How to use Custom Logging in C#

// This snippet configures the logging mode for IronSoftware's Logger
// and assigns a custom logger implementation.

// Set the logger to use a custom logging mode by assigning it to Custom.
IronSoftware.Logger.LoggingMode = IronSoftware.Logger.LoggingModes.Custom;

// Initialize a custom logger and assign it to the CustomLogger property.
// Here, an instance of CustomLoggerClass is created with "logging" as an argument.
IronSoftware.Logger.CustomLogger = new CustomLoggerClass("logging");

// Note: The CustomLoggerClass should be implemented elsewhere in your codebase.
// It is expected to conform to the logging requirements specified by IronSoftware's Logger,
// meaning it should implement the necessary interface or methods to correctly handle logging operations.

' This snippet configures the logging mode for IronSoftware's Logger

' and assigns a custom logger implementation.



' Set the logger to use a custom logging mode by assigning it to Custom.

IronSoftware.Logger.LoggingMode = IronSoftware.Logger.LoggingModes.Custom



' Initialize a custom logger and assign it to the CustomLogger property.

' Here, an instance of CustomLoggerClass is created with "logging" as an argument.

IronSoftware.Logger.CustomLogger = New CustomLoggerClass("logging")



' Note: The CustomLoggerClass should be implemented elsewhere in your codebase.

' It is expected to conform to the logging requirements specified by IronSoftware's Logger,

' meaning it should implement the necessary interface or methods to correctly handle logging operations.

using System;
using Microsoft.Extensions.Logging;

// CustomLoggerClass implements the ILogger interface to provide a custom logging mechanism.
public class CustomLoggerClass : ILogger
{
    // Private field to store the category name associated with the logger instance.
    private readonly string categoryName;

    // Constructor initializes the logger with a category name, typically to identify the source or context of the log message.
    public CustomLoggerClass(string categoryName)
    {
        this.categoryName = categoryName;
    }

    // BeginScope allows for scoped logging, but in this implementation, it does not perform any action and returns null.
    // This can be expanded in the future if needed.
    public IDisposable BeginScope<TState>(TState state)
    {
        return null; // No scope management implemented yet.
    }

    // Checks if a given log level is enabled for this logger.
    // This implementation always returns true, meaning all log levels are enabled.
    public bool IsEnabled(LogLevel logLevel)
    {
        return true; // Logging is always enabled for all levels in this simple logger.
    }

    // Logs a message at the specified log level, with additional details provided by eventId, state, and exception.
    public void Log<TState>(LogLevel logLevel, EventId eventId, TState state, Exception exception, Func<TState, Exception, string> formatter)
    {
        if (formatter == null)
        {
            throw new ArgumentNullException(nameof(formatter)); // Throws exception if formatter is not provided.
        }

        // If the specified log level is not enabled, exit the method.
        if (!IsEnabled(logLevel))
        {
            return; // Short-circuiting if logging is not enabled.
        }

        // Use the formatter function to convert the state and exception into a log message.
        string logMessage = formatter(state, exception);

        // Write the composed log message to the console, including log level, category name, and the log message itself.
        Console.WriteLine($"[{DateTime.Now}] [{logLevel}] [{categoryName}] - {logMessage}");
    }
}

Imports System

Imports Microsoft.Extensions.Logging



' CustomLoggerClass implements the ILogger interface to provide a custom logging mechanism.

Public Class CustomLoggerClass

	Implements ILogger



	' Private field to store the category name associated with the logger instance.

	Private ReadOnly categoryName As String



	' Constructor initializes the logger with a category name, typically to identify the source or context of the log message.

	Public Sub New(ByVal categoryName As String)

		Me.categoryName = categoryName

	End Sub



	' BeginScope allows for scoped logging, but in this implementation, it does not perform any action and returns null.

	' This can be expanded in the future if needed.

	Public Function BeginScope(Of TState)(ByVal state As TState) As IDisposable

		Return Nothing ' No scope management implemented yet.

	End Function



	' Checks if a given log level is enabled for this logger.

	' This implementation always returns true, meaning all log levels are enabled.

	Public Function IsEnabled(ByVal logLevel As LogLevel) As Boolean

		Return True ' Logging is always enabled for all levels in this simple logger.

	End Function



	' Logs a message at the specified log level, with additional details provided by eventId, state, and exception.

	Public Sub Log(Of TState)(ByVal logLevel As LogLevel, ByVal eventId As EventId, ByVal state As TState, ByVal exception As Exception, ByVal formatter As Func(Of TState, Exception, String))

		If formatter Is Nothing Then

			Throw New ArgumentNullException(NameOf(formatter)) ' Throws exception if formatter is not provided.

		End If



		' If the specified log level is not enabled, exit the method.

		If Not IsEnabled(logLevel) Then

			Return ' Short-circuiting if logging is not enabled.

		End If



		' Use the formatter function to convert the state and exception into a log message.

		Dim logMessage As String = formatter(state, exception)



		' Write the composed log message to the console, including log level, category name, and the log message itself.

		Console.WriteLine($"[{DateTime.Now}] [{logLevel}] [{categoryName}] - {logMessage}")

	End Sub

End Class