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ByteLengthQueuingStrategy: size() method

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨January 2019⁩.

Note: This feature is available in Web Workers.

The size() method of the ByteLengthQueuingStrategy interface returns the given chunk's byteLength property.

Syntax

size(chunk)

Parameters

chunk

A chunk of data being passed through the stream.

Return value

An integer representing the byte length of the given chunk.

Examples

const queuingStrategy = new ByteLengthQueuingStrategy({ highWaterMark: 1 });

const readableStream = new ReadableStream(
  {
    start(controller) {
      // …
    },
    pull(controller) {
      // …
    },
    cancel(err) {
      console.log("stream error:", err);
    },
  },
  queuingStrategy,
);

const size = queueingStrategy.size(chunk);

Specifications

Specification
Streams>
# blqs-size>

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
size 52 16 65 39 10.1 52 65 41 10.3 6.0 52 10.3

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/ByteLengthQueuingStrategy/size