javascript - How to always refresh file loaded by ajax, avoiding cached file -

first load external javascript file following code (it appends ext_chat.js script source current dom):

var protocol = ('https:' == document.location.protocol ? 'https://' : 'http://'); (function(d, t, p) {    var g = d.createelement(t),       s = d.getelementbyid('chat_script');    g.src = p + 'mydomain.lc/js/ext_chat.js';    s.parentnode.insertbefore(g, s.nextsibling); }(document, 'script', protocol)); 

inside ext_chat.js. here i'm including css file:

function r(f) {  /in/.test(document.readystate) ? settimeout('r(' + f + ')', 9) : f() }  r(function () {     includecssfile(getbaseurl() + '/css/ext_chat.css')); // getbaseurl() gives correct url });  function includecssfile(href) {     var head_node = document.getelementsbytagname('head')[0];     var link_tag = document.createelement('link');     link_tag.setattribute('rel', 'stylesheet');     link_tag.setattribute('type', 'text/css');     link_tag.setattribute('href', href);     link_tag.setattribute('media', 'screen');     head_node.appendchild(link_tag); } 

on first load, css file included fine. after first time, when page loaded changes ext_chat.css file not reflected, , cached file being used instead. how can force css file reload every time page loads, instead of referring cached one?

first things first, don't use eval version of settimeout. use .bind instead.

/in/.test(document.readystate) ? settimeout(r.bind(null, f), 9) : f() 

now, avoid file caching should attach random query string end of uri. you'll see ?v=123456789 or effect. can use timestamp in case.

r(function () {     includecssfile(getbaseurl() + '/css/ext_chat.css?v=' + date.now())); // getbaseurl() gives correct url }); 

reading material:

• function.prototype.bind()
• date.now()