This feature is well established and works across many devices and browser versions. It’s been available across browsers since May 2022.
Note: This feature is available in Web Workers.
The locked read-only property of the WritableStream interface returns a boolean indicating whether the WritableStream is locked to a writer.
A boolean value indicating whether or not the writable stream is locked.
const writableStream = new WritableStream(
{
write(chunk) {
// …
},
close() {
// …
},
abort(err) {
// …
},
},
queuingStrategy,
);
// …
const writer = writableStream.getWriter();
writableStream.locked;
// should return true, as the stream has been locked to a writer
| Specification |
|---|
| Streams> # ref-for-ws-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 |
59 | 16 | 100 | 47 | 14.1 | 59 | 100 | 44 | 14.5 | 7.0 | 59 | 14.5 |
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https://developer.mozilla.org/en-US/docs/Web/API/WritableStream/locked