public override void ActivateOptions()

in src/log4net/Appender/EventLogAppender.cs [222:286]
51 lines of code
9 McCabe index (conditional complexity)

  public override void ActivateOptions()
  {
    try
    {
      base.ActivateOptions();

      SecurityContext ??= SecurityContextProvider.DefaultProvider.CreateSecurityContext(this);

      bool sourceAlreadyExists;
      string? currentLogName = null;

      using (SecurityContext.Impersonate(this))
      {
        sourceAlreadyExists = EventLog.SourceExists(ApplicationName);
        if (sourceAlreadyExists)
        {
          currentLogName = EventLog.LogNameFromSourceName(ApplicationName, MachineName);
        }
      }

      if (sourceAlreadyExists && currentLogName != LogName)
      {
        LogLog.Debug(_declaringType, $"Changing event source [{ApplicationName}] from log [{currentLogName}] to log [{LogName}]");
      }
      else if (!sourceAlreadyExists)
      {
        LogLog.Debug(_declaringType, $"Creating event source Source [{ApplicationName}] in log {LogName}]");
      }

      string? registeredLogName = null;

      using (SecurityContext.Impersonate(this))
      {
        if (sourceAlreadyExists && currentLogName != LogName)
        {
          //
          // Re-register this to the current application if the user has changed
          // the application / logfile association
          //
          EventLog.DeleteEventSource(ApplicationName, MachineName);
          CreateEventSource(ApplicationName, LogName, MachineName);

          registeredLogName = EventLog.LogNameFromSourceName(ApplicationName, MachineName);
        }
        else if (!sourceAlreadyExists)
        {
          CreateEventSource(ApplicationName, LogName, MachineName);

          registeredLogName = EventLog.LogNameFromSourceName(ApplicationName, MachineName);
        }
      }

      _levelMapping.ActivateOptions();

      LogLog.Debug(_declaringType, $"Source [{ApplicationName}] is registered to log [{registeredLogName}]");
    }
    catch (System.Security.SecurityException ex)
    {
      ErrorHandler.Error($"Caught a SecurityException trying to access the EventLog.  Most likely the event source {ApplicationName}"
          + " doesn't exist and must be created by a local administrator.  Will disable EventLogAppender."
          + "  See http://logging.apache.org/log4net/release/faq.html#trouble-EventLog",
          ex);
      Threshold = Level.Off;
    }
  }