AJAX post from View to Controller in Block - how does the route controller work?

I haven't quite found the code that takes yourpage.php/block_controller/bID i.e the url generated by
<?php echo $view->action("do_something");?>
and directs it to the correct function of the blocks controller.

I'm assuming it takes the second parameter, uses this to find the block id, and then uses the first parameter to know which method to call. I also assume this route is handled differently from the GET routes, else a method called sale() and a page called sale would conflict. I had a little look in src/Routing and the bootstrap files, but I couldn't find anything that could help me understand why the ajax request below is not working.

For clarity, it does not work with the post method on a standard php form either
<form action="<?php echo $view->action("do_something");?>" method="post">
<input name="item" type="text"/>
                        <button type="submit">submit</button>

If anyone can help me understand this better, (or even just point out my typo!) that would be great. Thanks

public function do_something($bID = false)
   echo 'this is the response';

            type        : 'POST', // define the type of HTTP verb we want to use (POST for our form)
            url         : '<?php echo $view->action("do_something");?>',
            data        : formData, // our data object
            dataType    : 'json', // what type of data do we expect back from the server
            encode          : true
        .done(function(data) {

View Replies:
WillemAnchor replied on at Permalink Reply
in the controller use action_ prefix

public function action_do_something($bID = false)
echo 'this is the response';

in view.php you can use $this->action("do_something")