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Interface for custom log handler implementation.

ILogHandler interface to ease unit-testing and mocking of loggers.

#pragma strict
public class MyFileLogHandler implements ILogHandler {
	private var m_FileStream: FileStream;
	private var m_StreamWriter: StreamWriter;
	private var m_DefaultLogHandler: ILogHandler = Debug.logger.logHandler;
	MyFileLogHandler {
		var filePath: String = Application.persistentDataPath + "/MyLogs.txt";
		m_FileStream = new FileStream(filePath, FileMode.OpenOrCreate, FileAccess.ReadWrite);
		m_StreamWriter = new StreamWriter(m_FileStream);
		// Replace the default debug log handler
		Debug.logger.logHandler = this;
	public function LogFormat(logType: LogType, context: UnityEngine.Object, format: String, args: Object[]) {
		m_StreamWriter.WriteLine(String.Format(format, args));
		m_DefaultLogHandler.LogFormat(logType, context, format, args);
	public function LogException(exception: Exception, context: UnityEngine.Object) {
		m_DefaultLogHandler.LogException(exception, context);
public class MyGameClass extends MonoBehaviour {
	private static var logger: ILogger = Debug.logger;
	private static var kTAG: String = "MyGameTag";
	private var myFileLogHandler: MyFileLogHandler;
	function Start() {
		myFileLogHandler = new MyFileLogHandler();
		logger.Log(kTAG, "MyGameClass Start.");
using UnityEngine;
using System.Collections;
using System.IO;
using System;

public class MyFileLogHandler : ILogHandler { private FileStream m_FileStream; private StreamWriter m_StreamWriter; private ILogHandler m_DefaultLogHandler = Debug.logger.logHandler;

public MyFileLogHandler() { string filePath = Application.persistentDataPath + "/MyLogs.txt";

m_FileStream = new FileStream (filePath, FileMode.OpenOrCreate, FileAccess.ReadWrite); m_StreamWriter = new StreamWriter (m_FileStream);

// Replace the default debug log handler Debug.logger.logHandler = this; }

public void LogFormat (LogType logType, UnityEngine.Object context, string format, params object[] args) { m_StreamWriter.WriteLine ( String.Format (format, args) ); m_StreamWriter.Flush (); m_DefaultLogHandler.LogFormat (logType, context, format, args); }

public void LogException (Exception exception, UnityEngine.Object context) { m_DefaultLogHandler.LogException (exception, context); } }

public class MyGameClass : MonoBehaviour { private static ILogger logger = Debug.logger; private static string kTAG = "MyGameTag"; private MyFileLogHandler myFileLogHandler;

void Start() { myFileLogHandler = new MyFileLogHandler();

logger.Log(kTAG, "MyGameClass Start."); } }

Public Functions

LogExceptionA variant of ILogHandler.LogFormat that logs an exception message.
LogFormatLogs a formatted message.