NLog.Targets.FileTarget.ArchiveByDate C# (CSharp) Method

        private void ArchiveByDate(string fileName, string pattern, LogEventInfo logEvent)
        {
            string dirName = Path.GetDirectoryName(Path.GetFullPath(pattern));
            if (dirName != null)
            {
                DateTime archiveDate = GetArchiveDate(fileName, logEvent);
                string fileNameMask = ReplaceFileNamePattern(pattern, "*");
                string dateFormat = GetArchiveDateFormatString(this.ArchiveDateFormat);
                string archiveFileName = Path.Combine(dirName, fileNameMask.Replace("*", archiveDate.ToString(dateFormat)));
                ArchiveFile(fileName, archiveFileName);
            }

            DeleteOldDateArchives(pattern);
        }