DataView.prototype.byteLength

The byteLength accessor property represents the length (in bytes) of the dataview.

Description

The byteLength property is an accessor property whose set accessor function is undefined, meaning that you can only read this property. The value is established when an DataView is constructed and cannot be changed. If the DataView is not specifying an offset or a byteLength, the byteLength of the referenced ArrayBuffer or SharedArrayBuffer will be returned.

Examples

Using the byteLength property

var buffer = new ArrayBuffer(8);
var dataview = new DataView(buffer);
dataview.byteLength; // 8 (matches the byteLength of the buffer)

var dataview2 = new DataView(buffer, 1, 5);
dataview2.byteLength; // 5 (as specified when constructing the DataView)

var dataview3 = new DataView(buffer, 2);
dataview3.byteLength; // 6 (due to the offset of the constructed DataView)

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
byteLength
9
12
15
10
12.1
5.1
4
18
15
12.1
5
1.0

See also

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https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView/byteLength