object.Type 

function ShowFileType(filespec)
{
   var fso, f, s;
   fso = new ActiveXObject("Scripting.FileSystemObject");
   if (fso.FolderExists(filespec))
      f = fso.GetFolder(filespec);
   else if (fso.FileExists(filespec))
      f = fso.GetFile(filespec);
   else
      s = "File or Folder does not exist.";
   s = f.Name + " is a " + f.Type; 
   return(s);
}

Function ShowFolderType(filespec)
   Dim fso, f, s
   Set fso = CreateObject("Scripting.FileSystemObject")
   Set f = fso.GetFolder(filespec)
   s = UCase(f.Name) & " is a " & f.Type
   ShowFolderType = s
End Function