Is there a way to trigger a function when a $_POST is received?
I have a php page that finishes executing and calls another page. The other page performs certain actions and POST updates back to this page. I need to be able to update a div as and when a POST is received.
Making an ajax request and using "success" callback as a trigger doesn't work since this will update my div ONLY ONCE. The problem is that this page will receive POST multiple times at irregular intervals and I need a way to trigger an action whenever POST is received.
Use Ajax (I'd use jQuery) and set a time interval to check if there was a status change. The "other page" should not post back to the first page, but save data in a "requestable" area (might be an database, a file etc) where this new info/status will be stored and retrieved periodically by the Ajax request.
Use AJAX, because you can't trigger $_POST recieving in php,
As I understand you just need to update some <div> inner html after post is recieved, and you are able to do it with jQuery events
I would do this in the following way (below is the PHP code, just FYI):
if (!empty($_POST)) {
// do whatever you mean by 'updating the div'
}
However AJAX may be more appropriate and it is (believe or not) more flexible.
AJAX call will be smaller load on your server and can update the box single or multiple times (depending on how you write the JS code) - in such case I recommend using jQuery for simplicity (if you are not familiar with JS).
usually, I would do something like this...
$var_posted=0;
if($_POST['var']){$var_posted=1;}
then...
if($var_posted==1){some_function();}
Related
I have a page that uses ajax to show users their current assignments. Instead of having to refresh the page to see if there are any updates, I'm using ajax to update the data every 4 seconds. It's been requested that I change the document title to show something like "Number of Tasks: 4" and have that update as well when the user either completes a new task, or gets assigned another one. I tried using a simple "setInterval" javascript function, but since PHP is server side, the variable piece doesn't update...
I've also tried setting "document.title" from within the ajax code, but that just plain didn't work.
Is there a simple way to update the document title to show the number of tasks assigned to the user viewing the page?
Return the value from the $_SESSION in the data sent with the AJAX response to the client Javascript code. Once you have it on the client side set whatever you need to it with javascript.
You'd have to call with ajax a php dedicated to return you only the number of tasks (and other information you may want).
To change the title you can just call document.title = "the data returned in ajax";.
And put all this code (ajax call and title set) inside a function with setinterval as you mentioned.
I have a page which shows a list of items. Page coded with html, css, php and using mysql db.
On that page a user can request to add one of the items to their special list.
I want to do this within the page without having to do a complete page refresh. So user clicks button to add, item is added to their list and button changed so they can't add it again.
Do I use ajax calls to run code behind the page and then refresh the div?
Or is there a better more efficient way to do it.
I'd prefer a php option of possible in case user has js turned off, but don't know if it can be done with using js.
Any help appreciated.
If you want dynamic content (changing the page without refreshing) you are going to have to use Javascript. To do what you are asking, you could call a PHP script via Ajax that outputs the contents of the div with the new item, and then change the div based on that response.
Dagon is exactly right. Create a form which handles the request and set the action of the form to the PHP script you want to handle the request. Note that although this can be the same php script that you use to process your ajax request, it does not necessarily have to be.
Many times when I implement such functionality, I'll set the PHP to send variables as POST (in the event of JS disabled) and have my ajax request as a GET so I can use a single PHP page to handle the 'same' request. When using AJAX, I'll have the script echo a specific code then have the ajax response handle that return.
if(val == 'OK') {
//in event of success, perhaps you want to hide the original form and show a success message
} else {
//do something like unhide a hidden div to display an error
}
If JavaScript is turned off, the page has to be reloaded. In your case jQuery could be very handy and simply rewrite the element you need to rewrite. The server send's a simple json. Using a PHP Framework might also be a good idea, since the way you ask it seems (with respect, and not wanting to offend), that you are not using any framework and might run into falls making your script vulnerable (sql injections for example)
If your visitor doesn't have JavaScript enabled and you want to serve anyways, then you have to do a page reload. First check if that is worth to do, who is your client/visitor, what browser do they use, ... questions like that help you to design your page/app.
