WebEventProvider 類別

定義

提供無緩衝事件提供者的基底類別。

public ref class WebEventProvider abstract : System::Configuration::Provider::ProviderBase
public abstract class WebEventProvider : System.Configuration.Provider.ProviderBase
type WebEventProvider = class
    inherit ProviderBase
Public MustInherit Class WebEventProvider
Inherits ProviderBase
繼承
WebEventProvider
衍生

範例

下列程式碼範例示範如何衍生自 WebEventProvider 類別,以建立自訂提供者,以將設定的事件寫入必須授與適當存取權限的本機檔案。 這個自訂提供者範例很簡單,其主要目的是要讓您完全控制其基本機制。 在真實世界案例中,您可以使用此提供者,特別是範例 BufferedWebEventProvider 緩衝提供者,作為應用程式行為的初步探查。 這可協助您在設計階段瞭解可用的資訊;然後,您可以稍後將此資訊導向更複雜的提供者。

下列組態檔摘錄顯示區 healthMonitoring 段組態,可讓 ASP.NET 使用上述定義的自訂提供者來處理所有健康情況監視事件。

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

    <providers>  

      <add name="SampleWebEventProvider"   
        type="SamplesAspNet.SampleEventProvider,webeventprovider, Version=1.0.1773.33989, Culture=neutral, PublicKeyToken=cf85aa6c978d9dea, processorArchitecture=MSIL" />  

    </providers>  

    <rules>  

      <rule   
        name="Custom Event Provider"  
        eventName="All Events"  
        provider="SampleWebEventProvider"  
        profile="Default" />  
    </rules>  

</healthMonitoring>  

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

namespace SamplesAspNet
{
  // Implements a custom event provider.
    public class SampleEventProvider : 
        System.Web.Management.WebEventProvider
    {

        // The local path of the file where
        // to store event information.
        private string logFilePath;
    
        // The current number of buffered messages 
        private int msgCounter;

        // The max number of messages to buffere.
        private int maxMsgNumber;

        // The message buffer.
        private System.Collections.Generic.Queue
            <WebBaseEvent> msgBuffer = 
            new Queue<WebBaseEvent>();

        // Initializes the provider.
        public SampleEventProvider(): base()
        {

            // Initialize the local path of the file 
            // that holds event information.
            logFilePath = "C:/test/log.doc";

            // Clear the message buffer.
            msgBuffer.Clear();

            // Initialize the max number of messages
            // to buffer.
            maxMsgNumber = 10;

            // More custom initialization goes here.
        }

        // Flush the input buffer if required.
        public override void Flush()
        {
            // Create a string builder to 
            // hold the event information.
            StringBuilder reData = new StringBuilder();

            // Store custom information.
            reData.Append("SampleEventProvider processing." +
                Environment.NewLine);
            reData.Append("Flush done at: {0}" +
                DateTime.Now.TimeOfDay.ToString() +
                Environment.NewLine);
            
            foreach (WebBaseEvent e in msgBuffer)
            {
                // Store event data.
                reData.Append(e.ToString());
            }

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

            // Reset the message counter.
            msgCounter = 0;
            
            // Clear the buffer.
            msgBuffer.Clear();
        }


        // Shutdown the provider.
        public override void Shutdown()
        {
            Flush();
        }


        // Process the event that has been raised.
        public override void ProcessEvent(WebBaseEvent raisedEvent)
        { 
            if (msgCounter < maxMsgNumber)
            {
                // Buffer the event information.
                msgBuffer.Enqueue(raisedEvent);
                // Increment the message counter.
                msgCounter += 1;
            }
            else
            {
                // Flush the buffer.
                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.
                FileStream 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)
            {
                throw new Exception(
                    "SampleEventProvider.StoreToFile: " 
                    + e.ToString());
            }
        }
    }
}
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 SampleEventProvider
    Inherits System.Web.Management.WebEventProvider
    
    ' The local path of the file where
    ' to store event information.
    Private logFilePath As String
    
