var  rev,str:string;
  ss: TStringStream;
  s :ANSIstring;
  f:textfile; 
  begin
  
  assignfile(f,getcurrentdir+'/txtfile.txt);
  reset(f);
  readln(f,str);
  closefile(f);

  ss := TStringStream.Create('');
  s  :=str;
  ss.WriteString('txt='+s);

   http1:=TIdHTTP.Create(nil);
  rev:=http1.Post('http://vkontakte.ru/wall.php', ss);
  http1.Free;