BufferedWebEventProvider 類別

定義

public ref class BufferedWebEventProvider abstract : System::Web::Management::WebEventProvider

public abstract class BufferedWebEventProvider : System.Web.Management.WebEventProvider

type BufferedWebEventProvider = class
    inherit WebEventProvider

Public MustInherit Class BufferedWebEventProvider
Inherits WebEventProvider

繼承

Object

ProviderBase

WebEventProvider

BufferedWebEventProvider

衍生

System.Web.Management.MailWebEventProvider

System.Web.Management.SqlWebEventProvider

範例

以下程式碼範例說明如何從類別 BufferedWebEventProvider 衍生出一個自訂提供者，將設定事件寫入本地檔案，必須授予適當的存取權限。

using System;
using System.Text;
using System.IO;
using System.Web.Management;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Web;

 namespace Samples.AspNet.Management
 {
    // Implements a custom event provider.
    public class SampleBufferedWebEventProvider :
        BufferedWebEventProvider
    {

        // The local path of the file where
        // to store event information.
        private string logFilePath = string.Empty;

        // Holds custom information.
        private StringBuilder customInfo;

        private FileStream fs;

        private string providerName, 
            buffer, bufferModality;

        public SampleBufferedWebEventProvider()
        {
            // Perform local initializations.

            // Path of local file where to store 
            // event info.
            // Assure that the path works for you and
            // that the right permissions are set.
            logFilePath = "C:/test/log.doc";
            
            // Instantiate buffer to contain 
            // local data.
            customInfo = new StringBuilder();
        }


        public override void  Flush()
        {
            customInfo.AppendLine("Perform custom flush");
            StoreToFile(customInfo, logFilePath, FileMode.Append);
        }

        // Initializes the provider.
        public override void Initialize(string name,
         NameValueCollection config)
        {
            base.Initialize(name, config);

            // Get the configuration information.
            providerName = name;
            buffer = SampleUseBuffering.ToString();
            bufferModality = SampleBufferMode;

            customInfo.AppendLine(string.Format(
                "Provider name: {0}", providerName));
            customInfo.AppendLine(string.Format(
                "Buffering: {0}", buffer));
            customInfo.AppendLine(string.Format(
                "Buffering modality: {0}", bufferModality));
        }

        public bool SampleUseBuffering
        {
            get { return UseBuffering; }
        }

        public string SampleBufferMode
        {
            get { return BufferMode; }
        }


        // Processes the incoming events.
        // This method performs custom processing and, 
        // if buffering is enabled, it calls the 
        // base.ProcessEvent to buffer the event
        // information.
        public override void ProcessEvent(
            WebBaseEvent eventRaised)
        {

            if (UseBuffering)
            {
                // Buffering enabled, call the 
                // base event to buffer event information.
                base.ProcessEvent(eventRaised);
            }
            else
            {
                // Buffering disabled, store the 
                // current event now.
                customInfo.AppendLine(
                    "*** Buffering disabled ***");
                customInfo.AppendLine(
                    eventRaised.ToString());
                // Store the information in the specified file.
                StoreToFile(customInfo, 
                    logFilePath, FileMode.Append);
            }
        }

        private WebBaseEventCollection GetEvents(
            WebEventBufferFlushInfo flushInfo)
        {
            return flushInfo.Events;
        }


        private int GetEventsDiscardedSinceLastNotification(
            WebEventBufferFlushInfo flushInfo)
        {
            return flushInfo.EventsDiscardedSinceLastNotification;
        }


        private int GetEventsInBuffer(
            WebEventBufferFlushInfo flushInfo)
        {
            return flushInfo.EventsInBuffer;
        }


        private DateTime GetLastNotificationTime(
            WebEventBufferFlushInfo flushInfo)
        {
            return flushInfo.LastNotificationUtc;
        }

        
        private int GetNotificationSequence(
            WebEventBufferFlushInfo flushInfo)
        {
            return flushInfo.NotificationSequence;
        }


        private EventNotificationType GetNotificationType(
            WebEventBufferFlushInfo flushInfo)
        {
            return flushInfo.NotificationType;
        }



