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                <form id="myform" action="get">
    <legend>Example form</legend>
    <div class="formgrid">
      <input id="name" name="name" type="text" />
      <label for="name">name</label>
      <input id="email" name="email" type="email" />
      <label for="email">email</label>
      <textarea id="comments" name="comments" rows="5" cols="20"></textarea>
      <label for="comments">comments</label>
      <button type="submit">SUBMIT</button>


                * {
  font-family: sans-serif;
  font-size: 1em;

body {
  color: #111;
  background-color: #eee;

body, input, textarea, select, option, button, label {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Roboto", "Oxygen", "Ubuntu", "Droid Sans", "Helvetica Neue", sans-serif;
  font-size: 100%;

p {
  max-width: 40em;
  margin: 1em auto;

fieldset {
  max-width: 40em;
  padding: 4px;
  margin: 2em auto;
  border: 0 none;

legend {
  font-size: 1.2em;
  width: 100%;
  margin-bottom: 0.5em;
  border-bottom: 1px dotted #99c;

input, output, textarea, select, button {
  box-sizing: border-box;
  padding: 0.2em 0.4em;
  margin: 0.2em 0;
  outline: 0 none;
  border: 0 none;
  box-shadow: none;

button {
  max-width: 9em;
  padding: 0.2em 2em;
  background-color: #ddd;
  box-shadow: 0 2px 0 #bbb;
  cursor: pointer;

label {
  width: auto;
  text-align: right;
  box-sizing: border-box;
  user-select: none;
  cursor: pointer;

input:focus + label, textarea:focus + label, select:focus + label {
  font-weight: bold;

.formgrid {
  display: grid;
  grid-template-columns: 1fr 1em 2fr;
  grid-gap: 0.3em 0.6em;
  grid-auto-flow: dense;
  align-items: center;

input, output, textarea, select, button {
  grid-column: 2 / 4;
  width: auto;
  margin: 0;

textarea + label {
  align-self: start;


                // form binding class
class FormBind {
  #Field = {};
  constructor(form) {
    // initialize object properties
    const elements = form.elements;
    for (let f = 1; f < elements.length; f++) {
      const field = elements[f], name =;
      if (name) {
        this[name] = field.value;
        this.#Field[name] = field;

    // form change events
    form.addEventListener('input', e => {
      const name =;
      if (this.#Field[ name ]) {
        this[ name ] = this.#Field[ name ].value;
  // update property and field
  updateValue(property, newValue) {
    if (this.#Field[ property ]) {
      this[property] = newValue;
      this.#Field[property].value = newValue;
      return true;
    return false;

// form proxy traps
const FormProxy = {

  // intercept set
  set(target, property, newValue) {
    return target.updateValue(property, newValue);

// form 2-way data binder
function FormBinder(form) {
  return form ? new Proxy(new FormBind(form), FormProxy) : undefined;

// form reference
const myformElement = document.getElementById('myform');

// prevent submit and show current properties
myformElement.addEventListener('submit', e => {

// create 2-way data form
const myForm = FormBinder(myformElement); = "Some Name"; = '';
myForm.comments = 'no comment';

// show form properties
function showProperties(obj) {
  console.log('Current values:');
  for (const p in obj) {
    console.log(`${ p }: ${ obj[ p ] }`)