What is the best way to implement the mechanism for saving data from a large form?

Question

Kohana

When editing a large form, the user sends a POST to the server. If the form is filled out incorrectly, I make a redirect indicating a filling error, while the data may be resent.
But after redirecting the form, the data is lost. How to make the user's form data remain after filling in and return filling errors to him?
Throw it all into local storage? or fill out the form according to the data previously filled in by the user?

Answer 1

2017 is in the yard! Use ajax!

Answer 2

$(document).ready(function(){
      $("идентефикатор_кнопки_для_отправки_данных_формы").click(function() {
        //собераем все данные из формы
         var form_data = new FormData("идентификатор_формы");
            $.ajax({
            type: "POST", //Метод отправки
            url: "путь_до_файла",
            data: form_data,
            success: function() {
                        
            },
            error:function(){

            },
        });
    });
   });

Sending form data with ajax. On the server, we check the validity of the data and return the response. Depending on the answer, we either display an error or reset the form fields, depending on what you need.