不理解官方的一個(gè)faqlinkIfthefunctionyou’rememoizingisaneventhandlerandisn’tusedduringrendering上邊這句話是官方的原話,但我覺(jué)得沒(méi)什么道理...在我看來(lái)下面兩種寫(xiě)法沒(méi)有任何區(qū)別,請(qǐng)指點(diǎn);importReact,{useState,useCallback,useEffect,useRef}from'react';functionForm(){const[text,updateText]=useState('');consttextRef=useRef();useEffect(()=>{textRef.current=text;//Writeittotheref});consthandleSubmit=useCallback(()=>{constcurrentText=textRef.current;//Readitfromtherefconsole.log(currentText);},[textRef]);//Don'trecreatehandleSubmitlike[text]woulddo//consthandleSubmit=useCallback(()=>{//console.log(text);//},[text]);return(updateText(e.target.value)}/>click);}exportdefaultForm;
對(duì)useCallback官方例子的不理解?
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2019-04-27 22:14:37