I have a script the processes about 100 rows of data within a foreach loop. I would like to have a page that has a submit button and as the script successfully iterates it would append data from that row to a div on the page- giving some feedback to the user. It's different than most of the examples Im seeing online in that the php script would be posting multiple times instead just once. thanks for any input
Due to the nature of HTTP, your best bet might be to use Ajax.
My thoughts would be to send an Ajax request to your script, and then once the script is done and sends the response, parse the response and put it into your div.
Make 2 calls to php from jQuery
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In a nutshell.... what i want to do is a install script for my website... but i want everything to be done in 1 page which will connect to another php file that will have all the server side processing code. In order to do that i use JQuery, Ajax & PHP...
Now my question lies in what are the best practices in order to do that. How do I make my server side PHP script to take multiple user inputs that will happen throughout a lengthy installation processes?
I was thinking on using switch statements that will trigger classes & functions and like that being able to access multiple processes (Classes and functions) that will be stored in the same file?... or people normally use other things?? never done this before and couldnt find a straight forward tutorial for it on how is best to design it.
I was thinking on maybe being able to access classes through AJAX in php but that doesn't seem to be possible.... can i trigger functions from AJAX in php?
I really appreciate the help in how normally this is approached
thx
It would be too lengthy to define the whole process in SO in detail. But the basic idea is:
User fills in form clicks NEXT button.
You get all the form values (in JavaScript), post it to a PHP page using AJAX
The PHP page gives you back a flag (SUCCESS/ERROR) [In the background, if it is success, PHP has persisted the data into a database]
If JavaScript receives ERROR, you show user the error message and ask him to correct the form
If java script receives SUCCESS, you call the next PHP script, which generates the next form and sends it to your JavaScript
JavaScript populates this form content within a DIV in your page, effectively wiping out the current form and showing the new form in its place.
..and the whole process restarts from the first step once again for the new form..
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.
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();}
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.
Currently I'm doing this in two steps:
1.post it to ask.php
2.after inserting it into database,use header("REFRESH: 0;URL=post.html") to jump to the result page
But how to do it all in one step,say,like SO here?
SO does it using Ajax. But for the easier win, why not just use header('Location: http://example.com/post.html') instead of a refresh?
It happens using ajax, I'm guessing.
-User types post, hits submit.
-Post content is sent via ajax to the server where it tries to save it.
-If it is saved:
The post is added to the page using javascript and some pretty animations and all the various listeners are added to the clickable elements.
-If not:
Show some error.
I'm sure there's more to it than that, but that's probably the basic idea.
Instead of a that refresh header, after processing the POST request, tell the client to view the result with a Location redirection header
header("Location: http://www.example.com/post/$post_id");
That kind of thing is done with Ajax. Using javascript to request small(er) amounts of data from the server, then updating the page, bypassing a full page request/refresh.
Here's a few libraries that may help get you started with Ajax and PHP:
XAJAX
Zend_Json_Server (more complex)
PHP Ajax Example at W3Schools