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  • React Hook~部分实用钩子

    useCompareEffect

    /**
     * useCompareEffect
     * useEffect只是普通的浅比较,这里做了深比较
     * useEffect的依赖是否相同,相同不触发
     */
    import { useEffect, useRef } from 'react'
    import { isEqual } from 'lodash'
    
    export default function useCompareEffect(effect: React.EffectCallback, dependencies?: Object) {
      function deepCompareDependencies(value: any) {
        const ref = useRef()
    
        if (!isEqual(value, ref.current)) {
          ref.current = value
        }
    
        return ref.current
      }
    
      useEffect(effect, deepCompareDependencies(dependencies))
    }
    

    useDependencyEffect

    /**
     * 组件 componentDidMount 的时候不执行 useEffect 的方法
     * 只有依赖变化的时候会执行
     */
    import { useRef, useEffect } from 'react'
    
    export default function useDependencyEffect(effect: React.EffectCallback, dependencies: any[]) {
      const componentDidMount = useRef<boolean>(false)
    
      useEffect(() => {
        if (componentDidMount.current) {
          effect()
        }
      }, dependencies)
    
      /**
       * 必须放在最底下
       */
      useEffect(() => {
        componentDidMount.current = true
      }, [])
    }
    
    

    react不支持useState回调,建议采用useEffect,这里做了个useState的回调

    
    /** useStateCallback setstate回调 */
    export function useStateCallback<T>(initialState: T | (() => T)): [T, DispatchWithCallback<SetStateAction<T>>] {
      const [state, _setState] = useState(initialState);
    
      const callbackRef = useRef<Callback<T>>();
      const isFirstCallbackCall = useRef<boolean>(true);
    
      const setState = useCallback((setStateAction: SetStateAction<T>, callback?: Callback<T>): void => {
        callbackRef.current = callback;
        _setState(setStateAction);
      }, []);
    
      useEffect(() => {
        if (isFirstCallbackCall.current) {
          isFirstCallbackCall.current = false;
          return;
        }
        callbackRef.current?.(state);
      }, [state]);
    
      return [state, setState];
    }
    
    // 使用: const [state, setstate] = useStateCallback()
    
    

    基于ant4 prompt优化

    /**
     * 离开页面prompt
     */
    import React, { SetStateAction, useMemo, useState, useCallback, useRef, useEffect, ReactNode } from 'react'
    import { Prompt, useHistory } from 'umi';
    import { Modal } from 'antd';
    
    type Callback<T> = (value?: T) => void;
    type DispatchWithCallback<T> = (value: T, callback?: Callback<T>) => void;
    
    /** useStateCallback setstate回调 */
    export function useStateCallback<T>(initialState: T | (() => T)): [T, DispatchWithCallback<SetStateAction<T>>] {
      const [state, _setState] = useState(initialState);
    
      const callbackRef = useRef<Callback<T>>();
      const isFirstCallbackCall = useRef<boolean>(true);
    
      const setState = useCallback((setStateAction: SetStateAction<T>, callback?: Callback<T>): void => {
        callbackRef.current = callback;
        _setState(setStateAction);
      }, []);
    
      useEffect(() => {
        if (isFirstCallbackCall.current) {
          isFirstCallbackCall.current = false;
          return;
        }
        callbackRef.current?.(state);
      }, [state]);
    
      return [state, setState];
    }
    
    interface Iprops {
      isPrompt: boolean
      content?: string
    }
    
    export default function UsePrompt(props: Iprops) {
      const [promptStatus, setpromptStatus] = useStateCallback(props.isPrompt)
      const history = useHistory()
      useEffect(() => {
        setpromptStatus(props.isPrompt)
      }, [props.isPrompt])
    
      return (<>
        <Prompt
          when={promptStatus}
          message={location => {
    
            Modal.confirm({
              title: '提示',
              content: props.content || '确认离开吗?系统可能不会保存当前表单',
              okText: '确认',
              cancelText: '取消',
              onOk: () => {
                setpromptStatus(false, () => {
                  history.push(location.pathname)
                  return false
                })
              }
            });
            return false;
          }}
        />
      </>)
    }
    
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  • 原文地址:https://www.cnblogs.com/mapleChain/p/12996510.html
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