEvent in 5 seconds
        watcher.Options.Timeout = New TimeSpan(0, 0, 5)

        ' Block until the next event occurs 
        ' Note: this can be done in a loop
        ' if waiting for more than one occurrence
        Console.WriteLine( _
          "Open an application (notepad.exe) to trigger an event.")
        Dim e As ManagementBaseObject = _
            watcher.WaitForNextEvent()

        'Display information from the event
        Console.WriteLine( _
            "Process {0} has created, path is: {1}", _
            CType(e("TargetInstance"), _
                ManagementBaseObject)("Name"), _
            CType(e("TargetInstance"), _
                ManagementBaseObject)("ExecutablePath"))

        'Cancel the subscription
        watcher.Stop()
        Return 0

    End Function 'Main
End Class

Observações

Segurança do .NET Framework

Confiança total no contacto imediato. Este membro não pode ser utilizado por código parcialmente confiável. Para mais informações, consulte Utilização de Bibliotecas de Código Parcialmente Confiável.

Aplica-se a

ManagementEventWatcher(EventQuery)

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Inicializa uma nova instância da ManagementEventWatcher classe quando recebe uma consulta de evento WMI.

public:
 ManagementEventWatcher(System::Management::EventQuery ^ query);

public ManagementEventWatcher(System.Management.EventQuery query);

new System.Management.ManagementEventWatcher : System.Management.EventQuery -> System.Management.ManagementEventWatcher

Public Sub New (query As EventQuery)

Parâmetros

query: EventQuery

Um que EventQuery representa uma consulta de evento WMI, que determina os eventos para os quais o observador irá prestar atenção.

Exemplos

Neste exemplo de código, o cliente recebe notificação quando uma instância de Win32_Process é criada porque a classe de evento é __InstanceCreationEvent. Para mais informações, consulte a documentação Windows Instrumentação de Gestão. O cliente recebe eventos de forma síncrona ao chamar o WaitForNextEvent método. Este exemplo pode ser testado iniciando um processo, como o Notepad, enquanto o código de exemplo está a correr.

using System;
using System.Management;

// This example shows synchronous consumption of events.
// The client is blocked while waiting for events.

public class EventWatcherPolling
{
    public static int Main(string[] args)
    {
        // Create event query to be notified within 1 second of
        // a change in a service
        string query =
            "SELECT * FROM __InstanceCreationEvent "
            + "WITHIN 1 WHERE " +
            "TargetInstance isa \"Win32_Process\"";

        // Initialize an event watcher and subscribe to events
        // that match this query
        ManagementEventWatcher watcher =
            new ManagementEventWatcher(new EventQuery(query));

        // times out watcher.WaitForNextEvent in 5 seconds
        watcher.Options.Timeout = new TimeSpan(0,0,5);

        // Block until the next event occurs
        // Note: this can be done in a loop if waiting for
        //        more than one occurrence
        Console.WriteLine(
            "Open an application (notepad.exe) to trigger an event.");
        ManagementBaseObject e = watcher.WaitForNextEvent();

        //Display information from the event
        Console.WriteLine(
            "Process {0} has been created, path is: {1}",
            ((ManagementBaseObject)e
            ["TargetInstance"])["Name"],
            ((ManagementBaseObject)e
            ["TargetInstance"])["ExecutablePath"]);

        //Cancel the subscription
        watcher.Stop();
        return 0;
    }
}

Imports System.Management

' This example shows synchronous consumption of events. 
' The client is blocked while waiting for events. 

