how to store a xmlhttprequest into a variable - javascript

I have a quick question that you brainy guys perhaps have the answer to.
Why does this work
<html>
<head>
<script type="text/javascript">
var xmlhttp;
function loadXMLDoc(url,cfunc)
{
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=cfunc;
xmlhttp.open("GET",url,true);
xmlhttp.send();
}
function myFunction()
{
loadXMLDoc("ajax_info.txt",function()
{
if (xmlhttp.readyState==4 && xmlhttp.status==200)
{
document.getElementById("myDiv").innerHTML=xlmhttp.responseText;
}
});
}
</script>
</head>
<body>
<div id="myDiv"><h2>Let AJAX change this text</h2></div>
<button type="button" onclick="myFunction()">Change Content</button>
</body>
</html>
but if I replace
document.getElementById("myDiv").innerHTML=xlmhttp.responseText;
whit this
var txt=xlmhttp.responseText;
document.getElementById("myDiv").innerHTML=txt;
it don't work anymore, txt is
undefined
. How can I store the xlmhttp.responseText into a string, or into a variable that I can perform a search on? Please give an example on how I can do it. Thanks in advance =)

Might be because you have misspelled variable "xmlhttp" - you have "xlmhttp" in your code.

Related

AJAX won't get PHP - echo

So I'm trying to build a pretty simple website, to learn basic webdesign. It's just a random quote generator - you click on a button and it prints some famous quote. Anyway, I try to use ajax to get the quote, so I use this function:
function loadXMLDoc()
{
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");
}
xmlhttp.onreadystatechange=function()
{
if (xmlhttp.readyState==4 && xmlhttp.status==200)
{
document.getElementById("quote").innerHTML=xmlhttp.responseText;
}
}
xmlhttp.open("GET","RandomQuote.php",true)
xmlhttp.send();
}
but no matter what I type into RandomQuote.php, even if it's something like :
<?php
echo 'Hello, world';
?>
nothing shows up in the quote "div', it just becomes blank. I really have no idea what's the problem here. Thanks for the help!
Well, I'm not sure about much, but are you calling your function? You put your ajax inside loadXMLDoc() , so you probably have to call it. Another way is to put your ajax into an addEventListener so when a user clicks on something, it'll execute. If that's not the problem, try making sure your element in your html page with the id of "quote" is spelled correctly. Sometimes the latter scenario is always the problem for me.
$.get( "RandomQuote.php", function( data ) {
$( "#quote" ).html( data );
console.log( "Load was performed." );
});
Don't forget to include jQuery.
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
This is my ajax function, try to use it:
/**
* #function ajax Send ajax-request with post
* #param {string} xmlpage Target url
* #param {string} data Post parameters (like param1=val1&param2=val2...)
* #param {Function} callback
* #return {null}
*/
function ajax(xmlpage, data, callback)
{
var xmlh = null;
if(window.XMLHttpRequest)
xmlh = new XMLHttpRequest();
else
try
{
xmlh = new ActiveXObject("Msxml2.XMLHTTP");
}
catch(ex)
{
xmlh = new ActiveXObject("Microsoft.XMLHTTP");
}
if(xmlh)
{
xmlh.open("post", xmlpage, true);
xmlh.onreadystatechange = function(x)
{
if(xmlh.readyState==4 && typeof callback !== 'undefined')
callback(xmlh.responseText);
}
xmlh.setRequestHeader("Accept-Language","ru, en");
xmlh.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xmlh.send(data);
}
}
Following test files using your code from the question. It is working perfectly. Either you are missing something or its a browser issue. I tested on Mozilla. To be sure of browser independent code use jQuery for Ajax call
test.html
<html>
<script>
function loadXMLDoc()
{
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");
}
xmlhttp.onreadystatechange=function()
{
if (xmlhttp.readyState==4 && xmlhttp.status==200)
{
document.getElementById("quote").innerHTML=xmlhttp.responseText;
}
}
xmlhttp.open("GET","RandomQuote.php",true)
xmlhttp.send();
}
</script>
<div id="quote"></div>
<input type="button" value="Click Me" onclick="loadXMLDoc()"/>
</html>
RandomQuote.php
<?php
echo 'hi';
Update: jQuery version
<html>
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script>
function loadXMLDoc()
{
$.get( "RandomQuote.php", function( data ) {
$( "#quote" ).html( data );
});
}
</script>
<div id="quote"></div>
<input type="button" value="Click Me" onclick="loadXMLDoc()"/>
</html>

