EventWatcherOptions 建構函式
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
初始化該類別的新實例 EventWatcherOptions 以進行事件監視。
多載
| 名稱 | Description |
|---|---|
| EventWatcherOptions() |
初始化該類別的新實例 EventWatcherOptions 用於事件監視,使用預設值。 這就是無參數建構子。 |
| EventWatcherOptions(ManagementNamedValueCollection, TimeSpan, Int32) |
初始化一個新的類別實例 EventWatcherOptions ,並以給定的值。 |
EventWatcherOptions()
初始化該類別的新實例 EventWatcherOptions 用於事件監視,使用預設值。 這就是無參數建構子。
public:
EventWatcherOptions();
public EventWatcherOptions();
Public Sub New ()
範例
以下範例說明當事件類別被__InstanceCreationEvent時,客戶端如何收到Win32_Process實例的通知。 欲了解更多資訊,請參閱 Windows 管理儀器文件。 用戶端透過呼叫 WaitForNextEvent 方法同步接收事件。 此範例可透過啟動程序(如記事本)在範例程式碼執行時進行測試。
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
備註
.NET Framework 安全性
完全信任當下的來電者。 此成員無法被部分受信任的程式碼使用。 欲了解更多資訊,請參閱 「部分受信任程式碼的函式庫使用」。
適用於
EventWatcherOptions(ManagementNamedValueCollection, TimeSpan, Int32)
初始化一個新的類別實例 EventWatcherOptions ,並以給定的值。
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)
參數
- context
- ManagementNamedValueCollection
選項上下文物件包含提供者專屬資訊,需傳遞給提供者。
- timeout
- TimeSpan
等待下一件事的暫停時間。
- blockSize
- Int32
每個區塊需要等待的事件數量。
範例
以下範例說明當事件類別被__InstanceCreationEvent時,客戶端如何收到Win32_Process實例的通知。 欲了解更多資訊,請參閱 Windows 管理儀器文件。 用戶端透過呼叫 WaitForNextEvent 方法同步接收事件。 此範例可透過啟動程序(如記事本)在範例程式碼執行時進行測試。
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
備註
.NET Framework 安全性
完全信任當下的來電者。 此成員無法被部分受信任的程式碼使用。 欲了解更多資訊,請參閱 「部分受信任程式碼的函式庫使用」。