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WebApplicationLifetimeEvent Class

Represents a significant event in the lifetime of an application.

Namespace:  System.Web.Management
Assembly:  System.Web (in System.Web.dll)

[AspNetHostingPermissionAttribute(SecurityAction.LinkDemand, Level = AspNetHostingPermissionLevel.Minimal)]
[AspNetHostingPermissionAttribute(SecurityAction.InheritanceDemand, Level = AspNetHostingPermissionLevel.Minimal)]
public class WebApplicationLifetimeEvent : WebManagementEvent

ASP.NET health monitoring allows production and operations staff to manage deployed Web applications. The System.Web.Management namespace contains the health-event types responsible for packaging application health-status data and the provider types responsible for processing this data. It also contains supporting types that help during the management of health events.

Application lifetime events include events such as application startup and shutdown events. If an application is terminated, you can determine why by viewing the related event message field.

When a WebApplicationLifetimeEvent instance occurs, ASP.NET health monitoring updates the Application Lifetime Events performance counter. You can log these events by adding the WebApplicationLifetimeEvent object to the rules subsection of the healthMonitoring section of the configuration file, as shown in the following example.

  <add name="Application Events"
    eventName="Application Lifetime Events"
    minInterval="00:01:00" />

The Application Lifetime Events performance counter contains the sum total of all ASP.NET lifetime events. To view this performance counter in System Monitor (PerfMon), in the Add Counters window select ASP.NET from the Performance object drop-down list. Select the Application Lifetime Events performance counter, and click the Add button. For more information, see "Using the System Monitor (PerfMon) with ASP.NET Applications" on MSDN. If you allow events to be logged by the standard EventLogWebEventProvider, you can view them in Event Viewer by selecting the Application log. For more information, see Event Viewer in the Windows Server 2003 documentation on TechNet.

Caution noteCaution:

Because the WebApplicationLifetimeEvent object is a high-volume event, logging it is resource-intensive and might slow down your system. It can also cause other events to be overwritten in the case of the EventLogWebEventProvider class due to the high volume of events and the way the event logging works.


In most cases you will be able to use the ASP.NET health-monitoring types as implemented, and you will control the health-monitoring system by specifying values in the healthMonitoring configuration section. You can also derive from the health-monitoring types to create your own custom events and providers. For an example of deriving from the WebApplicationLifetimeEvent class, see the example provided in this topic.

Notes to Inheritors:

When formatting your custom event information for display, override the FormatCustomEventDetails method rather than the ToString method. This will avoid overwriting or tampering with sensitive system information.

The following code example shows how to derive from the WebApplicationLifetimeEvent class to create a custom event.

using System;
using System.Text;
using System.Web;
using System.Web.Management;

namespace SamplesAspNet
  // Implements a custom WebManagementEvent class.  
    public class SampleWebApplicationLifetimeEvent :
        private string customCreatedMsg, customRaisedMsg;

        // Invoked in case of events identified only by  
        // their event code. 
        public SampleWebApplicationLifetimeEvent(string msg, 
            object eventSource, int eventCode):
          base(msg, eventSource, eventCode)
            // Perform custom initialization.
            customCreatedMsg =
            string.Format("Event created at: {0}",

        // Invoked in case of events identified by their  
        // event code.and related event detailed code. 
        public SampleWebApplicationLifetimeEvent(string msg, 
            object eventSource, int eventCode, 
            int eventDetailCode):
          base(msg, eventSource, eventCode, eventDetailCode)
            // Perform custom initialization.
            customCreatedMsg =
             string.Format("Event created at: {0}",

        // Raises the SampleWebRequestEvent. 
        public override void Raise()
            // Perform custom processing. 
            customRaisedMsg = string.Format(
                "Event raised at: {0}\n", 
            // Raise the event. 

        //Formats Web request event information. 
        public override void FormatCustomEventDetails(
            WebEventFormatter formatter)

            // Add custom data.

            formatter.IndentationLevel += 1;

            formatter.TabSize = 4;

                 "*SampleWebApplicationLifetimeEvent Start *");
            formatter.AppendLine("Custom information goes here");
                "* SampleWebApplicationLifetimeEvent End *");
            // Display custom event timing.

            formatter.IndentationLevel -= 1;



The following configuration-file excerpt shows how to configure the healthMonitoring section of a configuration file to add the SampleWebApplicationLifetimeEvent code defined above to the ASP.NET health-monitoring system. To add the event to the system, you must define the event by adding a new entry to the eventMappings section and map the event to a provider by adding a new entry to the rules section.


       <clear />
       <!-- Configure the application lifetime event -->
       <!-- object to handle the Web application events. -->
       <add name="SampleApplicationLifetimeEvents"
         Culture=neutral,PublicKeyToken=b03f5f7f11d50a3a" />

       // Configure the connection between the 
       // application lifetime event object 
       // and the provider that must process it.
       <add name="Custom Application Events"
         minInterval="00:01:00" />



Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0