EntryWritten Event
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EventLog.EntryWritten Event


Occurs when an entry is written to an event log on the local computer.

Namespace:   System.Diagnostics
Assembly:  System (in System.dll)

Public Event EntryWritten As EntryWrittenEventHandler

To get event notifications, you must set EnableRaisingEvents to true. You can only receive event notifications when entries are written on the local computer. You cannot receive notifications for entries written on remote computers.

When you create an EntryWritten delegate, you identify the method that will handle the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, until you remove the delegate. For more information about handling events with delegates, see Handling and Raising Events.

The system responds to WriteEntry only if the last write event occurred at least six seconds previously. This implies you will only receive one EntryWritten event notification within a six-second interval, even if more than one event log change occurs. If you insert a sufficiently long sleep interval (around 10 seconds) between calls to WriteEntry, you are less likely to miss an event. However, if write events occur more frequently, you might not recieve the event notification until the next interval. Typically, missed event notifications are not lost, but delayed.

The following example handles an entry written event.

Option Explicit On 
Option Strict On

Imports System
Imports System.Diagnostics
Imports System.Threading

Class MySample

    ' This member is used to wait for events.
    Private Shared signal As AutoResetEvent

    Public Shared Sub Main()

        signal = New AutoResetEvent(False)
        Dim myNewLog As New EventLog("Application", ".", "testEventLogEvent")

        AddHandler myNewLog.EntryWritten, AddressOf MyOnEntryWritten
        myNewLog.EnableRaisingEvents = True
        myNewLog.WriteEntry("Test message", EventLogEntryType.Information)

    End Sub ' Main

    Public Shared Sub MyOnEntryWritten(ByVal [source] As Object, ByVal e As EntryWrittenEventArgs)
        Console.WriteLine("In event handler")
    End Sub ' MyOnEntryWritten
End Class ' MySample 


for administering event log information on the computer. Associated enumeration: EventLogPermissionAccess.Administer

.NET Framework
Available since 1.1
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