The HTMLFormElement property elements returns an HTMLFormControlsCollection listing all the form controls contained in the <form> element.

Independently, you can obtain just the number of form controls using the length property.

You can access a particular form control in the returned collection by using either an index or the element's name or id attributes.

Prior to HTML 5, the returned object was an HTMLCollection, on which HTMLFormControlsCollection is based.

An HTMLFormControlsCollection containing all non-image controls in the form. This is a live collection; if form controls are added to or removed from the form, this collection will update to reflect the change.

The form controls in the returned collection are in the same order in which they appear in the form by following a preorder, depth-first traversal of the tree. This is called tree order.

Only the following elements are returned:

• <button>
• <fieldset>
• <input> (with the exception that any whose type is "image" are omitted for historical reasons)
• <object>
• <output>
• <select>
• <textarea>

In this example, we see how to obtain the list of form controls as well as how to access its members by index and by name or ID.

<form id="my-form">
  <label>
    Username:
    <input type="text" name="username" />
  </label>
  <label>
    Full name:
    <input type="text" name="full-name" />
  </label>
  <label>
    Password:
    <input type="password" name="password" />
  </label>
</form>

const inputs = document.getElementById("my-form").elements;
const inputByIndex = inputs[0];
const inputByName = inputs["username"];

This example gets the form's element list, then iterates over the list, looking for <input> elements of type "text" so that some form of processing can be performed on them.

const inputs = document.getElementById("my-form").elements;

// Iterate over the form controls
for (let i = 0; i < inputs.length; i++) {
  if (inputs[i].nodeName === "INPUT" && inputs[i].type === "text") {
    // Update text input
    inputs[i].value.toLocaleUpperCase();
  }
}