WritableStreamDefaultWriter.desiredSize
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since June 2022.
WritableStreamDefaultWriter 接口的只读属性 desiredSize 返回填充满流的内部队列需要的大小。
值
一个整数。请注意，在队列已满的情况下，则可能是负数。
如果无法成功写入流（由于流发生错误或者中止入队），则该值为 null，如果流关闭，则该值为 0。
异常
TypeError-
writer 的锁已被释放。
示例
js
const writableStream = new WritableStream({
write(chunk) {
...
},
close() {
...
},
abort(err) {
...
}
}, queuingStrategy);
...
const writer = writableStream.getWriter();
...
// return stream's desired size
let size = writer.desiredSize;
规范
| Specification |
|---|
| Streams # ref-for-default-writer-desired-size⑥ |