public static string MimeType(this FileSystemInfoEx info) { if (info is DirectoryInfoEx) { return("Folder"); } else if (info is FileInfoEx finfo) { if (info.IsSymLink()) { return("Shortcut"); } var ext = finfo.Extension; Microsoft.Win32.RegistryKey regKey = Microsoft.Win32.Registry.ClassesRoot.OpenSubKey(ext); if (regKey != null && regKey.GetValue("Content Type") != null) { return(regKey.GetValue("Content Type").ToString()); } return(info.Extension); } return(string.Empty); }