.ajaxStart & .ajaxStop triger with every ajax request

.ajaxStart & .ajaxStop triger with every ajax request

hi
i have a searchbox at the top of my page, using ajax. for sjowing preloader icon, during search process i used something like this:
  1.      //preloader icon
         $('#txt_srch').ajaxStart(function() {
            $('#txt_srch').addClass('txt_srch_preloader');
         }).ajaxStop(function() {
            $('#txt_srch').removeClass('txt_srch_preloader');
         });





now this preloader shows, everywhere i use ajax in my site. i know despite mentioning $('#txt_srch') before ajaxStart, this method triggers with every ajax requet. but i wonder what are my other options, without using .ajaxStart method?