Custom AppenderSkeleton

ServiceTest.cs

        public class CustomMemoryAppender : AppenderSkeleton
        {
            private readonly StringBuilder logBuffer;
            readonly StringWriter stringWriter;
            private readonly object lockObject = new object();

            public CustomMemoryAppender()
            {
                logBuffer = new StringBuilder();
                stringWriter = new StringWriter(logBuffer);

            }

            protected override void Append(LoggingEvent loggingEvent)
            {
                lock (lockObject)
                {
                    if (Layout == null)
                    {
                        logBuffer.AppendLine(string.Format("{0} - {1}", loggingEvent.Level, loggingEvent.RenderedMessage));
                    }
                    else
                    {
                        Layout.Format(stringWriter, loggingEvent);
                    }
                }
            }

            public string ReadBuffer()
            {
                lock (lockObject)
                {
                    string retVal = logBuffer.ToString();
                    logBuffer.Clear();
                    return retVal;
                }
            }
        }