“Отправка запроса AJAX перед отправкой формы.” Ответ

Отправка запроса AJAX перед отправкой формы.

$('form').submit(function(e) { 

     // this code prevents form from actually being submitted
     e.preventDefault();
     e.returnValue = false;

     // some validation code here: if valid, add podkres1 class

     if ($('input.podkres1').length > 0) { 
        // do nothing
     } else {

        var $form = $(this);

        // this is the important part. you want to submit
        // the form but only after the ajax call is completed
         $.ajax({ 
             type: 'post',
             url: someUrl, 
             context: $form, // context will be "this" in your handlers
             success: function() { // your success handler
             },
             error: function() { // your error handler
             },
             complete: function() { 
                // make sure that you are no longer handling the submit event; clear handler
                this.off('submit');
                // actually submit the form
                this.submit();
             }
         });
     }
});