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bytesforce-form-render

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通过 JSON Schema 生成标准 Form,常用于自定义搭建配置界面生成

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import { useEffect, useMemo, useRef } from 'react'; function useDebouncedCallback(func, wait, options) { var _this = this; var lastCallTime = useRef(null); var lastInvokeTime = useRef(0); var timerId = useRef(null); var lastArgs = useRef([]); var lastThis = useRef(); var result = useRef(); var funcRef = useRef(func); var mounted = useRef(true); funcRef.current = func; // Bypass `requestAnimationFrame` by explicitly setting `wait=0`. var useRAF = !wait && wait !== 0 && typeof window !== 'undefined'; if (typeof func !== 'function') { throw new TypeError('Expected a function'); } wait = +wait || 0; options = options || {}; var leading = !!options.leading; var trailing = 'trailing' in options ? !!options.trailing : true; // `true` by default var maxing = ('maxWait' in options); var maxWait = maxing ? Math.max(+options.maxWait || 0, wait) : null; useEffect(function () { mounted.current = true; return function () { mounted.current = false; }; }, []); // You may have a question, why we have so many code under the useMemo definition. // // This was made as we want to escape from useCallback hell and // not to initialize a number of functions each time useDebouncedCallback is called. // // It means that we have less garbage for our GC calls which improves performance. // Also, it makes this library smaller. // // And the last reason, that the code without lots of useCallback with deps is easier to read. // You have only one place for that. var debounced = useMemo(function () { var invokeFunc = function invokeFunc(time) { var args = lastArgs.current; var thisArg = lastThis.current; lastArgs.current = lastThis.current = null; lastInvokeTime.current = time; return result.current = funcRef.current.apply(thisArg, args); }; var startTimer = function startTimer(pendingFunc, wait) { if (useRAF) cancelAnimationFrame(timerId.current); timerId.current = useRAF ? requestAnimationFrame(pendingFunc) : setTimeout(pendingFunc, wait); }; var shouldInvoke = function shouldInvoke(time) { if (!mounted.current) return false; var timeSinceLastCall = time - lastCallTime.current; var timeSinceLastInvoke = time - lastInvokeTime.current; // Either this is the first call, activity has stopped and we're at the // trailing edge, the system time has gone backwards and we're treating // it as the trailing edge, or we've hit the `maxWait` limit. return !lastCallTime.current || timeSinceLastCall >= wait || timeSinceLastCall < 0 || maxing && timeSinceLastInvoke >= maxWait; }; var trailingEdge = function trailingEdge(time) { timerId.current = null; // Only invoke if we have `lastArgs` which means `func` has been // debounced at least once. if (trailing && lastArgs.current) { return invokeFunc(time); } lastArgs.current = lastThis.current = null; return result.current; }; var timerExpired = function timerExpired() { var time = Date.now(); if (shouldInvoke(time)) { return trailingEdge(time); } // https://github.com/xnimorz/use-debounce/issues/97 if (!mounted.current) { return; } // Remaining wait calculation var timeSinceLastCall = time - lastCallTime.current; var timeSinceLastInvoke = time - lastInvokeTime.current; var timeWaiting = wait - timeSinceLastCall; var remainingWait = maxing ? Math.min(timeWaiting, maxWait - timeSinceLastInvoke) : timeWaiting; // Restart the timer startTimer(timerExpired, remainingWait); }; var func = function func() { var time = Date.now(); var isInvoking = shouldInvoke(time); for (var _len = arguments.length, args = new Array(_len), _key = 0; _key < _len; _key++) { args[_key] = arguments[_key]; } lastArgs.current = args; lastThis.current = _this; lastCallTime.current = time; if (isInvoking) { if (!timerId.current && mounted.current) { // Reset any `maxWait` timer. lastInvokeTime.current = lastCallTime.current; // Start the timer for the trailing edge. startTimer(timerExpired, wait); // Invoke the leading edge. return leading ? invokeFunc(lastCallTime.current) : result.current; } if (maxing) { // Handle invocations in a tight loop. startTimer(timerExpired, wait); return invokeFunc(lastCallTime.current); } } if (!timerId.current) { startTimer(timerExpired, wait); } return result.current; }; func.cancel = function () { if (timerId.current) { useRAF ? cancelAnimationFrame(timerId.current) : clearTimeout(timerId.current); } lastInvokeTime.current = 0; lastArgs.current = lastCallTime.current = lastThis.current = timerId.current = null; }; func.isPending = function () { return !!timerId.current; }; func.flush = function () { return !timerId.current ? result.current : trailingEdge(Date.now()); }; return func; }, [leading, maxing, wait, maxWait, trailing, useRAF]); return debounced; } export default useDebouncedCallback;