        // Processes the messages that have been buffered.
        // It is called by the ASP.NET when the flushing of 
        // the buffer is required.
        public override void ProcessEventFlush(
            WebEventBufferFlushInfo flushInfo)
        {

            // Customize event information to be sent to 
            // the Windows Event Viewer Application Log.
            customInfo.AppendLine(
                "SampleEventLogWebEventProvider buffer flush.");

            customInfo.AppendLine(
                string.Format("NotificationType: {0}",
                GetNotificationType(flushInfo)));

            customInfo.AppendLine(
                string.Format("EventsInBuffer: {0}",
                GetEventsInBuffer(flushInfo)));

            customInfo.AppendLine(
                string.Format(
                "EventsDiscardedSinceLastNotification: {0}",
                GetEventsDiscardedSinceLastNotification(flushInfo)));

            // Read each buffered event and send it to the
            // Application Log.
            foreach (WebBaseEvent eventRaised in flushInfo.Events)
                customInfo.AppendLine(eventRaised.ToString());

            // Store the information in the specified file.
            StoreToFile(customInfo, logFilePath, FileMode.Append);
        }

        // Performs standard shutdown.
        public override void Shutdown()
        {
            // Here you need the code that performs
            // those tasks required before shutting 
            // down the provider.

            // Flush the buffer, if needed.
            Flush();
        }

        // Store event information in a local file.
        private void StoreToFile(StringBuilder text,
            string filePath, FileMode mode)
        {
            int writeBlock;
            int startIndex;

            try
            {

                writeBlock = 256;
                startIndex = 0;

                // Open or create the local file 
                // to store the event information.
                fs = new FileStream(filePath,
                    mode, FileAccess.Write);

                // Lock the file for writing.
                fs.Lock(startIndex, writeBlock);

                // Create a stream writer
                StreamWriter writer = new StreamWriter(fs);

                // Set the file pointer to the current 
                // position to keep adding data to it. 
                // If you want to rewrite the file use 
                // the following statement instead.
                // writer.BaseStream.Seek (0, SeekOrigin.Begin);
                writer.BaseStream.Seek(0, SeekOrigin.Current);

                //If the file already exists it must not 
                // be write protected otherwise  
                // the following write operation fails silently.
                writer.Write(text.ToString());

                // Update the underlying file
                writer.Flush();

                // Unlock the file for other processes.
                fs.Unlock(startIndex, writeBlock);

                // Close the stream writer and the underlying file     
                writer.Close();

                fs.Close();
            }
            catch (Exception e)
            {
                // Use this for debugging.
                // Never dispaly it!
                string ex = e.ToString();
                throw new Exception(
                    "[SampleEventProvider] StoreToFile: exception." );
            }
        }
    }
}

Imports System.Text
Imports System.IO
Imports System.Web.Management
Imports System.Collections.Generic
Imports System.Collections.Specialized
Imports System.Web



' Implements a custom event provider.

Public Class SampleBufferedWebEventProvider
   Inherits BufferedWebEventProvider
   
   ' The local path of the file where
   ' to store event information.
   Private logFilePath As String = String.Empty
   
   ' Holds custom information.
   Private customInfo As StringBuilder
   
   Private fs As FileStream
   
    Private providerName, buffer, bufferModality As String
   
   
   Public Sub New()
      ' Perform local initializations.
      ' Path of local file where to store 
      ' event info.
      ' Assure that the path works for you and
      ' that the right permissions are set.
      logFilePath = "C:/test/log.doc"
      
      ' Instantiate buffer to contain 
      ' local data.
      customInfo = New StringBuilder()
   End Sub
    
   
   Public Overrides Sub Flush()
      customInfo.AppendLine("Perform custom flush")
        StoreToFile(customInfo, _
        logFilePath, FileMode.Append)
   End Sub
   
