Cannot get the value of an ArrayBuffer Object in Javascript

Question

I have an ArrayBuffer object that I need to be able to convert to String to JSON, but I can't get the value of the [Int8Array] out of the object, even though it is clearly there.

I've tried all variations on this, but they all return undefined

console.log(result);//Returns the array buffer
//Following methods all return undefined?
console.log(result["[[Int8Array]]"]);
console.log(result[[[Int8Array]]]);
console.log(result[[["Int8Array"]]]);
console.log(result[Int8Array]);
console.log(result["Int8Array"]);

How can I get all the Int8Array or UInt8Array values that are clearly available in the object?

You should be able to get the individual values using `console.log(result[0])` etc. — , Jan 17 '19 at 08:33
That did not work, also always returns undefined. The comment below is correct in that I needed to instantiate a new ArrayBuffer for the values. — Sven0567, Jan 17 '19 at 08:37

Endless · Answer 1 · 2020-11-23T10:49:12.583

8

You can use the textDecoder that accepts ArrayBuffer (as well as uint8array) without having to deal with Uint8array's:

var str = new TextDecoder().decode(arrayBuffer)
var json = JSON.parse(str)

if you want to get straight to json

var json = await new Response(arrayBuffer).json()

edited Nov 23 '20 at 10:49

answered Jan 17 '19 at 08:41

Endless

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score 7 · Accepted Answer · answered Jan 17 '19 at 08:35

You need to intiantiate a new Uint8Array to get their values, you can't access them directly using your ArrayBuffer instance.

var buf = new ArrayBuffer(8);
var int8view = new Uint8Array(buf);
console.log(int8view)

JSFiddle : https://jsfiddle.net/v8m7pjqb/

Cannot get the value of an ArrayBuffer Object in Javascript

2 Answers2