EventWatcherOptions Konstruktorer

Definition

Namnområde:: System.Management

Sammansättning:: System.Management.dll

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

Viktigt

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Initierar en ny instans av EventWatcherOptions klassen för händelsevisning.

Överlagringar

Name	Description
EventWatcherOptions()	Initierar en ny instans av klassen för händelsevisning med hjälp av EventWatcherOptions standardvärden. Det här är den parameterlösa konstruktorn.
EventWatcherOptions(ManagementNamedValueCollection, TimeSpan, Int32)	Initierar en ny instans av EventWatcherOptions klassen med angivna värden.

EventWatcherOptions()

Källa:: ManagementOptions.cs

Källa:: ManagementOptions.cs

Källa:: ManagementOptions.cs

Källa:: ManagementOptions.cs

Initierar en ny instans av klassen för händelsevisning med hjälp av EventWatcherOptions standardvärden. Det här är den parameterlösa konstruktorn.

public:
 EventWatcherOptions();

public EventWatcherOptions();

Public Sub New ()

Exempel

I följande exempel visas hur klienten får ett meddelande när en instans av Win32_Process skapas eftersom händelseklassen är __InstanceCreationEvent. Mer information finns i dokumentationen Windows Management Instrumentation. Klienten tar emot händelser synkront genom att anropa WaitForNextEvent metoden. Det här exemplet kan testas genom att starta en process, till exempel Anteckningar, medan exempelkoden körs.

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
        EventWatcherOptions eventOptions = new
            EventWatcherOptions();
        eventOptions.Timeout = System.TimeSpan.MaxValue;

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

        // 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
        Dim eventOptions As New EventWatcherOptions
        eventOptions.Timeout = System.TimeSpan.MaxValue

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

        ' 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

Kommentarer

.NET Framework-säkerhet

Fullständigt förtroende för den omedelbara uppringaren. Den här medlemmen kan inte användas av delvis betrodd kod. Mer information finns i Använda bibliotek från delvis betrodd kod.

Gäller för

EventWatcherOptions(ManagementNamedValueCollection, TimeSpan, Int32)

Källa:: ManagementOptions.cs

Källa:: ManagementOptions.cs

Källa:: ManagementOptions.cs

Källa:: ManagementOptions.cs

Initierar en ny instans av EventWatcherOptions klassen med angivna värden.

public:
 EventWatcherOptions(System::Management::ManagementNamedValueCollection ^ context, TimeSpan timeout, int blockSize);

public EventWatcherOptions(System.Management.ManagementNamedValueCollection context, TimeSpan timeout, int blockSize);

new System.Management.EventWatcherOptions : System.Management.ManagementNamedValueCollection * TimeSpan * int -> System.Management.EventWatcherOptions

Public Sub New (context As ManagementNamedValueCollection, timeout As TimeSpan, blockSize As Integer)

Parametrar

context: ManagementNamedValueCollection

Alternativkontextobjektet som innehåller providerspecifik information som ska skickas till providern.

timeout: TimeSpan

Tidsgränsen för att vänta på nästa händelser.

blockSize: Int32

Antalet händelser att vänta på i varje block.

Exempel

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 to receive one event
        EventWatcherOptions eventOptions = new
            EventWatcherOptions(null, System.TimeSpan.MaxValue,
            1);

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

        // 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 to receive one event
        Dim eventOptions As New EventWatcherOptions( _
            Nothing, System.TimeSpan.MaxValue, 1)

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

        ' 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

Kommentarer

.NET Framework-säkerhet

Fullständigt förtroende för den omedelbara uppringaren. Den här medlemmen kan inte användas av delvis betrodd kod. Mer information finns i Använda bibliotek från delvis betrodd kod.

Gäller för

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