   ' Initializes the provider.
    Public Overrides Sub Initialize(ByVal name As String, _
    ByVal config As NameValueCollection)
        MyBase.Initialize(name, config)

        ' Get the configuration information.
        providerName = name
        buffer = SampleUseBuffering.ToString()
        bufferModality = SampleBufferMode

        customInfo.AppendLine(String.Format( _
        "Provider name: {0}", providerName))
        customInfo.AppendLine(String.Format( _
        "Buffering: {0}", buffer))
        customInfo.AppendLine(String.Format( _
        "Buffering modality: {0}", bufferModality))
    End Sub
   
   
   Public ReadOnly Property SampleUseBuffering() As Boolean
      Get
         Return UseBuffering
      End Get
    End Property

   
   Public ReadOnly Property SampleBufferMode() As String
      Get
         Return BufferMode
      End Get
    End Property

   ' Processes the incoming events.
    ' This method performs custom 
    ' processing and, if buffering is 
    ' enabled, it calls the base.ProcessEvent
    ' to buffer the event information.
    Public Overrides Sub ProcessEvent( _
    ByVal eventRaised As WebBaseEvent)

        If UseBuffering Then
            ' Buffering enabled, call the base event to
            ' buffer event information.
            MyBase.ProcessEvent(eventRaised)
        Else
            ' Buffering disabled, store the current event
            ' now.
            customInfo.AppendLine("*** Buffering disabled ***")
            customInfo.AppendLine(eventRaised.ToString())
            ' Store the information in the specified file.
            StoreToFile(customInfo, _
            logFilePath, FileMode.Append)
        End If
    End Sub
   

    Private Function GetEvents( _
    ByVal flushInfo As WebEventBufferFlushInfo) _
    As WebBaseEventCollection
        Return flushInfo.Events
    End Function 'GetEvents


    Private Function GetEventsDiscardedSinceLastNotification( _
    ByVal flushInfo _
    As WebEventBufferFlushInfo) As Integer
        Return flushInfo.EventsDiscardedSinceLastNotification
    End Function 'GetEventsDiscardedSinceLastNotification


    Private Function GetEventsInBuffer(ByVal flushInfo _
    As WebEventBufferFlushInfo) As Integer
        Return flushInfo.EventsInBuffer
    End Function 'GetEventsInBuffer


    Private Function GetLastNotificationTime(ByVal flushInfo _
    As WebEventBufferFlushInfo) As DateTime
        Return flushInfo.LastNotificationUtc
    End Function 'GetLastNotificationTime


    Private Function GetNotificationSequence(ByVal flushInfo _
    As WebEventBufferFlushInfo) As Integer
        Return flushInfo.NotificationSequence
    End Function 'GetNotificationSequence


    Private Function GetNotificationType(ByVal flushInfo _
    As WebEventBufferFlushInfo) _
    As EventNotificationType
        Return flushInfo.NotificationType
    End Function 'GetNotificationType


    ' Processes the messages that have been buffered.
    ' It is called by the ASP.NET when the flushing of 
    ' the buffer is required according to the parameters 
    ' defined in the <bufferModes> element of the 
    ' <healthMonitoring> configuration section.
    Public Overrides Sub ProcessEventFlush(ByVal flushInfo _
    As WebEventBufferFlushInfo)

        ' Customize event information to be sent to 
        ' the Windows Event Viewer Application Log.
        customInfo.AppendLine( _
        "SampleEventLogWebEventProvider buffer flush.")

        customInfo.AppendLine(String.Format( _
        "NotificationType: {0}", _
        GetNotificationType(flushInfo)))

        customInfo.AppendLine(String.Format( _
        "EventsInBuffer: {0}", _
        GetEventsInBuffer(flushInfo)))

        customInfo.AppendLine(String.Format( _
        "EventsDiscardedSinceLastNotification: {0}", _
GetEventsDiscardedSinceLastNotification( _
flushInfo)))