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

        ' Create event query to be notified within 1 second of 
        ' a change in a service
        Dim query As String
        query = "SELECT * FROM __InstanceCreationEvent " _
            & "WITHIN 1 WHERE " & _
            "TargetInstance isa ""Win32_Process"""

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

        ' times watcher.WaitForNextEvent in 5 seconds
        watcher.Options.Timeout = New TimeSpan(0, 0, 5)

        ' Block until the next event occurs 
        ' Note: this can be done in a loop
        ' if waiting for more than one occurrence
        Console.WriteLine( _
          "Open an application (notepad.exe) to trigger an event.")
        Dim e As ManagementBaseObject = _
            watcher.WaitForNextEvent()

        'Display information from the event
        Console.WriteLine( _
            "Process {0} has created, path is: {1}", _
            CType(e("TargetInstance"), _
                ManagementBaseObject)("Name"), _
            CType(e("TargetInstance"), _
                ManagementBaseObject)("ExecutablePath"))

        'Cancel the subscription
        watcher.Stop()
        Return 0

    End Function 'Main
End Class

Observações

O namespace onde o observador irá ouvir eventos é o namespace padrão que está atualmente definido.

Segurança do .NET Framework

Aplica-se a

ManagementEventWatcher(String)

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Inicializa uma nova instância da ManagementEventWatcher classe quando recebe uma consulta de evento WMI sob a forma de uma string.

public:
 ManagementEventWatcher(System::String ^ query);

public ManagementEventWatcher(string query);

new System.Management.ManagementEventWatcher : string -> System.Management.ManagementEventWatcher

Public Sub New (query As String)

Parâmetros

query: String

Uma consulta de evento WMI, que define os eventos para os quais o observador irá ouvir.

Exemplos

using System;
using System.Management;

// This example shows synchronous consumption of events.
// The client is blocked while waiting for events.

public class EventWatcherPolling
{
    public static int Main(string[] args)
    {
        // Create event query to be notified within 1 second of
        // a change in a service
        string query =
            "SELECT * FROM __InstanceCreationEvent "
            + "WITHIN 1 WHERE " +
            "TargetInstance isa \"Win32_Process\"";

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

        // times out watcher.WaitForNextEvent in 5 seconds
        watcher.Options.Timeout = new TimeSpan(0,0,5);

        // Block until the next event occurs
        // Note: this can be done in a loop if waiting for
        //        more than one occurrence
        Console.WriteLine(
            "Open an application (notepad.exe) to trigger an event.");
        ManagementBaseObject e = watcher.WaitForNextEvent();

        //Display information from the event
        Console.WriteLine(
            "Process {0} has been created, path is: {1}",
            ((ManagementBaseObject)e
            ["TargetInstance"])["Name"],
            ((ManagementBaseObject)e
            ["TargetInstance"])["ExecutablePath"]);

        //Cancel the subscription
        watcher.Stop();
        return 0;
    }
}

Imports System.Management

' This example shows synchronous consumption of events. 
' The client is blocked while waiting for events. 

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

        ' Create event query to be notified within 1 second of 
        ' a change in a service
        Dim query As String
        query = "SELECT * FROM __InstanceCreationEvent " _
            & "WITHIN 1 WHERE " & _
            "TargetInstance isa ""Win32_Process"""

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

        ' times watcher.WaitForNextEvent in 5 seconds
        watcher.Options.Timeout = New TimeSpan(0, 0, 5)

        ' Block until the next event occurs 
        ' Note: this can be done in a loop
        ' if waiting for more than one occurrence
        Console.WriteLine( _
          "Open an application (notepad.exe) to trigger an event.")
        Dim e As ManagementBaseObject = _
            watcher.WaitForNextEvent()

        'Display information from the event
        Console.WriteLine( _
            "Process {0} has created, path is: {1}", _
            CType(e("TargetInstance"), _
                ManagementBaseObject)("Name"), _
            CType(e("TargetInstance"), _
                ManagementBaseObject)("ExecutablePath"))

        'Cancel the subscription
        watcher.Stop()
        Return 0

    End Function 'Main
End Class

Observações

O namespace onde o observador irá ouvir eventos é o namespace padrão que está atualmente definido.

