I am using SimpleXMLElement() to obtain data from a website, which is used to embed data. The code I am using is as follows:
$rss = new SimpleXMLElement('http://eliteprospects.com/rss_player_stats2.php?player='.$player_array[0]['embed_stats'], null, true);
foreach($rss->xpath('channel/item') as $item)
{
echo utf8_decode($item->description);
}
This works great, except for one issue, the data loads exceptionally slow from the other site. The page load goes from approximately 0.5-1s to 2.5-3s.
Is there a method that I can use, to load the asynchronously, or is there a faster function I should be using instead?
An idea that came to mind was to load a separate page within an iFrame after the initial page load, or is there a better method?
Is there a method that I can use, to load the asynchronously, or is
there a faster function I should be using instead?
Unfortunately, there is nothing to do about the long response time (trivially assuming that connection speed in not archaic). Also echoing out the results all at once might slow down the browser rendering and thus the page load time.
AJAX fits nicely here - wait for window.onload and trigger the AJAX call to your webservice (holds the snippet from question) to prepare the output buffer and return the response to browser. Afterwards set/replace the innerHTML value of selected DOM element with the response.responseText.
Pseudo-code
window.onload = function()
{
var url = 'http://example.com/webserice';
Ajax.get(url, function(response)
{
var responseText = response.responseText;
document.getElementById('someid').innerHTML = responseText;
}
}
The snippet I am using in pure JS, although jQuery has a lot more appealing way to do it
Ajax = {
request : {},
createRequest : function()
{
var request = false;
if (window.XMLHttpRequest)
{
request = new XMLHttpRequest();
}
else
{
if (window.ActiveXObject)
{
request = new ActiveXObject('MSXML2.XMLHTTP.3.0');
}
else
{
request = false;
}
}
return request;
},
get : function(page, callback)
{
var self = this;
var request = this.createRequest();
if (! page)
{
return false;
}
request.onreadystatechange = function()
{
if (request.readyState == 4 && request.status == 200)
{
delete self.request;
if (typeof callback == 'function')
{
callback(request);
}
else
{
self.update(request, callback);
}
var regex = /<script\b.*?>([\s\S]*?)<\/scri/ig;
var match;
while (match = regex.exec(request.responseText))
{
eval(match[1]);
}
}
}
request.open('GET', page, true);
request.setRequestHeader('X-Requested-With', 'ajax');
request.send(null);
}
}
Related
Please read below my scenario…
I have a PHP file wherein I have javascript within it..
<?php
echo ‘<script>’;
echo ‘window.alert(“hi”)’;
echo ‘</script>’;
?>
On execution of this file directly, the content inside the script is executed as expected. But if this same page is being called via ajax from another page, the script part is NOT executed.
Can you please let me know the possible reasons.
(note: I’m in a compulsion to have script within php page).
When you do an AJAX call you just grab the content from that page. JavaScript treats it as a string (not code). You would have to add the content from the page to your DOM in your AJAX callback.
$.get('/alertscript.php', {}, function(results){
$("html").append(results);
});
Make sure you change the code to fit your needs. I'm supposing you use jQuery...
Edited version
load('/alertscript.php', function(xhr) {
var result = xhr.responseText;
// Execute the code
eval( result );
});
function load(url, callback) {
var xhr;
if(typeof XMLHttpRequest !== 'undefined') xhr = new XMLHttpRequest();
else {
var versions = ["MSXML2.XmlHttp.5.0",
"MSXML2.XmlHttp.4.0",
"MSXML2.XmlHttp.3.0",
"MSXML2.XmlHttp.2.0",
"Microsoft.XmlHttp"]
for(var i = 0, len = versions.length; i < len; i++) {
try {
xhr = new ActiveXObject(versions[i]);
break;
}
catch(e){}
} // end for
}
xhr.onreadystatechange = ensureReadiness;
function ensureReadiness() {
if(xhr.readyState < 4) {
return;
}
if(xhr.status !== 200) {
return;
}
// all is well
if(xhr.readyState === 4) {
callback(xhr);
}
}
xhr.open('GET', url, true);
xhr.send('');
}
All,
I have a fairly simple javascript script that changes some text in my html page. The weird thing is that the data is only changed if I have an alert. If I hide the alert as a comment, the data doesn't appear on the webpage. To be specific, here are the relevant pieces of the JS code:
var index=0;
var xmlObject=null;
function calcIndex(){
return index++;
}
function showNextName(){
retrieveNextName();
var someText = xmlObject.getElementsByTagName("name")[0].childNodes[0].nodeValue;
document.getElementById('nextName').innerHTML=someText;
}
function retrieveNextName(){
var index=calcIndex();
request = createRequest();
if (request == null) {
alert("Unable to create request");
return;
}
var url= "Ajax_retrieveName.php?index=" + index;
request.open("GET", url, true);
request.onreadystatechange = createXml;
request.send(null);
alert("abc");
//If the alert above is missing, the html is not modified...
