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Response: formData() method

Baseline Widely available

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

Note: This feature is available in Web Workers.

The formData() method of the Response interface takes a Response stream and reads it to completion. It returns a promise that resolves with a FormData object.

Note: This is mainly relevant to service workers. If a user submits a form and a service worker intercepts the request, you could for example call formData() on it to obtain a key-value map, modify some fields, then send the form onwards to the server (or use it locally).

Syntax

formData()

Parameters

None.

Return value

A Promise that resolves with a FormData object.

Exceptions

AbortError DOMException

The request was aborted.

TypeError

Thrown for one of the following reasons:

The response body is disturbed or locked.
There was an error decoding the body content (for example, because the Content-Encoding header is incorrect).
The MIME type of the body cannot be determined from the Content-Type headers included in the response.
The body cannot be parsed as a FormData object.

Examples

TBD.

Specifications

Specification
Fetch> # ref-for-dom-body-formdata①>

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`	60	79	39	47	14.1 10.1–14.1 The method exists but always rejects with `NotSupportedError`. See bug 215671.	60	39	44	14.5 10.3–14.5 The method exists but always rejects with `NotSupportedError`. See bug 215671.	8.0	60	14.5 10.3–14.5 The method exists but always rejects with `NotSupportedError`. See bug 215671.