Segurança do .NET Framework

Aplica-se a

ManagementEventWatcher(ManagementScope, EventQuery)

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Inicializa uma nova instância da ManagementEventWatcher classe que escuta eventos que cumprem a consulta de eventos WMI dada.

public:
 ManagementEventWatcher(System::Management::ManagementScope ^ scope, System::Management::EventQuery ^ query);

public ManagementEventWatcher(System.Management.ManagementScope scope, System.Management.EventQuery query);

new System.Management.ManagementEventWatcher : System.Management.ManagementScope * System.Management.EventQuery -> System.Management.ManagementEventWatcher

Public Sub New (scope As ManagementScope, query As EventQuery)

Parâmetros

scope: ManagementScope

A representa ManagementScope o âmbito (namespace) em que o observador irá ouvir eventos.

query: EventQuery

Um que EventQuery representa uma consulta de evento WMI, que determina os eventos para os quais o observador irá prestar atenção.

Exemplos

using System;
using System.Management;

// This example shows synchronous consumption of events.
// The client is blocked while waiting for events.

public class EventWatcherPolling
{
    public static int Main(string[] args)
    {
        // Create event query to be notified within 1 second of
        // a change in a service
        string query =
            "SELECT * FROM __InstanceCreationEvent "
            + "WITHIN 1 WHERE " +
            "TargetInstance isa \"Win32_Process\"";

        // Initialize an event watcher and subscribe to events
        // that match this query
        ManagementEventWatcher watcher =
            new ManagementEventWatcher(
            new ManagementScope("root\\CIMV2"),
            new EventQuery(query));

        // times out watcher.WaitForNextEvent in 5 seconds
        watcher.Options.Timeout = new TimeSpan(0,0,5);

        // Block until the next event occurs
        // Note: this can be done in a loop if waiting for
        //        more than one occurrence
        Console.WriteLine(
            "Open an application (notepad.exe) to trigger an event.");
        ManagementBaseObject e = watcher.WaitForNextEvent();

        //Display information from the event
        Console.WriteLine(
            "Process {0} has been created, path is: {1}",
            ((ManagementBaseObject)e
            ["TargetInstance"])["Name"],
            ((ManagementBaseObject)e
            ["TargetInstance"])["ExecutablePath"]);

        //Cancel the subscription
        watcher.Stop();
        return 0;
    }
}

Imports System.Management

' This example shows synchronous consumption of events. 
' The client is blocked while waiting for events. 

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

        ' Create event query to be notified within 1 second of 
        ' a change in a service
        Dim query As String
        query = "SELECT * FROM __InstanceCreationEvent " _
            & "WITHIN 1 WHERE " & _
            "TargetInstance isa ""Win32_Process"""

        ' Initialize an event watcher and subscribe to events 
        ' that match this query
        Dim watcher As New ManagementEventWatcher( _
            New ManagementScope("root\CIMV2"), _
            New EventQuery(query))

        ' times watcher.WaitForNextEvent in 5 seconds
        watcher.Options.Timeout = New TimeSpan(0, 0, 5)

        ' Block until the next event occurs 
        ' Note: this can be done in a loop
        ' if waiting for more than one occurrence
        Console.WriteLine( _
          "Open an application (notepad.exe) to trigger an event.")
        Dim e As ManagementBaseObject = _
            watcher.WaitForNextEvent()

        'Display information from the event
        Console.WriteLine( _
            "Process {0} has created, path is: {1}", _
            CType(e("TargetInstance"), _
                ManagementBaseObject)("Name"), _
            CType(e("TargetInstance"), _
                ManagementBaseObject)("ExecutablePath"))

        'Cancel the subscription
        watcher.Stop()
        Return 0

    End Function 'Main
End Class

Observações

Segurança do .NET Framework

Aplica-se a

ManagementEventWatcher(String, String)

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Inicializa uma nova instância da ManagementEventWatcher classe que escuta eventos que cumprem a consulta de eventos WMI dada. Para esta variante, a consulta e o âmbito são especificados como strings.

public:
 ManagementEventWatcher(System::String ^ scope, System::String ^ query);

public ManagementEventWatcher(string scope, string query);

new System.Management.ManagementEventWatcher : string * string -> System.Management.ManagementEventWatcher

Public Sub New (scope As String, query As String)

Parâmetros

scope: String

O âmbito de gestão (namespace) em que o observador vai ouvir os acontecimentos.

query: String

A consulta que define os eventos para os quais o observador irá ouvir.

