C#でログ機能を実装してみた

class Log
{
	protected static Log _instance;
	protected Log() {}

	public Log GetCurrentLogger()
	{
		if (null == Log._instance) {
			Log,_instance = new Log();
		}
		return _instance;
	}

	public delegate void LogEventHandler(object sender, EventArgs e);

	public event LogEventHandler debugEventHandler;
	void DEBUG(string message)
	{
		var eventArg = new LogEventHandler(message);
		debugEventHandler?.Invoke(this, eventArg);
	}
}

class CommonBaseObject
{
	public void DEBUG(string message)
	{
		var logger = Log.GetCurrentLogger()
		logger.DEBUG(message);
	}
}

public class Program
{
	static void SetupLogger(ref ILogEvent logEvent)
	{
		var logger = Log.GetInstance();
		logger.TraceLogEventHandler += logEvent.TRACE;
		logger.DebugLogEventHandler += logEvent.DEBUG;
		logger.InfoLogEventHandler += logEvent.INFO;
		logger.WarnLogEventHandler += logEvent.WARN;
		logger.ErrorLogEventHandler += logEvent.ERROR;
		logger.FatalLogEventHandler += logEvent.FATAL;
	}

	static void Main(string[] args)
	{
		ILogEvent consoleLog = new CSEngineer.Logger.Console.Log();
		ILogEvent fileLog = new CSEngineer.Logger.File.Log();

		SetupLogger(ref consoleLog);
		SetupLogger(ref fileLog);

		var sampleClass = new LoggerSampleClass();
		sampleClass.Sample();

		return;
	}
}

public class LoggerSampleClass : CommonBaseObject
{
	public LoggerSampleClass() { }

	public void Sample()
	{
		base.TRACE("Sample TRACE message");
		base.DEBUG("Sample DEBUG message");
		base.INFO("Sample INFO message");
		base.WARN("Sample WARN message");
		base.ERROR("Sample ERROR message");
		base.FATAL("Sample FATAL message");
	}
}

public class CommonBaseObject : ILogger
{
	public void DEBUG(string message)
	{
		var logger = Log.GetInstance();
		logger.DEBUG(message);
	}

	public void ERROR(string message)
	{
		var logger = Log.GetInstance();
		logger.ERROR(message);
	}

	public void FATAL(string message)
	{
		var logger = Log.GetInstance();
		logger.FATAL(message);
	}

	public void INFO(string message)
	{
		var logger = Log.GetInstance();
		logger.INFO(message);
	}

	public void TRACE(string message)
	{
		var logger = Log.GetInstance();
		logger.TRACE(message);
	}

	public void WARN(string message)
	{
		var logger = Log.GetInstance();
		logger.WARN(message);
	}
}

interface ILogger
{
	void TRACE(string message);
	void DEBUG(string message);
	void INFO(string message);
	void WARN(string message);
	void ERROR(string message);
	void FATAL(string message);
}