$file =  file(file.txt);

                              

                              $res = $file[0].$file[1].$file[2];

                              

                              echo $res;

                              

                            

                              

                              $text = file_get_contents("file.txt");

                              $text = str_replace("\r\n", "", $text);

                              echo $text;

                            

                              $file =  file(file.txt);      

                              $res = "";    

                              foreach ($file as $k => $v) {

                              $res .= $v;

                              }

                              echo $res;  
                            

                              for($i = 0; $i < count($file); $i++){

                              ...

                              }