DELPHI access to U disk drive letter code

Delphi procedures used to achieve the U disk drive is not difficult to obtain, but for the new term may be a bit difficult to put out the code for them to learn from

 procedure TForm1.FormCreate (Sender: TObject);

 var

     buf: array [0 .. MAX_PATH-1] of char;

     m_Result: Integer;

     i: Integer;

     str_temp: string;

 begin

   m_Result: = GetLogicalDriveStrings (MAX_PATH, buf);

   for i: = 0 to (m_Result div 4) do

   begin

         str_temp: = string (buf [i * 4] + buf [i * 4 +1] + buf [i * 4 +2]);

          if getdrivetype (pchar (str_temp)) = DRIVE_REMOVABLE then

          begin

             showmessage (str_temp + 'set for U disk');

             ListBox1.Items.Add (str_temp);

         end;

   end;