https://www.billoreilly.com/pg/jsp/common/utils/js/ajaxpage.js

1// JavaScript Document
2
3/***********************************************
4* Dynamic Ajax Content- © Dynamic Drive DHTML code library (www.dynamicdrive.com)
5* This notice MUST stay intact for legal use
6* Visit Dynamic Drive at http://www.dynamicdrive.com/ for full source code
7***********************************************/
8
9var bustcachevar=1 //bust potential caching of external pages after initial request? (1=yes, 0=no)
10var loadedobjects=""
11var rootdomain="http://"+window.location.hostname
12
13function ajaxpage(url, containerid){
14var page_request = false
15if (window.XMLHttpRequest) // if Mozilla, Safari etc
16page_request = new XMLHttpRequest()
17else if (window.ActiveXObject){ // if IE
18try {
19page_request = new ActiveXObject("Msxml2.XMLHTTP")
20} 
21catch (e){
22try{
23page_request = new ActiveXObject("Microsoft.XMLHTTP")
24}
25catch (e){}
26}
27}
28else
29return false
30page_request.onreadystatechange=function(){
31loadpage(page_request, containerid)
32}
33if (bustcachevar) //if bust caching of external page
34var bustcacheparameter=(url.indexOf("?")!=-1)? "&"+new Date().getTime() : "?"+new Date().getTime()
35page_request.open('GET', url+bustcacheparameter, true)
36page_request.send(null)
37}
38
39function loadpage(page_request, containerid){
40if (page_request.readyState == 4 && (page_request.status==200 || window.location.href.indexOf("http")==-1))
41document.getElementById(containerid).innerHTML=page_request.responseText
42}
43
44function loadobjs(){
45if (!document.getElementById)
46return
47for (i=0; i<arguments.length; i++){
48var file=arguments[i]
49var fileref=""
50if (loadedobjects.indexOf(file)==-1){ //Check to see if this object has not already been added to page before proceeding
51if (file.indexOf(".js")!=-1){ //If object is a js file
52fileref=document.createElement('script')
53fileref.setAttribute("type","text/javascript");
54fileref.setAttribute("src", file);
55}
56else if (file.indexOf(".css")!=-1){ //If object is a css file
57fileref=document.createElement("link")
58fileref.setAttribute("rel", "stylesheet");
59fileref.setAttribute("type", "text/css");
60fileref.setAttribute("href", file);
61}
62}
63if (fileref!=""){
64document.getElementsByTagName("head").item(0).appendChild(fileref)
65loadedobjects+=file+" " //Remember this object as being already added to page
66}
67}
68}