access PHP Methods with jQuery - php

Question

I'm completely new to jQuery and Ajax, but I've managed to learn how to do the Hello World, populate a select tag, etc, etc...
Problem is, I don't like to use structural PHP. The way I learned I have to call some PHP file with $.getJSON and that file has to "echo" my result.
What I want is to be able to call a PHP file that is actually a class with some methods and the return of the method would be what JavaScript would receive instead of just an echo result.
Thanks for your attention.
Ps.: I have a lot of experience with PHP-OOP and Flex+PHP using Amfphp. I'm trying to build a different version of view and I would like to re-use the classes that Flex already use.

Answer 1

jQuery runs on your computer, and PHP runs on the server. PHP and jQuery can only communicate via a series of well-crafted strings. On the server, you are free to create objects, run methods, manipulate output, and anything else. However, if you're going to be feeding that data back into your jQuery application (still running on the client's machine), you'll need to echo (or output) the results of your PHP script.
You may consider something like this:
$.post('server.php', { 'class':'foo', 'method':'bar' }, function( response ) {
/* do something with the output of $foo->bar(); */
});
As you can see here, I can define the class and method I'd like to have called on the server. From server.php, we would look to $_POST['class'] and $_POST['method'] to determine what we will instantiate, and which methods we will run.

Answer 2

The AMF is somehow different from HTTP, they're different protocols.
When using AJAX (jQuery or not), you're calling HTTP methods on URIs, not OOP methods. So everything ends up in a minimum of two mappings:
Your application logic mapped to methods and URIs.
Your Javascript code mapped to methods and URIs.
Here is a sample using Respect\Rest:
$router->get('/users/*', function($userName) {
return MyDatabaseLayer::fetchUser($userName); //Illustrative
})->accept(
'application/json' => function($data) {
header('Content-type: application/json');
return json_encode($data);
}
);
Now the jQuery part:
$.getJSON('/users/alganet', function(user) {
alert(user.name);
});
You should use appropriate HTTP methods for different actions. Saving an user would be something like:
$router->post('/users/*', function($userName) {
return MyDatabaseLayer::saveUser($_POST['user']); //Illustrative
});
jQuery:
$.post('/users', $("$userform").serialize());
There are four main HTTP methods: GET, POST, PUT and DELETE. GET and POST are the most common ones.
There is a nice trivia: Both HTTP, REST and AMF were written by the same guy: Roy Fielding.