        ' Read each buffered event and send it to the
        ' Application Log.
        Dim eventRaised As WebBaseEvent
        For Each eventRaised In flushInfo.Events
            customInfo.AppendLine(eventRaised.ToString())
        Next eventRaised
        ' Store the information in the specified file.
        StoreToFile(customInfo, logFilePath, _
        FileMode.Append)
    End Sub

    ' Performs standard shutdown.
    Public Overrides Sub Shutdown()
        ' Here you need the code that performs
        ' those tasks required before shutting 
        ' down the provider.
        ' Flush the buffer, if needed.
        Flush()

    End Sub

    ' Store event information in a local file.
    Private Sub StoreToFile(ByVal [text] _
    As StringBuilder, ByVal filePath As String, _
    ByVal mode As FileMode)
        Dim writeBlock As Integer
        Dim startIndex As Integer

        Try

            writeBlock = 256
            startIndex = 0

            ' Open or create the local file 
            ' to store the event information.
            fs = New FileStream(filePath, mode, FileAccess.Write)

            ' Lock the file for writing.
            fs.Lock(startIndex, writeBlock)

            ' Create a stream writer
            Dim writer As New StreamWriter(fs)

            ' Set the file pointer to the current 
            ' position to keep adding data to it. 
            ' If you want to rewrite the file use 
            ' the following statement instead.
            ' writer.BaseStream.Seek (0, SeekOrigin.Begin);
            writer.BaseStream.Seek(0, SeekOrigin.Current)

            'If the file already exists it must not 
            ' be write protected otherwise  
            ' the following write operation 
            'fails silently.
            writer.Write([text].ToString())

            ' Update the underlying file
            writer.Flush()

            ' Unlock the file for other processes.
            fs.Unlock(startIndex, writeBlock)

            ' Close the stream writer and 
            'the underlying file     
            writer.Close()

            fs.Close()
        Catch e As Exception
            'Use this for debugging.
            'Never dispaly it!
            Dim ex As String = e.ToString()
            Throw New Exception( _
            "[SampleEventProvider] StoreToFile: exception.")
        End Try
    End Sub
End Class

以下設定檔摘錄展示了一個healthMonitoring設定區段，讓 ASP.NET 能使用上述定義的自訂提供者來處理所有健康監控事件。

<healthMonitoring
  heartBeatInterval="0" enabled="true">

  <bufferModes>
    <add name ="Custom Notification"
      maxBufferSize="10"
      maxFlushSize="5"
      urgentFlushThreshold="10"
      regularFlushInterval="Infinite"
      urgentFlushInterval="00:00:30"
      maxBufferThreads="1"
/>
  </bufferModes>

  <providers>
    <clear/>
    <add name="SampleBufferedWebEventProvider"
      type="SamplesAspNet.SampleBufferedWebEventProvider, bufferedwebeventprovider, Version=1.0.1785.14700, Culture=neutral, PublicKeyToken=d31491bf33b55954, processorArchitecture=MSIL"
      buffer="true"
      bufferMode="Custom Notification"
/>
  </providers>

  <profiles>
    <add name="Custom"
      minInstances="1"
      maxLimit="Infinite"
      minInterval="00:00:00" />
  </profiles>

  <rules>
    <clear />
      <add name="Custom Buffered Web Event Provider"
        eventName="All Events"
        provider="SampleBufferedWebEventProvider"
        profile="Custom" />
  </rules>

</healthMonitoring>

備註

ASP.NET 健康監控讓生產與營運人員能管理已部署的網頁應用程式。 System.Web.Management命名空間包含負責包裝應用程式健康狀態資料的健康事件類型，以及負責處理這些資料的提供者類型。 同時也包含協助健康事件管理的支援類型。

如果你想自訂健康事件處理，可以從類別 BufferedWebEventProvider 衍生出你自己的自訂緩衝提供者。

另請參閱

• WebEventBufferFlushInfo
• 安裝與配置 ASP.NET 供應商