Form The Win!

ftw.html

<script>
  function formRequest(method) {
    const action = event.target.action;
    event.preventDefault();
    fetch(action, { method, body: new FormData(event.target) })
      .then(res => res.redirected && (location.href = res.url));
  }
  const PUT = formRequest.bind(null, "PUT");
  const DELETE = formRequest.bind(null, "DELETE");
</script>

<form action="/">
  <input type="text" name="title" />
  <input type="submit" value="GET" />
</form>

<form action="/" method="POST">
  <input type="text" name="title" />
  <input type="submit" value="POST" />
</form>

<form action="/" onsubmit="PUT()">
  <input type="text" name="title" />
  <input type="submit" value="PUT" />
</form>

<form action="/id1" onsubmit="DELETE()">
  <input type="text" name="title" />
  <input type="submit" value="DELETE" />
</form>