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FileReader: readAsArrayBuffer() method

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨July 2015⁩.

Note: This feature is available in Web Workers.

The readAsArrayBuffer() method of the FileReader interface is used to start reading the contents of a specified Blob or File. When the read operation is finished, the readyState property becomes DONE, and the loadend event is triggered. At that time, the result property contains an ArrayBuffer representing the file's data.

Note: The Blob.arrayBuffer() method is a newer promise-based API to read a file as an array buffer.

Syntax

readAsArrayBuffer(blob)

Parameters

blob

The Blob or File from which to read.

Return value

None (undefined).

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
readAsArrayBuffer 6 12 3.6 12 6 18 32 12 6 1.0 3 6

See also

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https://developer.mozilla.org/en-US/docs/Web/API/FileReader/readAsArrayBuffer