IdleDeadline.timeRemaining()
Experimental: 这是一个实验中的功能
此功能某些浏览器尚在开发中，请参考浏览器兼容性表格以得到在不同浏览器中适合使用的前缀。由于该功能对应的标准文档可能被重新修订，所以在未来版本的浏览器中该功能的语法和行为可能随之改变。
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 (en-US) property is true, this method returns zero.
Example
See our complete example in the article Cooperative Scheduling of Background Tasks API.
Specifications
| Specification |
|---|
| requestIdleCallback() Cooperative Scheduling of Background Tasks # dom-idledeadline-timeremaining |
Browser compatibility
BCD tables only load in the browser