}
function createXml() {
if (request.readyState == 4) {
if (request.status == 200) {
xmlObject = request.responseXML;
}else{
return;
}
}else{
return;
}
}
Does anyone know what might be causing that?
The problem is that XML object is not immediately available, because the request isn't finished yet, so the callback hasn't been called yet. (Alerting allows the request to finish in the time before you clock the alert box away.)
A better solution would be to have an updateElementHtml(newHtml) function and call that from within the callback.
i have page that do add new record by old way ajax, this code was add new record and return the error or done result message , how can i print the message on div and print result on other div. i try but some one tell me to use JOSN, how can i do that
<script language="JavaScript">
$(document).ready(function() {
});
$("#closeerr").live('click', function() {
$("#gadget").hide();
});
var HttPRequest = false;
function doCallAjax(Mode,Page,ID) {
HttPRequest = false;
if (window.XMLHttpRequest) { // Mozilla, Safari,...
HttPRequest = new XMLHttpRequest();
if (HttPRequest.overrideMimeType) {
HttPRequest.overrideMimeType('text/html');
}
} else if (window.ActiveXObject) { // IE
try {
HttPRequest = new ActiveXObject("Msxml2.XMLHTTP");
} catch (e) {
try {
HttPRequest = new ActiveXObject("Microsoft.XMLHTTP");
} catch (e) {}
}
}
if (!HttPRequest) {
alert('Cannot create XMLHTTP instance');
return false;
}
var url = 'AjaxItemsGroupsRecord.php';
var pmeters = "titems_groups_GroupName=" + encodeURI( document.getElementById("items_groups_GroupName").value) +
"&titems_groups_sys_type_ID=" + encodeURI( document.getElementById("items_groups_sys_type_ID").value ) +
'&myPage='+Page +
"&tID=" + ID +
"&tMode=" + Mode;
HttPRequest.open('POST',url,true);
HttPRequest.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
HttPRequest.setRequestHeader("Content-length", pmeters.length);
HttPRequest.setRequestHeader("Connection", "close");
HttPRequest.send(pmeters);
HttPRequest.onreadystatechange = function()
{
if(HttPRequest.readyState == 3) // Loading Request
{
document.getElementById("mySpan").innerHTML = "looding";
}
if(HttPRequest.readyState == 4) // Return Request
{
document.getElementById("mySpan").innerHTML = HttPRequest.responseText;
}
}
}
</script>
If jQuery is an option... As mentioned in my comment I'd recommend you try out jQuery http://jquery.com/ as you look to be fairly new to JavaScript.
It makes AJAX requests a lot simpler and you don't have to worry about making XMLHttpRequest work cross browser.
For making an actual AJAX request see: http://api.jquery.com/jQuery.ajax/
Now if you want to use JSON you need to convert the data to return in your PHP script.
This is really easy, you just pass the data in json_encode() and it will convert the data to a JSON string. You then just echo it out so that it's returned to the AJAX request.
echo json_encode($data);
Now if you've setup your AJAX request to expect a JSON response then you can use the data that comes back. So something like this:
$.ajax({
url: 'request.php', // the php you want to call
dataType: 'json' // the type of data being returned
}).done(function(json) {
// you now have a json object
});
If you can only use native JavaScript...