Exemplos

using System;
using System.Management;

// This example shows synchronous consumption of events.
// The client is blocked while waiting for events.

public class EventWatcherPolling
{
    public static int Main(string[] args)
    {
        // Create event query to be notified within 1 second of
        // a change in a service
        string query =
            "SELECT * FROM __InstanceCreationEvent "
            + "WITHIN 1 WHERE " +
            "TargetInstance isa \"Win32_Process\"";

        // Initialize an event watcher and subscribe to events
        // that match this query
        ManagementEventWatcher watcher =
            new ManagementEventWatcher("root\\CIMV2",
            query);

        // times out watcher.WaitForNextEvent in 5 seconds
        watcher.Options.Timeout = new TimeSpan(0,0,5);

        // Block until the next event occurs
        // Note: this can be done in a loop if waiting for
        //        more than one occurrence
        Console.WriteLine(
            "Open an application (notepad.exe) to trigger an event.");
        ManagementBaseObject e = watcher.WaitForNextEvent();

        //Display information from the event
        Console.WriteLine(
            "Process {0} has been created, path is: {1}",
            ((ManagementBaseObject)e
            ["TargetInstance"])["Name"],
            ((ManagementBaseObject)e
            ["TargetInstance"])["ExecutablePath"]);

        //Cancel the subscription
        watcher.Stop();
        return 0;
    }
}

Imports System.Management

' This example shows synchronous consumption of events. 
' The client is blocked while waiting for events. 

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

        ' Create event query to be notified within 1 second of 
        ' a change in a service
        Dim query As String
        query = "SELECT * FROM __InstanceCreationEvent " _
            & "WITHIN 1 WHERE " & _
            "TargetInstance isa ""Win32_Process"""

        ' Initialize an event watcher and subscribe to events 
        ' that match this query
        Dim watcher As New ManagementEventWatcher( _
            "root\CIMV2", query)

        ' times watcher.WaitForNextEvent in 5 seconds
        watcher.Options.Timeout = New TimeSpan(0, 0, 5)

        ' Block until the next event occurs 
        ' Note: this can be done in a loop
        ' if waiting for more than one occurrence
        Console.WriteLine( _
          "Open an application (notepad.exe) to trigger an event.")
        Dim e As ManagementBaseObject = _
            watcher.WaitForNextEvent()

        'Display information from the event
        Console.WriteLine( _
            "Process {0} has created, path is: {1}", _
            CType(e("TargetInstance"), _
                ManagementBaseObject)("Name"), _
            CType(e("TargetInstance"), _
                ManagementBaseObject)("ExecutablePath"))

        'Cancel the subscription
        watcher.Stop()
        Return 0

    End Function 'Main
End Class

Observações

Segurança do .NET Framework

Aplica-se a

ManagementEventWatcher(ManagementScope, EventQuery, EventWatcherOptions)

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Inicializa uma nova instância da ManagementEventWatcher classe que escuta eventos conformes à consulta de evento WMI dada, de acordo com as opções especificadas. Para esta variante, a consulta e o âmbito são objetos especificados. O objeto options pode especificar opções como time-out e informação de contexto.

