const form = document.createElement("form");
form.innerHTML = `
  <input name="username" placeholder="Username" value="alice">
  <input name="age" type="number" value="25">
  <label><input type="checkbox" name="subscribe" checked> Subscribe</label>
  <button type="submit">Send</button>
`;
document.body.appendChild(form);

form.addEventListener("submit", (e) => {
  e.preventDefault();
  const data = new FormData(form);

  // Iterate entries
  for (const [key, value] of data.entries()) {
    console.log(key, "=", value);
  }

  // Convert to plain object
  const obj = Object.fromEntries(data);
  console.log("As object:", obj);
});