Sparksss

// This is function which send data
// In this variant, we need invoke preventDefault() function
// in first line code our function.
const sendData = (event) => {
  event.preventDefault(); // this line need for cancel default behavior and send via ajax
  // take our form
  const form = event.target;
  // create object for parsing to json
  const data = {};
  // add data, from form

Sparksss

// This works on all devices/browsers, and uses IndexedDBShim as a final fallback 
var indexedDB = window.indexedDB || window.mozIndexedDB || window.webkitIndexedDB || window.msIndexedDB || window.shimIndexedDB;

// Open (or create) the database
var open = indexedDB.open("MyDatabase", 1);

// Create the schema
open.onupgradeneeded = function() {
    var db = open.result;
    var store = db.createObjectStore("MyObjectStore", {keyPath: "id"});