public static string MakeRelativePath(string absoluteFilePath, string baseDirectory)
        {
            if (null == absoluteFilePath)
                throw new ArgumentNullException(nameof(absoluteFilePath));

            if (null == baseDirectory)
                throw new ArgumentNullException(nameof(baseDirectory));

            //absoluteFilePath = Path.GetFullPath(absoluteFilePath);
            //baseDirectory = Path.GetFullPath(baseDirectory);

            var directorySeparator = Path.DirectorySeparatorChar.ToString(CultureInfo.InvariantCulture);
            var altDirectorySeparator = Path.AltDirectorySeparatorChar.ToString(CultureInfo.InvariantCulture);

            string[] separators =
            {
                directorySeparator,
                altDirectorySeparator
            };

            string[] absoluteFilePathParts = absoluteFilePath.Split(separators, StringSplitOptions.RemoveEmptyEntries);
            string[] baseDirectoryParts = baseDirectory.Split(separators, StringSplitOptions.RemoveEmptyEntries);

            int length = Math.Min(absoluteFilePathParts.Length, baseDirectoryParts.Length);

            int offset = 0;

            for (int i = 0; i < length; i++)
            {
                if (absoluteFilePathParts[i].Equals(baseDirectoryParts[i], StringComparison.Ordinal))
                    offset++;
                else break;
            }

            if (0 == offset)
            {
                if (!absoluteFilePath.StartsWith(directorySeparator)) // Linux
                    throw new ArgumentException("Paths do not have a common base!");
            }

            var relativePath = new StringBuilder();

            for (int i = 0; i < baseDirectoryParts.Length - offset; i++)
            {
                relativePath.Append("..");
                relativePath.Append(Path.DirectorySeparatorChar);
            }

            for (int i = offset; i < absoluteFilePathParts.Length - 1; i++)
            {
                relativePath.Append(absoluteFilePathParts[i]);
                relativePath.Append(Path.DirectorySeparatorChar);
            }

            relativePath.Append(absoluteFilePathParts[absoluteFilePathParts.Length - 1]);

            return relativePath.ToString();
        }