LoggerColorBehavior usage

consoleapp.csproj

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net5.0</TargetFramework>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="5.0.0-rc.2.20475.5" />
    <PackageReference Include="Microsoft.Extensions.Logging.Console" Version="5.0.0-rc.2.20475.5" />
    <PackageReference Include="Microsoft.Extensions.Options" Version="5.0.0-rc.2.20475.5" />
  </ItemGroup>

</Project>

Program.cs

using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Logging.Abstractions;
using Microsoft.Extensions.Logging.Console;
using Microsoft.Extensions.Options;
using System;
using System.IO;
using System.Threading.Tasks;

namespace ConsoleApp77
{
    public static class ConsoleLoggerExtensions
    {
        public static ILoggingBuilder AddCustomFormatter(this ILoggingBuilder builder, Action<CustomOptions> configure)
        {
            return builder.AddConsole(o => { o.FormatterName = "customName"; })
                .AddConsoleFormatter<CustomFormatter, CustomOptions>(configure);
        }
    }

    public class CustomOptions : SimpleConsoleFormatterOptions
    {
        public string ArbitraryPrefixOnEachMessage { get; set; }
    }

    class Program
    {
        public static void Main(string[] args)
        {
            using var loggerFactory = LoggerFactory.Create(builder =>
            {
                builder
                //.AddSimpleConsole(x => x.ColorBehavior = LoggerColorBehavior.Disabled);
                .AddCustomFormatter(o =>
                {
                    o.ArbitraryPrefixOnEachMessage = "<padded prefix from formatter!> ";
                    o.ColorBehavior = LoggerColorBehavior.Enabled;
                });
            });

            var logger = loggerFactory.CreateLogger<Program>();
            logger.LogInformation("Random log \x1B[42mwith green background\x1B[49m message");
        }
    }

    public class CustomFormatter : ConsoleFormatter, IDisposable
    {
        private IDisposable _optionsReloadToken;

        public CustomFormatter(IOptionsMonitor<CustomOptions> options)
            // case insensitive name for the formatter
            : base("customName")
        {
            ReloadLoggerOptions(options.CurrentValue);
            _optionsReloadToken = options.OnChange(ReloadLoggerOptions);
        }

        private void ReloadLoggerOptions(CustomOptions options)
        {
            FormatterOptions = options;
        }

        public CustomOptions FormatterOptions { get; set; }
        public void Dispose()
        {
            _optionsReloadToken?.Dispose();
        }

        public override void Write<TState>(in LogEntry<TState> logEntry, IExternalScopeProvider scopeProvider, TextWriter textWriter)
        {
            string message = logEntry.Formatter(logEntry.State, logEntry.Exception);
            if (logEntry.Exception == null && message == null)
            {
                return;
            }
            if (DisableColors)
            {
                textWriter.Write(FormatterOptions.ArbitraryPrefixOnEachMessage);
            }
            else
            {
                textWriter.WriteWithColor(FormatterOptions.ArbitraryPrefixOnEachMessage, ConsoleColor.Black, ConsoleColor.Blue);
            }
            textWriter.WriteLine(message);
        }
        private bool DisableColors =>
          FormatterOptions.ColorBehavior == LoggerColorBehavior.Disabled ||
          (FormatterOptions.ColorBehavior == LoggerColorBehavior.Default && System.Console.IsOutputRedirected);
    }

    public static class TextWriterExtensions
    {
        public static void WriteWithColor(this TextWriter textWriter, string message, ConsoleColor? background, ConsoleColor? foreground)
        {
            // Order: backgroundcolor, foregroundcolor, Message, reset foregroundcolor, reset backgroundcolor
            if (background.HasValue)
            {
                textWriter.Write(GetBackgroundColorEscapeCode(background.Value));
            }
            if (foreground.HasValue)
            {
                textWriter.Write(GetForegroundColorEscapeCode(foreground.Value));
            }
            textWriter.Write(message);
            if (foreground.HasValue)
            {
                textWriter.Write(DefaultForegroundColor); // reset to default foreground color
            }
            if (background.HasValue)
            {
                textWriter.Write(DefaultBackgroundColor); // reset to the background color
            }
        }
        internal const string DefaultForegroundColor = "\x1B[39m\x1B[22m"; // reset to default foreground color
        internal const string DefaultBackgroundColor = "\x1B[49m"; // reset to the background color
        internal static string GetForegroundColorEscapeCode(ConsoleColor color)
        {
            return color switch
            {
                ConsoleColor.Black => "\x1B[30m",
                ConsoleColor.DarkRed => "\x1B[31m",
                ConsoleColor.DarkGreen => "\x1B[32m",
                ConsoleColor.DarkYellow => "\x1B[33m",
                ConsoleColor.DarkBlue => "\x1B[34m",
                ConsoleColor.DarkMagenta => "\x1B[35m",
                ConsoleColor.DarkCyan => "\x1B[36m",
                ConsoleColor.Gray => "\x1B[37m",
                ConsoleColor.Red => "\x1B[1m\x1B[31m",
                ConsoleColor.Green => "\x1B[1m\x1B[32m",
                ConsoleColor.Yellow => "\x1B[1m\x1B[33m",
                ConsoleColor.Blue => "\x1B[1m\x1B[34m",
                ConsoleColor.Magenta => "\x1B[1m\x1B[35m",
                ConsoleColor.Cyan => "\x1B[1m\x1B[36m",
                ConsoleColor.White => "\x1B[1m\x1B[37m",
                _ => DefaultForegroundColor // default foreground color
            };
        }

        internal static string GetBackgroundColorEscapeCode(ConsoleColor color)
        {
            return color switch
            {
                ConsoleColor.Black => "\x1B[40m",
                ConsoleColor.DarkRed => "\x1B[41m",
                ConsoleColor.DarkGreen => "\x1B[42m",
                ConsoleColor.DarkYellow => "\x1B[43m",
                ConsoleColor.DarkBlue => "\x1B[44m",
                ConsoleColor.DarkMagenta => "\x1B[45m",
                ConsoleColor.DarkCyan => "\x1B[46m",
                ConsoleColor.Gray => "\x1B[47m",
                _ => DefaultBackgroundColor // Use default background color
            };
        }
    }
}