procedure DeleteDir1();
var
 DirInfo: TSearchRec;
 r: integer;
begin
 r := FindFirst('C:\Download\*.*', FaAnyfile, DirInfo);
 while r = 0 do begin
   if ((DirInfo.Attr and FaDirectory <> FaDirectory) and
      (DirInfo.Attr and FaVolumeId <> FaVolumeID))
   then
     if not DeleteFile(pChar('C:\Download\' + DirInfo.Name)) then
       ShowMessage('Unable to delete: C:\Download\'+DirInfo.Name);
   r := FindNext(DirInfo);
 end;
 SysUtils.FindClose(DirInfo);
 if not RemoveDirectory('C:\Download\') then
   ShowMessage('Unable to delete directory: C:\Download\');
end;

{ WinAPI }
procedure procedure DeleteDir2();
var lpFileOp: TSHFileOpStruct;
begin
 FillChar(lpFileOp,SizeOf(lpFileOp),0);
 lpFileOp.Wnd := Handle;
 lpFileOp.wFunc := FO_DELETE;
 lpFileOp.pFrom := PChar(Edit1.Text);
 lpFileOp.fFlags := FOF_NOCONFIRMATION;
 SHFileOperation(lpFileOp);
end;