I have a PHP page with a mysql connection, a select query and then i'm building a table using PHP. If i wanted to use jQuery AJAX to refresh the data on a setInterval, on the same page, how would i go about doing that? (by the way i can do it to another PHP page but i've never done it if the PHP stuff is on the same page)
If you want to keep making ajax calls i suggest you do long polling, which basically means you have a script that is requesting content via ajax every given time, and it will verify every time if the content has been modified, if not it will wait again and make another call.
I used jQuery Periodical updater for a chat box and it worked perfectly.
If you wnat to learn more about how jQuery and AJAX work, check out this Nettus article
You set the param in request, for instance file.php?ajax=1
The, depending on its value, you render full html or just the necessary elements for ajax
in php:
if($_GET['ajax']) renderAjax();
else renderFullHTML();
in js:
$.get('file.php?ajax=1', function(data) {
$('.result').html(data);
});
can any one please help how to get the values from the javascript to php other than while using submit button.
scenario:
i am searching for record, if the record found then, i need confrim alert asking to continue or not, if he click continue how can i say he selected continue
If you want to check without having a page reload, you probably want to execute an AJAX call, then depending on the result returned by the underlying PHP script, take the appropriate action. If you have no knowldege of how to implement this, take a look here
You can never use JavaScript to communicate with the page while it is loading, you can only send a new request to the web server from the JavaScript layer... although you can send that request to the same script that's already running, it will still be a new instance of the PHP script, just like when you open a new browser tab to the same page.
The only way for JavaScript to communicate with PHP at all, is by sending an HTTP request. But you don't have to refresh the page in order to do that if you use AJAX.
AJAX is basically a word to describe JavaScript exchanging information with web pages without refreshing the page. But note that it will still not be able to change variables in the PHP script which is running when the JavaScript code is executed.
In the case of PHP, I've used the open-source library SAJAX which is quite simple. You will find it at http://www.modernmethod.com/sajax/
Hope it helps and good luck!
You can use this as an example using jquery and PHP:
$.post('searchimage.php', { action: 'searchimage', imgreference: $(this).val() },
function(data) {imgsample.html(data);}
);
Basically apply the above function in a document ready function so its run when the page loads.
This can be triggered using $("#prodcode").click() or what ever event handler you want to use.
The php page in my example will get sent the value from imgreference as a post, you can do whatever you want in the php page then return the value which gets added to the imgsample (in this case a td)
hope this helps.
I have a run.php that has a button on it called "Run". Clicking it does a jQuery $.get() AJAX call back to a response.php on the server, and sends the result to a Javascript callback function getResponse(sData) inside run.php's HTML for display back on the browser. I want to have things such that as response.php runs through a list of tasks, it echoes a response back with the echo command and for getResponse to update a DIV with that status as it moves along. So, let's say I have 5 steps inside response.php, and therefore 5 echo statements back to getResponse().
I tried to get this to work, but what happens is that jQuery waits and then sends one single response all at once, rather than sending as it goes along with the 5 responses.
What's the technique?
The reason I ask is that I have a script that does something to a bunch of files. The first thing it does is a file count, so it updates my progress bar. Then, as it runs through files, it needs to increment my progress bar like every 1000 files.
I think there's no way to make that ajax call to have multiple response in just one call... but what I could suggest is you make a session on php... and in every steps on your tasks function, update that session... then make another ajax call that checks that session if any updates happened... if there is update then do what you have to do....
As you can't really get progress with xmlhttprequest, I suggest you can look into other ways of doing AJAX calls. One of them is through iframe. You can create hidden iframe, set it's sources to request.php and then periodically just check it's content. It should be possible since it's all it the same domain and restrictions does not apply.
iframe might work because it's not that different from normal browser window, meaning that it periodically applies data it gets into DOM even if request hasn't been finished yet. There's potentially might be problems with how different browsers do that, i.e. IE shows new content only if it got more than 4K or something. But it is possible to overcome that, I'm sure.
So, create new hidden iframe, add src attibute to your php script, make that script periodically write something to the client and on the client check what have been written and convert it to shiny GUI stuff.