Request: arrayBuffer() method

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since March 2017.

Note: This feature is available in Web Workers.

The arrayBuffer() method of the Request interface reads the request body and returns it as a promise that resolves with an ArrayBuffer.

Syntax

arrayBuffer()

Parameters

None.

Return value

A promise that resolves with an ArrayBuffer.

Exceptions

TypeError

Thrown for one of the following reasons:

The request body is disturbed or locked.
There was an error decoding the body content (for example, because the Content-Encoding header is incorrect).

RangeError

Thrown if there is a problem creating the associated ArrayBuffer (for example, if the data size is too large).

Examples

js
const myArray = new Uint8Array(10);

const request = new Request("/myEndpoint", {
  method: "POST",
  body: myArray,
});

request.arrayBuffer().then((buffer) => {
  // do something with the buffer sent in the request
});

Specifications

Specification

Fetch
# ref-for-dom-body-arraybuffer①

Browser compatibility

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Fetch API
Request
Constructor
1. Request()
Instance properties
Instance methods
Related pages for Fetch API
Guides
1. Using the Fetch API
2. Using Deferred Fetch