Ajax refresh page content instead of div content - ajax

Is there a way to refresh the entire page content instead of just a div?

what exactly do you want here? you can write 1 javascript line to refresh entire page
window.location.reload()

You can replace the content of the body tag. It's just like replacing the content of an ordinary div. To access the body tag use document.body or document.getElementsByTagName('body')[0].
If you do a normal page reload with window.location you will have the CSS and JavaScript in the head reloaded, so that will take more resources.

You can do something like this to send the browser to a new URL:
window.location = "http://www.google.com/"
But, at that point, you're kind of defeating the point of AJAX. Most of the time, you'd want to download only the data you need from the server, and rewrite the contents of only those parts of the page that change. It's generally a better experience for the user, that way.

Related

how to get information from php without refreshing the page

hi
sorry for the bad title but I'm not 100% sure what I need for this problem
I created a welcome page and then when you click on links you get more information, for example:
Click Me
And then the php would get the information based on the id.
so the information received is reloaded on the page after the pages refreshes
what I would like to be able to do is when user clicks on the link, use jquery to not allow the link to run but still run the url in the background (without refreshing the page)
I have no idea where to start from so I really hope you could help
thanks
In a nutshell, it's called Ajax: sending an HTTP request to your server through javaScript, and receiving a response which can contain results, data, or other information.
You mention jQuery, here are the docs about that:
http://api.jquery.com/jQuery.get/
http://api.jquery.com/jQuery.post/
are convenience methods, which encapsulate $.ajax with preset options.
http://api.jquery.com/category/ajax/ is an overview of the whole system in jQuery.
The basics go like
//include jquery, etc.
$(document).ready(function(){
$('#some_element').click(function(){
$.get('some_url_on_your_server.php',{'data':'whatever params'},function(data){
do_something();//
},'json');
});
This will bind an element to make an Ajax call on click, and then you use the function ('success' function, in $.ajax) to handle the json data.
Have your server send back the data in JSON by using json_encode in php. Be sure to send the right header back, like
<?php
header('Content-Type: application/json');
echo json_encode($some_array);
exit;
There's a lot of resources on the web and SO for learning about Ajax, it's a big topic. Best of luck.
Make a JavaScript function, like sendData(linkId) and then each tag would have an onclick event called sendData(this). SendData(linkId) can then do an HTTPRequest (also known as an asynchronous or AJAX request) to a php file, let's call it handler.php, which receives GET or POST methods. I prefer using the prototype framework to do this kind of thing (you can get it at prototypejs.org).
Okay, now that I have said all that, let's look into the nitty-gritty of how to do this (way simplified for illustrative purposes).
Download the prototype script, save it on your server (like prototype/prototype.js, for example) and then put somewhere in your html <script type='text/javascript' language='Javascript' src='prototype/prototype.js'></script>
Your tags would look like this:<a id='exampleLink' onclick = 'sendData(this)'>Click me!</a>
You need JavaScript to do this: function sendData(tagId){
var url = 'handler.php?' + 'id=' + tagId;
var request = new AJAX.Request(url, {method = 'get'});
}
Finally, you need a php file (let's call it handler.php) that has the following: <?php
$tag_to_get = $_GET['tagId'];
do_a_php_function($tag_to_get);
?>
That's it in a nutshell, but it's worth mentioning that you should give your user some sort of feedback that clicking link did something. Otherwise he will click the link furiously waiting for something to happen, when it is actually doing just what its supposed to but in secret. You do that by making your php script echo something at the end, like 'Success!', and then add an onSuccess parameter to your JavaScript's new Ajax.Request. I'll let you read how to do that on your own because the prototype website explains how to receive a response from the handler and put the feedback somewhere in your HTML without making the user refresh.
you can achieve that behavior with a jquery function called $.get ... you can get more information on how to use here http://api.jquery.com/jQuery.get/
If you really want to (and I don't think you really do), you can use XMLHTTPRequest (wrapped in jQuery.get) to facilitate loading content into the page without page refreshing. You want an id or class on that tag, i.e. Click Me, and then:
<script>
$(".fetch").bind("click", function(evt)
{
$.get(this.attr("href"), function(data)
{
$("#whereIWantMyContent").html(data);
});
evt.preventDefault();
});
</script>
I would recommend you use AJAX to start with. A good place to being is http://www.w3schools.com/Ajax/Default.Asp
The link comes with a handy AJAX ASP/PHP Example too =))
Good Luck.

XHR call returns HTML, how to use that and reload the entire page?

A XHR call returns HTML, how do I tell the browser to use that and reload the entire page? I know the main use for XHR is to do partial page fresh but my case is a bit special. Thanks.
Or put it in a more general term, what is the best way to use JS to simulate a browser form GET request? window.location.replace("url")?
rather than trying to reload or something, have you considered doing something like
document.body.innerHTML = [the string HTML that you got back from XHR];
Or perhaps you could do it by building a new DOM from the HTML and then swapping it in?

