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AJAX with better re-usability?

I have my AJAX split in two parts. The "AJHAX" function which has two values, the url of the file to load and then the function where I can specify where I want it to end up ("cFuntion" uses the function "loadToContent"):
First part:
function AJHAX(url, cFunction) {
var xhttp;
// compatible with IE7+, Firefox, Chrome, Opera, Safari
xhttp=new XMLHttpRequest();
xhttp.onreadystatechange = function() {
if (this.readyState == 4 && this.status == 200) {
cFunction(this);
}
};
xhttp.open("GET", url, true);
xhttp.send();
}
Second part:
function loadToContent(xhttp) {
document.getElementById('content').innerHTML =
xhttp.responseText;
}
So from the first part, I can call the functionality in my menu by adding the following to a link / an element:
onclick="AJHAX('page.php', loadToContent)"
However, with this I can only specify which page to load, not which element I want it loaded to. I tried to add it as a criteria for the second part of my code, like this. But to no avail:
function loadToContent(xhttp, targetElement) {
document.getElementById(targetElement).innerHTML =
xhttp.responseText;
}
Onclick:
onclick="AJHAX('menu.php', loadToContent(sidebar))"
Any suggestions?
Solution has been found (thanks to #schogges, please upvote!). Complete working example:
JS:
function AJHAX(url, targetElement, cFunction) {
var xhttp;
// compatible with IE7+, Firefox, Chrome, Opera, Safari
xhttp=new XMLHttpRequest();
xhttp.onreadystatechange = function() {
if (this.readyState == 4 && this.status == 200) {
cFunction(this, targetElement);
}
};
xhttp.open("GET", url, true);
xhttp.send();
}
function loadToContent(xhttp, targetElement) {
document.getElementById(targetElement).innerHTML =
xhttp.responseText;
}
HTML:
<div onclick="AJHAX('home.php', 'content', loadToContent);closeSidebar()">
Home</div>
So in the HTML, you just specify the page to load, the ID of the element to load the page into and then the "loadToContent" function that actually loads it into to element. As you can see, also have ";closeSidebar()" in there, and even if it does nothing for this example, I'll just leave it here to show anyone new that you can do it this way to add more than one function to an onclick-event. Mine simply just edits some CSS to hide the sidebar.

What about using a third parameter at AJHAX()?
Try this:
function AJHAX(url, target, cFunction) {
var xhttp;
// compatible with IE7+, Firefox, Chrome, Opera, Safari
xhttp=new XMLHttpRequest();
xhttp.onreadystatechange = function() {
if (this.readyState == 4 && this.status == 200) {
cFunction(this, target);
}
};
xhttp.open("GET", url, true);
xhttp.send();
}
function loadToContent(xhttp, targetElement) {
document.getElementById(targetElement).innerHTML =
xhttp.responseText;
}
and Onclick:
onclick="AJHAX('menu.php', 'sidebar', loadToContent)"

The line onclick="AJHAX('menu.php', loadToContent(sidebar))" doesn't work because it references an inert string.
Instead what you need to do is to reference a function, so it actually carries out the intended task: onclick = function () { AJHAX('https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js', loadToContent);};
Here is a snippet showcasing my answer:
//First part:
function AJHAX(url, cFunction) {
var xhttp;
// compatible with IE7+, Firefox, Chrome, Opera, Safari
xhttp = new XMLHttpRequest();
xhttp.onreadystatechange = function () {
if (this.readyState == 4 && this.status == 200) {
cFunction(this);
}
};
xhttp.open("GET", url, true);
xhttp.send();
}
//Second part:
function loadToContent(xhttp) {
console.log(xhttp.responseText);
alert(xhttp.responseText);
}
//TEST
var button = document.body.appendChild(document.createElement("h1"));
button.textContent = "Click me!";
button.onclick = function () {
AJHAX('https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js', loadToContent);
};

Javascript div refresh

I am trying to refresh a php script to show updated content as a database updates. I first built my php, then the code to refresh and then merge them. However, the script doesn't update. Anyone know why?
<script type="text/javascript"
src="http://code.jquery.com/jquery-1.10.1.min.js"></script>
<script>
$(document).ready(
function() {
setInterval(function() {
if(document.getElementById('gallery') != null){
function showLots() {
if (window.XMLHttpRequest) {
// code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp = new XMLHttpRequest();
} else {
// code for IE6, IE5
xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange = function() {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
document.getElementById("gallery").innerHTML = xmlhttp.responseText;
}
}
xmlhttp.open("GET","getuser.php",true);
xmlhttp.send();
}
}
}, 3000);
});
</script>
Thanks.

You did not called method showLots, First define it outside the function and than call it in setInterval

The issue with your code is that function showLots() is inside your if (document.getElementById('gallery') != null) conditional without the function actually executing.
Below is what your corrected code could could look like by moving the function showLots() definition up. showLots() is then called inside where you originally had the definition.
<script src="http://code.jquery.com/jquery-1.10.1.min.js"></script>
<script>
function showLots() {
if (window.XMLHttpRequest) {
// code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp = new XMLHttpRequest();
} else {
// code for IE6, IE5
xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange = function() {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
document.getElementById("gallery").innerHTML = xmlhttp.responseText;
}
}
xmlhttp.open("GET","getuser.php",true);
xmlhttp.send();
}
$(document).ready(function () {
setInterval(function () {
if (document.getElementById('gallery') !== null) {
showLots();
}
}, 3000);
});
</script>

What causes error in IE7?

