Log4net in .net 6 webapi

Create a new web api project

dotnet new webapi

Add log4net

dotnet add package Microsoft.Extensions.Logging.Log4Net.AspNetCore

Add

builder.Logging.AddLog4Net();

call in your Program.cs file.

...
var builder = WebApplication.CreateBuilder(args);

// Add services to the container.

builder.Services.AddControllers();
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();
builder.Logging.AddLog4Net(); //here

var app = builder.Build();
...

The logging level by default is set to INFO. It can be found in appsettings.json and appsettings.{ENVIRONMENT}.json

Create a new file called log4net.config and this to the content

<?xml version="1.0" encoding="utf-8" ?>

<log4net>

    <root>

        <appender-ref ref="ConsoleAppender"/>

    </root>

    <appender name="ConsoleAppender" type="log4net.Appender.ConsoleAppender">

        <layout type="log4net.Layout.PatternLayout">

            <conversionPattern value="%d [%t] %-5p %logger - %m%n" />

        </layout>

    </appender>

</log4net>

Add some logging in a controller

public IEnumerable<WeatherForecast> Get()
{
    _logger.LogDebug("i am here");
    return Enumerable.Range(1, 5).Select(index => new WeatherForecast
    {
        Date = DateTime.Now.AddDays(index),
        TemperatureC = Random.Shared.Next(-20, 55),
        Summary = Summaries[Random.Shared.Next(Summaries.Length)]
    })
    .ToArray();
}

You will get this

2022-03-28 15:45:29,796 [.NET ThreadPool Worker] DEBUG log4netinwebapi.Controllers.WeatherForecastController - i am here