serializeArray from to array. via https://plainjs.com/javascript/ajax/serialize-form-data-into-an-array-46/

serialize.js

function serialize(form) {
    var field, l, s = [];
    if (typeof form == 'object' && form.nodeName == "FORM") {
        var len = form.elements.length;
        for (var i=0; i<len; i++) {
            field = form.elements[i];
            if (field.name && !field.disabled && field.type != 'file' && field.type != 'reset' && field.type != 'submit' && field.type != 'button') {
                if (field.type == 'select-multiple') {
                    l = form.elements[i].options.length; 
                    for (var j=0; j<l; j++) {
                        if(field.options[j].selected)
                            s[s.length] = encodeURIComponent(field.name) + "=" + encodeURIComponent(field.options[j].value);
                    }
                } else if ((field.type != 'checkbox' && field.type != 'radio') || field.checked) {
                    s[s.length] = encodeURIComponent(field.name) + "=" + encodeURIComponent(field.value);
                }
            }
        }
    }
    return s.join('&').replace(/%20/g, '+');
}

serializeArray.js

function serializeArray(form) {
    var field, l, s = [];
    if (typeof form == 'object' && form.nodeName == "FORM") {
        var len = form.elements.length;
        for (i=0; i<len; i++) {
            field = form.elements[i];
            if (field.name && !field.disabled && field.type != 'file' && field.type != 'reset' && field.type != 'submit' && field.type != 'button') {
                if (field.type == 'select-multiple') {
                    l = form.elements[i].options.length; 
                    for (j=0; j<l; j++) {
                        if(field.options[j].selected)
                            s[s.length] = { name: field.name, value: field.options[j].value };
                    }
                } else if ((field.type != 'checkbox' && field.type != 'radio') || field.checked) {
                    s[s.length] = { name: field.name, value: field.value };
                }
            }
        }
    }
    return s;
}

serializeArray1.js

// via zeptojs

var serializeArray = function(form) {
    var name, type, result = [],
      add = function(value) {
        if (value.forEach) return value.forEach(add)
        result.push({ name: name, value: value })
      }
    if (typeof form == 'object' && form.nodeName == 'FORM') {
      [].forEach.call(form.elements, function(field){
        type = field.type, name = field.name
        if (name && field.nodeName.toLowerCase() != 'fieldset' &&
          !field.disabled && type != 'submit' && type != 'reset' && type != 'button' && type != 'file' &&
          ((type != 'radio' && type != 'checkbox') || field.checked))
            add(field.value)
      })
    }
    return result
  }

serializeJSON.js

  serializeJSON = function(form) {
    var json = {};

    [].forEach.call(form.querySelectorAll('input,select,textarea'), function(field) {
      var el = field,
        key = el.name,
        val = el.value;

      var validElem = val != '' && val !== undefined && val !== null && el.hasAttribute('name') && !el.disabled;

      if (validElem) {
        if (el.hasAttribute('type') && el.getAttribute('type').toLowerCase() == 'checkbox') {
          el.checked && ( (Object.prototype.toString.call(json[key]) == '[object Array]' ) ? json[key].push(val) : json[key] = [val]);
        } else if (el.hasAttribute('type') && el.getAttribute('type').toLowerCase() == 'radio') {
          el.checked && (json[key] = val);
        } else {
          json[key] = val;
        }
      }
    });

    return json;
  };