@kcuf-hook/use-debounced/dist/esm/hook/use-debounced-callback.js

React hook - useDebounced/useThrottled.

import _toConsumableArray from "@babel/runtime/helpers/toConsumableArray";
import { useRef, useMemo, useEffect } from 'react';
import useIsUnmounted from '@kcuf-hook/use-is-unmounted';
import { resolveOptions } from '../util';
export default function useDebouncedCallback(fn, options) {
  var refFn = useRef(fn);
  var refArgs = useRef(null); // 上次调用 `fn` 的参数列表，执行后会被清空
  var refTimeCalled = useRef(0); // 上次调用 `fn` 的时间（但不一定执行）
  var refTimeInvoked = useRef(0); // 上次真正执行 `fn` 的时间
  var refTimerId = useRef(null);
  var isUnmounted = useIsUnmounted();
  var _resolveOptions = resolveOptions(options),
    delay = _resolveOptions.delay,
    delayMax = _resolveOptions.delayMax,
    immediate = _resolveOptions.immediate;
  refFn.current = fn; // always fresh

  useEffect(function () {
    return function () {
      if (refTimerId.current) {
        clearTimeout(refTimerId.current);
      }
      refTimerId.current = null;
    };
  }, []);
  return useMemo(function () {
    function invokeFn() {
      var args = refArgs.current;
      if (args) {
        refArgs.current = null;
        refTimeInvoked.current = Date.now();
        refFn.current.apply(refFn, _toConsumableArray(args));
      }
    }
    function startTimer(pendingFunc, wait) {
      if (refTimerId.current) {
        clearTimeout(refTimerId.current);
      }
      refTimerId.current = setTimeout(pendingFunc, wait);
    }
    function timerExpired() {
      if (isUnmounted()) {
        return;
      }
      if (Date.now() - refTimeCalled.current >= delay) {
        refTimerId.current = null;
        invokeFn();
        return;
      }
      var time = Date.now();
      var timeSinceLastCall = time - refTimeCalled.current;
      var timeSinceLastInvoke = time - refTimeInvoked.current;
      var timeWaiting = delay - timeSinceLastCall;
      var remainingWait = delayMax >= delay ? Math.min(timeWaiting, delayMax - timeSinceLastInvoke) : timeWaiting;
      startTimer(timerExpired, remainingWait);
    }
    function callFn() {
      var time = Date.now();
      for (var _len = arguments.length, args = new Array(_len), _key = 0; _key < _len; _key++) {
        args[_key] = arguments[_key];
      }
      refArgs.current = args;
      refTimeCalled.current = time;
      if (immediate && !refTimerId.current) {
        invokeFn();
      }
      if (delayMax >= delay && time - refTimeInvoked.current >= delayMax) {
        invokeFn();
        startTimer(timerExpired, delay);
      }
      if (!refTimerId.current) {
        startTimer(timerExpired, delay);
      }
    }
    return callFn;
  }, [delay, delayMax, immediate, isUnmounted]);
}
//# sourceMappingURL=use-debounced-callback.js.map