public:
 ManagementEventWatcher(System::Management::ManagementScope ^ scope, System::Management::EventQuery ^ query, System::Management::EventWatcherOptions ^ options);

public ManagementEventWatcher(System.Management.ManagementScope scope, System.Management.EventQuery query, System.Management.EventWatcherOptions options);

new System.Management.ManagementEventWatcher : System.Management.ManagementScope * System.Management.EventQuery * System.Management.EventWatcherOptions -> System.Management.ManagementEventWatcher

Public Sub New (scope As ManagementScope, query As EventQuery, options As EventWatcherOptions)

Parâmetros

scope: ManagementScope

A representa ManagementScope o âmbito (namespace) em que o observador irá ouvir eventos.

query: EventQuery

Um que EventQuery representa uma consulta de evento WMI, que determina os eventos para os quais o observador irá prestar atenção.

options: EventWatcherOptions

Um EventWatcherOptions representa opções adicionais usadas para observar eventos.

Exemplos

using System;
using System.Management;

// This example shows synchronous consumption of events.
// The client is blocked while waiting for events.

public class EventWatcherPolling
{
    public static int Main(string[] args)
    {
        // Create event query to be notified within 1 second of
        // a change in a service
        string query =
            "SELECT * FROM __InstanceCreationEvent "
            + "WITHIN 1 WHERE " +
            "TargetInstance isa \"Win32_Process\"";

        // Event options
        // blockSize = 1, so wait for 1 event to return
        EventWatcherOptions options = new EventWatcherOptions(
            null, TimeSpan.MaxValue, 1);

        // Initialize an event watcher and subscribe to events
        // that match this query
        ManagementEventWatcher watcher =
            new ManagementEventWatcher(
            new ManagementScope("root\\CIMV2"),
            new EventQuery(query), options);

        // Block until the next event occurs
        // Note: this can be done in a loop if waiting for
        //        more than one occurrence
        Console.WriteLine(
            "Open an application (notepad.exe) to trigger an event.");
        ManagementBaseObject e = watcher.WaitForNextEvent();

        //Display information from the event
        Console.WriteLine(
            "Process {0} has been created, path is: {1}",
            ((ManagementBaseObject)e
            ["TargetInstance"])["Name"],
            ((ManagementBaseObject)e
            ["TargetInstance"])["ExecutablePath"]);

        //Cancel the subscription
        watcher.Stop();
        return 0;
    }
}

Imports System.Management

' This example shows synchronous consumption of events. 
' The client is blocked while waiting for events. 

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

        ' Create event query to be notified within 1 second of 
        ' a change in a service
        Dim query As String
        query = "SELECT * FROM __InstanceCreationEvent " _
            & "WITHIN 1 WHERE " & _
            "TargetInstance isa ""Win32_Process"""

        ' Event options
        ' blockSize = 1, so wait for 1 event to return
        Dim options As New EventWatcherOptions( _
            Nothing, TimeSpan.MaxValue, 1)


        ' Initialize an event watcher and subscribe to events 
        ' that match this query
        Dim watcher As New ManagementEventWatcher( _
            New ManagementScope("root\CIMV2"), _
            New EventQuery(query), _
            options)

        ' Block until the next event occurs 
        ' Note: this can be done in a loop
        ' if waiting for more than one occurrence
        Console.WriteLine( _
          "Open an application (notepad.exe) to trigger an event.")
        Dim e As ManagementBaseObject = _
            watcher.WaitForNextEvent()

        'Display information from the event
        Console.WriteLine( _
            "Process {0} has created, path is: {1}", _
            CType(e("TargetInstance"), _
                ManagementBaseObject)("Name"), _
            CType(e("TargetInstance"), _
                ManagementBaseObject)("ExecutablePath"))

        'Cancel the subscription
        watcher.Stop()
        Return 0

    End Function 'Main
End Class

Observações

Segurança do .NET Framework

Aplica-se a

ManagementEventWatcher(String, String, EventWatcherOptions)

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Origem:: ManagementEventWatcher.cs

