Defers invoking a function until the current call stack has cleared.
- Use
setTimeout()
with a timeout of1
ms to add a new event to the event queue and allow the rendering engine to complete its work. - Use the spread (
...
) operator to supply the function with an arbitrary number of arguments.
代码实现
const defer = (fn, ...args) => setTimeout(fn, 1, ...args);
// Example A:
defer(console.log, 'a'), console.log('b'); // logs 'b' then 'a'
// Example B:
document.querySelector('#someElement').innerHTML = 'Hello';
longRunningFunction();
// Browser will not update the HTML until this has finished
defer(longRunningFunction);
// Browser will update the HTML then run the function