How to write to a custom event log?

Question

I'm trying to get my .Net Windows Service to right to a custom event log. I'm using EventLogInstaller to create the event log and source when the application is installed. I read here that it takes a while for Windows to register the source so they reccomend you restart the application before trying to write to the log.

As this is a Windows Service I didn't want to have to force a computer restart or get the user to manually start the service up, so I use this code to wait for the log to exist and then start the service automatically.

while (!(EventLog.Exists("ManageIT") || EventLog.SourceExists("ManageIT Client Service")))
{
    Thread.Sleep(1000);
}

System.ServiceProcess.ServiceController controller = new System.ServiceProcess.ServiceController("ManageIT.Client.Service");
controller.Start();

My problem is that events from the service are still written to the Application Log and although I can see my custom log in the Registry Editor it does not show up in the Windows 7 Event Viewer.

Any help will be much appreciated.

Solution 1

Try this snippet:

edit - caveat: if the user running the code does not have administrator rights, this will throw an exception. Since this is the case (and if the user will not have these rights) best practices should be to assume the log exists, and simply write to it. see: The source was not found, but some or all event logs could not be searched

if (!EventLog.SourceExists("MyApplicationEventLog"))
{
    EventSourceCreationData eventSourceData = new EventSourceCreationData("MyApplicationEventLog", "MyApplicationEventLog");
    EventLog.CreateEventSource(eventSourceData);
}

using (EventLog myLogger = new EventLog("MyApplicationEventLog", ".", "MyApplicationEventLog"))
{
    myLogger.WriteEntry("Error message", EventLogEntryType.Error);
    myLogger.WriteEntry("Info message", EventLogEntryType.Information);
}

Solution 2

By default when a service is installed, the source gets associated with the Application Log. If we change this association at a later point, the system needs a restart.

We can however prevent the association of the service with the application log, by setting autolog property to false in the service class (class which inherits from servicebase) constructor. http://msdn.microsoft.com/en-us/library/system.serviceprocess.servicebase.autolog.aspx

Solution 3

It sounds like you are writing to the event log like this:

 EventLog.WriteEntry("Source", "Message");

This will write to the application log.

If you use the code in simons post with the creation of myLogger, you can specify the name of the Log.