Inicializa uma nova instância da ManagementEventWatcher classe que escuta eventos conformes à consulta de evento WMI dada, de acordo com as opções especificadas. Para esta variante, a consulta e o âmbito são especificados como strings. O objeto options pode especificar opções como um time-out e informação de contexto.

public:
 ManagementEventWatcher(System::String ^ scope, System::String ^ query, System::Management::EventWatcherOptions ^ options);

public ManagementEventWatcher(string scope, string query, System.Management.EventWatcherOptions options);

new System.Management.ManagementEventWatcher : string * string * System.Management.EventWatcherOptions -> System.Management.ManagementEventWatcher

Public Sub New (scope As String, query As String, options As EventWatcherOptions)

Parâmetros

scope: String

O âmbito de gestão (namespace) em que o observador vai ouvir os acontecimentos.

query: String

A consulta que define os eventos para os quais o observador irá ouvir.

options: EventWatcherOptions

Um EventWatcherOptions representa opções adicionais usadas para observar eventos.

Exemplos

using System;
using System.Management;

// This example shows synchronous consumption of events.
// The client is blocked while waiting for events.

public class EventWatcherPolling
{
    public static int Main(string[] args)
    {
        // Create event query to be notified within 1 second of
        // a change in a service
        string query =
            "SELECT * FROM __InstanceCreationEvent "
            + "WITHIN 1 WHERE " +
            "TargetInstance isa \"Win32_Process\"";

        // Event options
        // blockSize = 1, so wait for 1 event to return
        EventWatcherOptions options = new EventWatcherOptions(
            null, TimeSpan.MaxValue, 1);

        // Initialize an event watcher and subscribe to events
        // that match this query
        ManagementEventWatcher watcher =
            new ManagementEventWatcher(
            new ManagementScope("root\\CIMV2"),
            new EventQuery(query), options);

        // Block until the next event occurs
        // Note: this can be done in a loop if waiting for
        //        more than one occurrence
        Console.WriteLine(
            "Open an application (notepad.exe) to trigger an event.");
        ManagementBaseObject e = watcher.WaitForNextEvent();

        //Display information from the event
        Console.WriteLine(
            "Process {0} has been created, path is: {1}",
            ((ManagementBaseObject)e
            ["TargetInstance"])["Name"],
            ((ManagementBaseObject)e
            ["TargetInstance"])["ExecutablePath"]);

        //Cancel the subscription
        watcher.Stop();
        return 0;
    }
}

Imports System.Management

' This example shows synchronous consumption of events. 
' The client is blocked while waiting for events. 

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

        ' Create event query to be notified within 1 second of 
        ' a change in a service
        Dim query As String
        query = "SELECT * FROM __InstanceCreationEvent " _
            & "WITHIN 1 WHERE " & _
            "TargetInstance isa ""Win32_Process"""

        ' Event options
        ' blockSize = 1, so wait for 1 event to return
        Dim options As New EventWatcherOptions( _
            Nothing, TimeSpan.MaxValue, 1)


        ' Initialize an event watcher and subscribe to events 
        ' that match this query
        Dim watcher As New ManagementEventWatcher( _
            "root\CIMV2", _
            query, _
            options)

        ' Block until the next event occurs 
        ' Note: this can be done in a loop
        ' if waiting for more than one occurrence
        Console.WriteLine( _
          "Open an application (notepad.exe) to trigger an event.")
        Dim e As ManagementBaseObject = _
            watcher.WaitForNextEvent()

        'Display information from the event
        Console.WriteLine( _
            "Process {0} has created, path is: {1}", _
            CType(e("TargetInstance"), _
                ManagementBaseObject)("Name"), _
            CType(e("TargetInstance"), _
                ManagementBaseObject)("ExecutablePath"))

        'Cancel the subscription
        watcher.Stop()
        Return 0

    End Function 'Main
End Class

Observações

Segurança do .NET Framework

Aplica-se a

Comentários

Esta página foi útil?