If you can't use jQuery then it roughly works the same way. You'd have the code in your example for the AJAX request. You'd still use json_encode() in the PHP. The only difference is when the data comes back you'd need to parse it like so:
JSON.parse(json);
For more info on this last bit checkout: Parse JSON in JavaScript?
im trying to get a bit of html to refresh every 1 second with AJAX, I made this code my self with bits from different websites that I found. Im trying to understand how it all works.
I want to be able to refresh the page without reloading it in the browser and I want the JS function AJAXdisplay(); to run every one second with the variables I send to AJAXreturn(); when I call it.
When I call AJAXreturn(); I want it to run AJAXdisplay(); once to print out the html from my php file, on my body if the index file I want somthing like this
<body onClick=:AJAXdisplay(same variables as used when the page was made);">
</body>
here is my code:
function getHTTPObject(){
if (window.ActiveXObject) {
return new ActiveXObject("Microsoft.XMLHTTP");
}
if (window.XMLHttpRequest){
return new XMLHttpRequest();
}
else {
alert("Your browser does not support AJAX.");
return null;
}
}
function AJAXsend(url) {
httpObject = getHTTPObject();
if (httpObject != null) {
httpObject.open("POST",url);
httpObject.send(null);
}
}
function AJAXreturn(url,pageName){
httpObject = getHTTPObject();
if (httpObject != null) {
if (navigator.appName != "Microsoft Internet Explorer") {
history.replaceState("", "", "index.php?page=" + pageName)
}
httpObject.open("POST",url);
httpObject.send(null);
AJAXdisplay(httpObject,url,pageName);
}
}
function AJAXdisplay(httpObjectIn,urlIn, pageNameIn){
httpObjectIn.onreadystatechange = function(){
if(httpObjectIn.readyState == 4){
document.getElementById('outputHTML').innerHTML = httpObjectIn.responseText;
AJAXdisplay('function(httpObjectIn,urlIn,pageNameIn)',1000);
}
}
}
To make javascript refresh, you should use the setInterval(); function. Here's what your looking for:
var timer = setInterval ("AJAXdisplay(variable);", 1000);
And if you ever need to stop the refresh you use:
clearInterval (timer);
How can I use javascript to send a one way message to php? I would like to get the browser information from javascript and just send it to php in the background. I know I can get some of this from php, but I'd rather use javascript. Is there a way to do this without a framework like jquery?
Yes, you can do it with something like this:
function xmlhttpPost(strURL) {
var xmlHttpReq = false;
var self = this;
// Mozilla/Safari
if (window.XMLHttpRequest) {
self.xmlHttpReq = new XMLHttpRequest();
} else if (window.ActiveXObject) {
// IE
self.xmlHttpReq = new ActiveXObject("Microsoft.XMLHTTP");
}
self.xmlHttpReq.open('POST', strURL, true);
self.xmlHttpReq.onreadystatechange = function() {
if (self.xmlHttpReq.readyState == 4) {
alert('Here goes something');
self.xmlHttpReq.send('browser info here');
}
}
}
This will send "browser info here" as POST in the php page you pass to the function as url. I didnt test it though
You would have to submit an AJAX request to a PHP script. Yes, you could do it without using a framework but I wouldn't advise it.
You need to make an AJAX call to a PHP page, preferably using POST. Any data you want to send needs to be sent along with the request.
I recommend using a framework such as jQuery, but if you insist on using raw JavaScript, you want to research XMLHttpRequest.
// fix for older IE versions
// see http://blogs.msdn.com/b/xmlteam/archive/2006/10/23/using-the-right-version-of-msxml-in-internet-explorer.aspx
if( typeof window.XMLHttpRequest === 'undefined' &&
typeof window.ActiveXObject === 'function') {
window.XMLHttpRequest = function() {
try { return new ActiveXObject('Msxml2.XMLHTTP.6.0'); } catch(e) {}
try { return new ActiveXObject('Msxml2.XMLHTTP.3.0'); } catch(e) {}
return new ActiveXObject('Microsoft.XMLHTTP');
};
}
function postData(url, data, errhandler) {
var req = new XMLHttpRequest;
req.onreadystatechange = function() {
if(this.readyState === 4 && this.status !== 200 && errhandler)
errhandler(this);
};
try {
req.open('POST', url, true); // async post request
req.send(data);
}
catch(e) {
if(errhandler)
errhandler(req);
}
}