Ajax call to get Data

Dear I want to get Variable Value form PHP Value, and I want to write an ajax call in Java Script, tags,
How it is possible,
I want to get Value from get_result.php file,
and I have following code in get_result.php:
<?php
echo $val="abc";
?>
and I wrote follwing code in another file named ajax.php:
<script>
if (window.XMLHttpRequest)
{
xmlhttp=new XMLHttpRequest();
}
else
{
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
var url="<?php echo "get_result.php"; ?>";
xmlhttp.open("GET", url, false);
xmlhttp.send(null);
var ok xmlhttp.responseText;
alert(ok);
</script>
is there any bug and Where?
I want to get value from get_result.php file and show this value in an Alert;
You can use jQuery. but for your code, you didn't assign the response
<script>
if (window.XMLHttpRequest)
{
xmlhttp=new XMLHttpRequest();
}
else
{
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
var url="get_result.php";
xmlhttp.open("GET", url, false);
xmlhttp.send(null);
var ok = xmlhttp.responseText;
alert(ok);
The below code will help you in returning the value from the php page
<script>
function myfun()
{
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");
}
xmlhttp.onreadystatechange=function()
{
if (xmlhttp.readyState==4 && xmlhttp.status==200)
{
var demo=xmlhttp.responseText;
alert(demo);
}
}
xmlhttp.open("GET","result.php",true);
xmlhttp.send();
}
</script>
body
<body>
<input type="button" onclick="myfun();"/>
</body>

How to autorefresh XML in Javascript

Below is the code that I am having trouble with -
<script type="text/javascript" language="javascript">
function loadXMLDoc()
{
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");
}
xmlhttp.onreadystatechange=function()
{
if (xmlhttp.readyState==4 && xmlhttp.status==200)
{
document.getElementById("myDiv").innerHTML=xmlhttp.responseText;
}
}
xmlhttp.open("GET","<%=StatsURL%>",true);
xmlhttp.send();
}
function timedRefresh(timeoutPeriod) {
setTimeout(function(){loadXMLDoc(); autoRefresh();},timeoutPeriod);
}
</script>
And this is called in -
<body onload="JavaScript:timedRefresh(50000);">
<div id="myDiv"></div>
</body>
I want to refresh the page/load the XML every 5 seconds however the above code does not appear to work. I have read (http://www.htmlgoodies.com/tutorials/getting_started/article.php/3479551/Reloading-The-Page.htm) that you can use META tags ()to refresh the page as well.
Any help to get this code working would be greatly appreciated.
ANSWER
Change the code to the below -
window.onload = startInterval();
function startInterval()
{
setInterval("loadXMLDoc();", 5000);
}
That's because you refresh the page every 50 secs (50000 milliseconds). Change it to 5000 and it'll work.

