The core logging package is Serilog. The supported platforms are .NET/.NET Core, .NET Framework 4.5+, Windows (8/WinRT/Universal+) and Windows Phone 8+.

$ dotnet add package Serilog
$ dotnet add package Serilog.Sinks.Console

Browse the Serilog tag on NuGet to see the available sinks, extensions and related third-party packages.

Types are in the Serilog namespace.

using Serilog;

The root Logger is created using LoggerConfiguration.

using var log = new LoggerConfiguration()
    .WriteTo.Console()
    .CreateLogger();

This is typically done once at application start-up, and the logger saved for later use by application classes. Multiple loggers can be created and used independently if required.

log.Information("Hello, Serilog!");

Serilog's global, statically accessible logger, is set via Log.Logger and can be invoked using the static methods on the Log class.

Log.Logger = log;
Log.Information("The global logger has been configured");

Configuring and using the Log class is an optional convenience that makes it easier for libraries to adopt Serilog. Serilog does not require any static/process-wide state within the logging pipeline itself, so using Logger/ILogger directly is fine.

The complete example below shows logging in a simple console application, with events sent to the console as well as a date-stamped rolling log file.

1. Create a new Console Application project

2. Install the core Serilog package, Console sink and File sink

At a shell prompt in the project directory, type:

$ dotnet add package Serilog
$ dotnet add package Serilog.Sinks.Console
$ dotnet add package Serilog.Sinks.File

3. Add the following code to Program.cs

using System;
using Serilog;

class Program
{
    static async Task Main()
    {
        Log.Logger = new LoggerConfiguration()
            .MinimumLevel.Debug()
            .WriteTo.Console()
            .WriteTo.File("logs/myapp.txt", rollingInterval: RollingInterval.Day)
            .CreateLogger();

        Log.Information("Hello, world!");

        int a = 10, b = 0;
        try
        {
            Log.Debug("Dividing {A} by {B}", a, b);
            Console.WriteLine(a / b);
        }
        catch (Exception ex)
        {
            Log.Error(ex, "Something went wrong");
        }
        finally
        {
            await Log.CloseAndFlushAsync();
        }
    }
}

4. Run the program