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 locked read-only property of the ReadableStream interface returns whether or not the readable stream is locked to a reader.
A readable stream can have at most one active reader at a time, and is locked to that reader until it is released. A reader might be obtained using ReadableStream.getReader() and released using the reader's releaseLock() method.
A boolean value indicating whether or not the readable stream is locked.
const stream = new ReadableStream({
// …
});
const reader = stream.getReader();
stream.locked;
// should return true, as the stream has been locked to a reader
| Specification |
|---|
| Streams> # ref-for-rs-locked②> |
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
locked |
52 | 14 | 65 | 39 | 10.1 | 52 | 65 | 41 | 10.3 | 6.0 | 52 | 10.3 |
ReadableStream() constructor
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https://developer.mozilla.org/en-US/docs/Web/API/ReadableStream/locked