didourebai / crosslayer

This project will show you how you can use the Log4Net and Logger inside a Console App in Framework 2.1 RC1, it can be used even in a Web App

Project Status To use this DLL you can refer to the sample as a Console App, this can be used in a Web App. var logRepository = LogManager.GetRepository(Assembly.GetEntryAssembly());

        XmlConfigurator.Configure(logRepository, new FileInfo("App.config"));

        var logger = LogManager.GetLogger(typeof(Program));

        logger.Error("Hello World!");

If we want to use this in an ASP.NET Core 2.0, a web application, we need to add a log provider(LoggerProvider) that is an extension using ILoggerProvider. This is an example:

public LoggerProvider : ILoggerProvider {   private readonly string _log4NetConfigFile;   private readonly ConcurrentDictionary<string, Logger> _loggers = new ConcurrentDictionary<string, Logger>();   public Log4NetProvider(string log4NetConfigFile) { _log4NetConfigFile = log4NetConfigFile; } public ILogger CreateLogger(string categoryName) { return _loggers.GetOrAdd(categoryName, CreateLoggerImplementation); }

public void Dispose()
{
    _loggers.Clear();
}
private Log4NetLogger CreateLoggerImplementation(string name)
{
    return new Log4NetLogger(name, Parselog4NetConfigFile(_log4NetConfigFile));
}

private static XmlElement Parselog4NetConfigFile(string filename)
{
    XmlDocument log4netConfig = new XmlDocument();
    log4netConfig.Load(File.OpenRead(filename));
    return log4netConfig["log4net"];
}   

Finally we will add the extension of the LoggerFactory:

public static class Log4netExtensions { public static ILoggerFactory AddLog4Net(this ILoggerFactory factory, string log4NetConfigFile) { factory.AddProvider(new Log4NetProvider(log4NetConfigFile)); return factory; }

public static ILoggerFactory AddLog4Net(this ILoggerFactory factory)
{
    factory.AddProvider(new Log4NetProvider("log4net.config"));
    return factory;
}

And now, we can use it il our web application in this way:

public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory) { loggerFactory.AddLog4Net();

        if (env.IsDevelopment())
        {
            app.UseDeveloperExceptionPage();
        }
        app.UseMvcWithDefaultRoute();
    }