private FileStream GetFileStream(String eventSource)
{
if (DirectoryName.IsNullOrWhiteSpace())
{
DirectoryName = DefaultDirectory;
}
var fileInfo = new FileInfo(Path.Combine(DirectoryName, DateTime.Now.ToString(DateTimeFormat), eventSource + ".log"));
Directory.CreateDirectory(fileInfo.DirectoryName);
return(FileStreams.GetOrAdd(fileInfo.FullName, filePath => new FileStream(filePath, FileMode.Append, FileAccess.Write, FileShare.ReadWrite)));
}
