Function persist

form-persistence.js:34–58

* Registers the given form for persistence by saving its data to local or session storage. * Saved form data will be stored upon page refresh and cleared upon form submission. * Saved form data will be loaded upon calling this function, typically on page load. * * @param {HTMLFo

(form, options)

     *                    is excluded if the function returns true.
     */
    function persist(form, options) {
        let defaults = {
            saveOnSubmit: false
        }
        let config = Object.assign({}, defaults, options)
        load(form, config)
        // Some devices like ios safari do not support beforeunload events.
        // Unload event does not work in some situations, so we use both unload/beforeunload
        // and remove the unload event if the beforeunload event fires successfully.
        // If problems persist, we can add listeners on the pagehide event as well.
        let saveForm = () => save(form, config)
        let saveFormBeforeUnload = () => {
            window.removeEventListener('unload', saveForm)
            saveForm()
        }
        window.addEventListener('beforeunload', saveFormBeforeUnload)
        window.addEventListener('unload', saveForm)
        if (!config.saveOnSubmit) {
            form.addEventListener('submit', () => {
                window.removeEventListener('beforeunload', saveFormBeforeUnload)
                window.removeEventListener('unload', saveForm)
                clearStorage(form, config)
            })
        }
    }

    /**
     * Serializes the given form into an object, excluding password and file inputs.