Cannot get a 'bad response' from Ajax call

I'm trying to use Ajax to tell me whether my server is up or not. I've made a simple page with just one Ajax call. When the server is up, it comes back with the xmlhttp.responseText. IF the server is down it is supposed to say "SERVER DOWN"...but when I load the page, then turn off Apache, it still says that the server is up. Is there some other way I should be doing this?
<!DOCTYPE html>
<html>
<head>
<script>
var xmlhttp;
var url = "http://192.168.0.5/ajax_info.txt";
function loadXMLDoc(url,cfunc)
{
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=cfunc;
xmlhttp.open("GET",url,true);
xmlhttp.send();
}
function myFunction()
{
loadXMLDoc(url,function()
{
if (xmlhttp.readyState==4 && xmlhttp.status==200)
{
document.getElementById("myDiv").innerHTML = xmlhttp.responseText;
}
else
{
document.getElementById("myDiv").innerHTML = "Server Down!";
}
});
}
</script>
</head>
<body>
<div id="myDiv"><h2>Let AJAX change this text</h2></div>
<button type="button" onclick="myFunction()">Change Content</button>
</body>
</html>
Thanks for the help
Your page is probably cached, use a cache buster in the url. e.g.
xmlhttp.open("GET",url+'?_dc='+(new Date()).getTime(),true);

How do you make this ajax example work on opera and firefox?

I have a quick question, the following only works on IE 7 and above, how can I make it work on firefox and opera aswell?
<html>
<head>
<script type="text/javascript">
function loadXMLDoc()
{
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");
}
xmlhttp.onreadystatechange=function()
{
if (xmlhttp.readyState==4 && xmlhttp.status==200)
{
document.getElementById("myDiv").innerHTML=xmlhttp.responseText;
}
}
xmlhttp.open("GET","http://www.tdsoft.se/index.html",true);
xmlhttp.send();
}
</script>
</head>
<body>
<div id="myDiv"><h2>Let AJAX change this text</h2></div>
<button type="button" onclick="loadXMLDoc()">Change Content</button>
</body>
</html>
Edit
Thanks for all your answers, now I just have another question regarding the followng code
<html>
<head>
<script type="text/javascript">
function loadXMLDoc()
{
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");
}
xmlhttp.onreadystatechange=function()
{
if (xmlhttp.readyState==4 && xmlhttp.status==200)
{
return xmlhttp.responseText;
}
}
xmlhttp.open("GET","index.html",true);
xmlhttp.send();
}
</script>
</head>
<body>
<div id="myDiv"><h2>Let AJAX change this text</h2></div>
<button type="button" onclick="loadXMLDoc()">Change Content</button>
</body>
</html>
Now I want to search through the xmlhttp.responseText (in other words call the function loadXMLDoc()) for key words, like for example "testfile" and if it exists multiple example "testfile_1" and "testfile_2"....."testfile_n" then "doSomething"
like this
function searchADocument(wordToSearchFor){
int numberOfTimesWordOccurs=0;
var thePageToSearchThrough [] = loadXMLDoc();
for (i=0; i<thePageToSearchThrough.length; i++){
if(thePageToSearchThrough[i]==wordToSearchFor)
numberOfTimesWordOccurs++;
}
If (wordToSearchFor > 1)
document.write(" testfile_1" testfile_2 testfile_n
)
Else
window.location="http://selnc05.go.se:8080/component_test/build/testfile.html";
}
I don't know where to start since I don't know what type xmlhttp.responseText is, can I store it in an array and scan it using for loop etc?
Thanks in advance. =)
Try something like this:
ajax("http://www.tdsoft.se/index.html", function(data) {
document.getElementById("myDiv").innerHTML = data;
});
Code
function getXmlHttpObject() {
var xmlHttp;
try {
xmlHttp = new XMLHttpRequest();
} catch (e) {
try {
xmlHttp = new ActiveXObject("Msxml2.XMLHTTP");
} catch (e) {
xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
}
}
return xmlHttp;
}
function ajax(url, onSuccess, onError) {
var xmlHttp = getXmlHttpObject();
xmlHttp.onreadystatechange = function () {
if (this.readyState == 4) {
if (this.status != 200) {
if (typeof onError == 'function') {
onError(this.responseText);
}
}
else if (typeof onSuccess == 'function') {
onSuccess(this.responseText);
}
}
};
xmlHttp.open("GET", url, true);
xmlHttp.send(null);
return xmlHttp;
}​

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