FilePath.cs

public class FilePath
{
    public FilePath(string fullPath)
    {
        FullPath = fullPath;
    }

    public string FullPath { get; }

    public string FileName => Path.GetFileName(FullPath);
    public string FileNameWithOutExtension => Path.GetFileNameWithoutExtension(FullPath);
    public string Extension => Path.GetExtension(FullPath);

    public override string ToString()
    {
        if (FullPath.Length <= 11) return FullPath;

        if (FullPath.Length == 0) return "";

        var fileName = Path.GetFileName(FullPath);

        return @$"...\{fileName}";
    }
}