Is there a way to AJAX load a page and change URL in URL bar without hashing?

This is probably going to get a resounding no, but I am wondering if it possible to have the URl change dynamically with using hashing, and without invoking a http request from the browser?
My client is keen on using AJAX for main navigation. This is fine, when the end user goes to the front page first, but when they want to use the deep linking, despite it working, it forces an extra load time as the page loads the front page, then invokes the AJAX from the hash.
UPDATE: Could it be possible, given that what I want to avoid is the page reload (the reason is that it looks bad) to stem the reload by catching the hash with PHP before the headers are sent, and redirecting before the page load. This way only one page loads, and the redirect is all but invisible to the user. Not sure how to do this, but seems like it is possible?
Yes, this is possible. I often do this to store state in the hash part of the URL. The result is that the page doesn't reload, but if the user does reload, they're taken to the right page.
Using this method, the URL will look like: "/index#page=home" or "/index#page=about"
You'll need to write a JavaScript function that handles navigation, and you'll need a containing div that gets rewritten with the contents fetched from AJAX.
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<div id="content"></div>
<script type="text/javascript">
function link(page) {
location.hash = "page="+page;
loadPage(page);
}
// NOTE: This is using MooTools. Use the AJAX method in whatever
// JavaScript framework you're using.
function loadPage(page) {
new Request.HTML({
url: "/ajax/"+page+".html",
onSuccess: function(tree, elements, html) {
document.id('content').setProperty('html', html);
}
}).get();
}
</script>
Now, you'll also need to have something that checks the hash on page load to load the right content initially. Again, this is using MooTools, but use whatever onLoad method your JavaScript framework provides.
<script type="text/javascript">
document.addEvent('domready', function() {
parts = location.hash.split('=');
loadPage(parts[1]);
}
</script>
Ok, the problem is that opening an AJAX link of the form http://example.com/#xyz results in a full page being downloaded to the browser, and then the AJAX-altered content is changed once the page has loaded and checked the hash part of its URL. The user has a diconcerting experience.
You can hugely improve this by making a page that just contains the static elements - menus, etc. - and a loading GIF in the content area. This page checks its URL upon loading and dynamically fetches the content specified by the hash part. The page can have any URL you want; we'll use http://example.com/a. Links to this page (http://example.com/a#xyz) now provide a good user experience for users with scripting enabled.
However, new users won't come to the site by fetching http://example.com/a; they'll fetch http://example.com. This is fine - serve the full page, including the home page content and links that don't require scripting to work (e.g., http://example.com/xyz). A script run on loading this page should alter the href of AJAXable links to their AJAX form (http://example.com/a#xyz); thus the first link a user clicks on will result in a full page load but subsequent ones won't.
The only remaining problem is is a no-script user gets sent an AJAX link. You can add a noscript block to the AJAX page that contains a message explaining the problem and provides a link back to the homepage; you could include instructions on how to enable scripting or even how to modify the link by removing a# and pressing enter.
It's not a great answer, but you can offer a different link in the page itself; e.g., if the address bar shows /#xyz you include a link to /xyz somewhere in the page. You could also add a link or button that uses script to bookmark the page, which would again use the non-AJAX form of the link.

How do I ensure AJAX still works after content moved from iFrame through DOM manipulation

After submitting an iFrame, content with AJAX enabled functions is returned and everything works.
Once I move the content out from the iFrame to the main page through DOM manipulation and remove the iFrame, AJAX stops working.
How can I make it work?
I grab the body content of the iFrame and move it to an outside element through .innerHTML
It really depends on the AJAX implementation...
Once you've grabbed the DOM nodes from the iFrame and placed them in your < body >, they are essentially new DOM nodes. Any events attached to them would need to be rebound and any code interacting with them would need to be re-executed.
Why not simply load the iFrame into the main page's DOM to begin with and execute the AJAX code there?

AJAX and iFrame: Calling AJAX from inside the iFrame to Update an Outside DIV

I have a page where a user can upload a file along with some other input. Because I wanted this to be AJAX-like, I resorted to using an iFrame to accomplish this.
After the file is uploaded and an iFrame is loaded with a response page, I need to update a DIV outside of the iFrame with an AJAX call. The reason for separate updates, is that the result of the outside DIV depends on the input that the user provided with the file input.
Can this be done? Am I approaching this the wrong way?
Thank you!
UPD: Can the returned client code from within the iFrame "see" elements outside that iFrame?
Write your code in the onload event of the page loaded into the iframe. Then top will give you the top frame or parent will give you the parent frame.
Yes , it can be done. But you can do away with,the need for an AJAX-call , to update the outside the div.
Have your, servlet(assuming you are using JSP/servlets) that accepts the mutlipart request(the servlet that accepts the upload), return the intended response (to be shown on the refreshed iFrame), and ALONG WITH IT, the necessary information from the file input. This way you have all the necessary details on the client, in one response. A simple javascript function can achieve , updating the outer div with the information from the file input.

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