I am using this JS code to reach a list of cities. It works in fireworks, chrome .e.t.c. But in ie7 it does not. the line document.getElementById(oDiv).innerHTML=xmlhttp.responseText; causes the error.
When I change "responseText" to "readyState", "statusText", "readyState" the scripts works. Only "responseText" causes problem.
What is the problem here?
function showAjax(oDiv, countrycode, dowhat) {
if (oDiv == "") {
document.getElementById(oDiv).innerHTML = "";
return;
}
if (window.XMLHttpRequest) { // code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp = new XMLHttpRequest();
} else { // code for IE6, IE5
xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.open('POST', 'ajax.php?dowhat=' + dowhat + '&countrycode=' + countrycode, true);
xmlhttp.onreadystatechange = function () {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
document.getElementById(oDiv).innerHTML = xmlhttp.responseText;
//document.getElementById(oDiv).innerHTML=xmlhttp.readyState;
}
}
xmlhttp.send();
}
Click
<div id=citytd></div>

IE7 (and before, and IE8 in "compatibility" mode) has issues with getElementById, where it considers some things IDs that it shouldn't. I suspect you have a global variable, or another element with name="citytd", and IE is pick that up instead (even though, again, it shouldn't). More: ...by any other name, would smell as sweet

ajax internet explorer onchange

My ajax script for loading the second select box, works in firefox and chrome, but internt explorers cant handle it. I call the onChange function from my select box and give the value from the select box to the function.
Code:
function getXMLHTTP()
{
var xmlhttp;
if (window.XMLHttpRequest)
{// code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp=new XMLHttpRequest();
}
else
{// code for IE6, IE5
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
return xmlhttp;
}
function getType(categoryName)
{
var strURL="includes/get.php?c="+categoryName+"&sid="+Math.random();
var req = getXMLHTTP();
if (req) {
req.onreadystatechange = function() {
if (req.readyState == 4) {
// only if "OK"
if (req.status == 200)
{document.getElementById('type').innerHTML=req.responseText;
} else {
alert("There was a problem while using XMLHTTP:\n" + req.statusText);
}
}
}
req.open("GET", strURL, true);
req.send(null);
}
}
My second question is, is it possible to send the text between the options tag instead of the value in the options tag?

For your 1st question, I assume your if (req) returns false. Which IE version are you using? Try to add debug codes in getXMLHTTP() function to start diagnosing the codes. Try this solution provided by Microsoft: http://msdn.microsoft.com/en-us/library/ms537505(v=vs.85).aspx
I try not to repeat other's answer. Here is the answer for obtaining text in selected option tag : Getting the text from a drop-down box

Parse XML data on page load & insert into div using AJAX / Javascript

I am working on a page that uses javascript / AJAX to parse xml from a file. I need to be able to parse a url on the loading of a page and insert it into a div. I have the script written but I need help getting 2 things:
1) having it parse an XML file and load that data into a div on page load
2) the option to click a link and load that data into the same div instead of what was there when the page loaded.
I am using an external script to do this & embeded a link to it in my page
HTML example to request data:
<div id="rightcolumn">
<button onclick="loadXMLDoc('cd_catalog.xml')">Get CD info</button>
</div>
How do I change that to load #1 when the page loads & #2 when a link is clicked?
For the script, do I need anything special at the top to make sure it loads properly? jQuery has $(document).ready(function() {//GUTS}, do I need something similar with AJAX?
My Script
function loadXMLDoc(url){
if (window.XMLHttpRequest)
{// code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp=new XMLHttpRequest();
}
else
{// code for IE6, IE5
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange=function(){
if (xmlhttp.readyState==4 && xmlhttp.status==200)
{
var anno= xmlhttp.responseXML.documentElement.getElementsByTagName("anno");
// Parser Guts
}
document.getElementById('rightcolumn').innerHTML=txt;
}
}
xmlhttp.open("GET","url",true);
xmlhttp.send();

Usage
<!-- when the user clicks -->
<button onclick="ajax('#ELEMENT','cd_catalog.xml')">Get CD info</button>
// when the page loads
window.onload = function () {
ajax('#ELEMENT', 'cd_catalog.xml');
};
or you can place a script tag at the bottom of the page, or use the dom ready event
Code
function getXmlHttpObject() {
var xmlHttp;
try {
// Firefox, Opera 8.0+, Safari
xmlHttp = new XMLHttpRequest();
} catch (e) {
// Internet Explorer
try {
xmlHttp = new ActiveXObject("Msxml2.XMLHTTP");
} catch (e) {
xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
}
}
if (!xmlHttp) {
alert("Your browser does not support AJAX!");
}
return xmlHttp;
}
function ajax(el, url, onSuccess, onError) {
if (typeof el == "string")
el = document.getElementById(el);
var xmlHttp = getXmlHttpObject();
xmlHttp.onreadystatechange = function() {
if (this.readyState === 4) {
// onSuccess
if (this.status === 200 ) {
if (el)
el.innerHTML = this.responseText;
if (typeof onSuccess == 'function')
onSuccess(this.responseText);
}
// onError
else if(typeof onError == 'function') {
onError();
}
}
};
xmlHttp.open("GET", url, true);
xmlHttp.send(null);
return xmlHttp;
}​