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FormDataEvent: formData property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨September 2021⁩.

The formData read-only property of the FormDataEvent interface contains the FormData object representing the data contained in the form when the event was fired.

Value

A FormData object.

Examples

// grab reference to form

const formElem = document.querySelector("form");

// submit handler

formElem.addEventListener("submit", (e) => {
  // on form submission, prevent default
  e.preventDefault();

  // construct a FormData object, which fires the formdata event
  new FormData(formElem);
});

// formdata handler to retrieve data

formElem.addEventListener("formdata", (e) => {
  console.log("formdata fired");

  // Get the form data from the event object
  let data = e.formData;
  for (const value of data.values()) {
    console.log(value);
  }

  // submit the data via XHR
  const request = new XMLHttpRequest();
  request.open("POST", "/formHandler");
  request.send(data);
});

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Opera Safari Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet WebView Android WebView on iOS
formData 77 79 72 64 15 77 79 55 15 12.0 77 15

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/FormDataEvent/formData