Extended Logging Sample with .NET 4.5 Caller Info Attributes and NLog

CallerInfo.cs

using System;
using System.IO;
using System.Runtime.CompilerServices;
using NLog;

public sealed class CallerInfo
{
    private CallerInfo(string filePath, string memberName, int lineNumber)
    {
        this.FilePath = filePath;
        this.MemberName = memberName;
        this.LineNumber = lineNumber;
    }

    public static CallerInfo Create(
        [CallerFilePath] string filePath = "",
        [CallerMemberName] string memberName = "",
        [CallerLineNumber] int lineNumber = 0)
    {
        return new CallerInfo(filePath, memberName, lineNumber);
    }

    public string FilePath { get; private set; }

    public string FileName
    {
        get
        {
            return this.fileName ?? (this.fileName = Path.GetFileName(this.FilePath));
        }
    }

    public string MemberName { get; private set; }

    public int LineNumber { get; private set; }

    public override string ToString()
    {
        return string.Concat(this.FilePath, "|", this.MemberName, "|", this.LineNumber);
    }

    private string fileName;
}

public static class LoggerExtensions
{
    public static void TraceMemberEntry(
        this Logger logger,
        [CallerFilePath] string filePath = "",
        [CallerMemberName] string memberName = "",
        [CallerLineNumber] int lineNumber = 0)
    {
        LogMemberEntry(logger, LogLevel.Trace, filePath, memberName, lineNumber);
    }

    public static void TraceMemberExit(
        this Logger logger,
        [CallerFilePath] string filePath = "",
        [CallerMemberName] string memberName = "",
        [CallerLineNumber] int lineNumber = 0)
    {
        LogMemberExit(logger, LogLevel.Trace, filePath, memberName, lineNumber);
    }

    public static void DebugMemberEntry(
        this Logger logger,
        [CallerFilePath] string filePath = "",
        [CallerMemberName] string memberName = "",
        [CallerLineNumber] int lineNumber = 0)
    {
        LogMemberEntry(logger, LogLevel.Debug, filePath, memberName, lineNumber);
    }

    public static void DebugMemberExit(
        this Logger logger,
        [CallerFilePath] string filePath = "",
        [CallerMemberName] string memberName = "",
        [CallerLineNumber] int lineNumber = 0)
    {
        LogMemberExit(logger, LogLevel.Debug, filePath, memberName, lineNumber);
    }

    public static void LogMemberEntry(
        this Logger logger,
        LogLevel logLevel,
        [CallerFilePath] string filePath = "",
        [CallerMemberName] string memberName = "",
        [CallerLineNumber] int lineNumber = 0)
    {
        const string MsgFormat = "Entering member {1} at line {2}";

        InternalLog(logger, logLevel, MsgFormat, filePath, memberName, lineNumber);
    }

    public static void LogMemberExit(
        this Logger logger,
        LogLevel logLevel,
        [CallerFilePath] string filePath = "",
        [CallerMemberName] string memberName = "",
        [CallerLineNumber] int lineNumber = 0)
    {
        const string MsgFormat = "Exiting member {1} at line {2}";

        InternalLog(logger, logLevel, MsgFormat, filePath, memberName, lineNumber);
    }

    private static void InternalLog(
        Logger logger,
        LogLevel logLevel,
        string format,
        string filePath,
        string memberName,
        int lineNumber)
    {
        if (logger == null)
            throw new ArgumentNullException("logger");

        if (logLevel == null)
            throw new ArgumentNullException("logLevel");

        logger.Log(logLevel, format, filePath, memberName, lineNumber);
    }
}