IdleDeadline.timeRemaining() - Web API 接口参考 编辑

这是一个实验中的功能
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The timeRemaining() method on the IdleDeadline interface returns the estimated number of milliseconds remaining in the current idle period. The callback can call this method at any time to determine how much time it can continue to work before it must return. For example, if the callback finishes a task and has another one to begin, it can call timeRemaining() to see if there's enough time to complete the next task. If there isn't, the callback can just return immediately, or look for other work to do with the remaining time.

By the time timeRemaining() reaches 0, it is suggested that the callback should return control to the user agent's event loop.

Syntax

timeRemaining = IdleDeadline.timeRemaining();

Return value

A DOMHighResTimeStamp value (which is a floating-point number) representing the number of milliseconds the user agent estimates are left in the current idle period. The value is ideally accurate to within about 5 microseconds.

If the IdleDeadline object's didTimeout property is true, this method returns zero.

Example

See our complete example in the article Cooperative Scheduling of Background Tasks API.

Specifications

Specification	Status	Comment
Cooperative Scheduling of Background Tasks	Proposed Recommendation

Browser compatibility

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The compatibility table in 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.

See also

• Collaborative Scheduling of Background Tasks
• IdleDeadline
• Window.requestIdleCallback()
• Window.cancelIdleCallback()