jQuery serializeObject

jquery-serializeobject.js

function convertArrayObjectsToArrays (obj) {
  return (function _traverse (obj) {
    if (Object.prototype.toString.call(obj) === '[object Array]') {
      return obj.map(el => _traverse(el));
    }

    else if (obj && Object.prototype.toString.call(obj) === '[object Object]') {
      const keys = Object.keys(obj);

      if (!keys.length || keys.find(key => !/\d/.test(key))) {
        for (const key in obj) {
          if (obj.hasOwnProperty(key)) obj[key] = _traverse(obj[key]);
        }

        return obj;
      } else {
        return Object.entries(obj).reduce((prev, [ key, value ]) => {
          prev[key] = _traverse(value);
          return prev;
        }, []);
      }
    }

    else return obj;
  })(obj);
}

$.fn.serializeObject = function () {
  const obj =  $(this).serializeArray().reduce((prev, { name, value }) => {
    const names = name.match(/(?<=\[).*?(?=\])/g) || [];
    names.unshift.apply(names, name.match(/^[^\[]+/g) || []);
    if (!names.length) return prev;

    names.reduce((prev, name, i) => {
      if (name === '') {
        const index = Object.keys(prev).filter(key => /\d/.test(key));
        name = index.length ? Math.max(index) + 1 : 0;
      }

      prev[name] = names.length - 1 === i ? value : (prev[name] || {});
      return prev[name];
    }, prev);

    return prev;
  }, {});

  return convertArrayObjectsToArrays(obj);
}