在此页

• 句法
• 范例
• 规范
• 浏览器兼容性
• 相关话题

草案
此页面不完整。

这是 实验性技术
检查 浏览器兼容性表格 要小心谨慎在生产中使用这之前。

desiredSize 只读特性在 WritableStreamDefaultWriter interface returns the desired size required to fill the stream's internal queue.

句法

var desiredSize = writableStreamDefaultWriter.desiredSize;
					

值

An integer. Note that this can be negative if the queue is over-full.

The value will be null if the stream cannot be successfully written to (due to either being errored, or having an abort queued up), and zero if the stream is closed.

异常

TypeError

The writer’s lock is released.

范例

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

规范	状态	注释
流 The definition of 'desiredSize' in that specification.	实时标准	初始定义。

浏览器兼容性

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request. 更新 GitHub 上的兼容性数据

	桌面						移动
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
desiredSize	Chrome 59	Edge 16	Firefox No	IE No	Opera 46	Safari ?	WebView Android 59	Chrome Android 59	Firefox Android No	Opera Android 43	Safari iOS ?	Samsung Internet Android 7.0

图例

完整支持

完整支持

不支持

不支持

兼容性未知 ?

兼容性未知

实验。期望将来行为有所改变。

实验。期望将来行为有所改变。

元数据

• 最后修改： Feb 16, 2020

相关话题

1. Streams API
2. WritableStreamDefaultWriter
3. 构造函数

   1. WritableStreamDefaultWriter()
4. 特性

   1. closed
   2. desiredSize
5. 方法

   1. abort()
   2. close()
   3. ready
   4. releaseLock()
   5. write()
6. Related pages for Streams

   1. Body.body
   2. ByteLengthQueuingStrategy
   3. CountQueuingStrategy
   4. ReadableByteStreamController
   5. ReadableStream
   6. ReadableStreamBYOBReader
   7. ReadableStreamBYOBRequest
   8. ReadableStreamDefaultController
   9. ReadableStreamDefaultReader
   10. WindowOrWorkerGlobalScope.fetch()
   11. WritableStream
   12. WritableStreamDefaultController