    ' The current number of buffered messages 
    Private msgCounter As Integer
    
    ' The max number of messages to buffere.
    Private maxMsgNumber As Integer
    
    ' The message buffer.
    '  private System.Collections.Generic.Queue
    Private msgBuffer _
    As System.Collections.Generic.Queue( _
    Of System.Web.Management.WebBaseEvent) = _
    New System.Collections.Generic.Queue( _
    Of System.Web.Management.WebBaseEvent)


    ' Initializes the provider.
    Public Sub New() 
        
        ' Initialize the local path of the file 
        ' that holds event information.
        logFilePath = "C:/test/log.doc"
        
        ' Clear the message buffer.
        msgBuffer.Clear()
        
        ' Initialize the max number of messages
        ' to buffer.
        maxMsgNumber = 10
    
    End Sub
     
    ' More custom initialization goes here.
    
    ' Flush the input buffer if required.
    Public Overrides Sub Flush() 
        ' Create a string builder to 
        ' hold the event information.
        Dim reData As New StringBuilder()
        
        ' Store custom information.
        reData.Append( _
        "SampleEventProvider processing." + _
        Environment.NewLine)

        reData.Append( _
        "Flush done at: {0}" + _
        DateTime.Now.TimeOfDay.ToString() + _
        Environment.NewLine)
        
        Dim e As WebBaseEvent
        For Each e In  msgBuffer
            ' Store event data.
            reData.Append(e.ToString())
        Next e
        
        ' Store the information in the specified file.
        StoreToFile(reData, logFilePath, FileMode.Append)
        
        ' Reset the message counter.
        msgCounter = 0
        
        ' Clear the buffer.
        msgBuffer.Clear()
    
    End Sub
     
    ' Shutdown the provider.
    Public Overrides Sub Shutdown() 
        Flush()
    
    End Sub
    
    ' Process the event that has been raised.
    Public Overrides Sub ProcessEvent( _
    ByVal raisedEvent As WebBaseEvent)

        If msgCounter < maxMsgNumber Then
            ' Buffer the event information.
            msgBuffer.Enqueue(raisedEvent)
            ' Increment the message counter.
            msgCounter += 1
        Else
            ' Flush the buffer.
            Flush()
        End If

    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.
            Dim fs As 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
            Throw New Exception( _
            "SampleEventProvider.StoreToFile: " + _
            e.ToString())
        End Try

    End Sub
End Class

備註

ASP.NET 健康情況監視可讓生產與作業人員管理已部署的 Web 應用程式。 System.Web.Management命名空間包含負責封裝應用程式健康狀態資料的健全狀況事件種類,以及負責處理此資料的提供者類型。 它也包含支援類型,可協助管理健康情況事件。

如果您想要自訂健康情況事件處理,您可以從 類別衍生 WebEventProvider 來建立您自己的自訂提供者。

注意

在大部分情況下,您將能夠使用實作的 ASP.NET 健康情況監視類型,而且您會在組態區段中指定值 healthMonitoring 來控制健康情況監視系統。 您也可以衍生自健康情況監視類型,以建立您自己的自訂事件和提供者。 如需衍生自 類別的 WebEventProvider 範例,請參閱本主題中提供的範例。

建構函式

WebEventProvider()

初始化 WebEventProvider 類別的新執行個體。

屬性

Description

取得簡短、易讀的描述,適合顯示在管理工具或其他使用者介面 (UI) 中。

(繼承來源 ProviderBase)
Name

取得用來在設定期間代表提供者的易記名稱。

(繼承來源 ProviderBase)

方法

Equals(Object)

判斷指定的物件是否等於目前的物件。

(繼承來源 Object)
Flush()

將事件從提供者的緩衝區移至事件記錄檔。

GetHashCode()

做為預設雜湊函式。

(繼承來源 Object)
GetType()

取得目前執行個體的 Type

(繼承來源 Object)
Initialize(String, NameValueCollection)

初始化設定產生器。

(繼承來源 ProviderBase)
MemberwiseClone()

建立目前 Object 的淺層複製。

(繼承來源 Object)
ProcessEvent(WebBaseEvent)

處理傳遞給提供者的事件。

Shutdown()

執行與關閉提供者關聯的工作。

ToString()

傳回代表目前物件的字串。

(繼承來源 Object)

適用於

另請參閱