Nansi indlela yokuhlela isihloko sakho esiceliwe mayelana nokusabela kwe-โuserefโ:
I-React ilabhulali eyaziwa emhlabeni wonke yokudala izixhumanisi zomsebenzisi, ikakhulukazi izinhlelo zokusebenza zekhasi elilodwa. Iwumtapo wezincwadi ongasindi futhi ovumelana nezimo oklanyelwe ukuthuthukisa ulwazi lomsebenzisi. Ukuthuthukiswa kwewebhu sekufinyelele kuma-horizons amasha ngezici ezifana nama-Hooks alethwe yi-React. Esinye isici esibalulekile esinjalo, noma ungasicabangela, ihuku elinikezwe i-React lithi useRef. UseRef ngokuvamile isetshenziselwa ukufinyelela amanodi e-DOM noma izakhi ze-React.
Ku-React, ukunikezwa kwengxenye yomsebenzi akubikezeleki. Ngakho-ke, uma sihlose ukuthwebula inani futhi sifuna ukuthi liqhubeke ngokuhamba kwesikhathi ngaphandle kokubangela noma yikuphi ukunikezwa kabusha, singasebenzisa useRef Hook.
Umehluko omkhulu phakathi kwe-useRef namanye amahhuku ku-React uthi - ayibangeli ukuphinda kunikeze. Kunalokho, ivumela inani eligciniwe ukuthi liqhubeke kukho konke ukunikezwa kabusha.
Manje, ake sibheke ngokujulile i-useRef Hook, ukusetshenziswa kwayo, nokuthi singazixazulula ngempumelelo kangakanani izinkinga ngokuyisebenzisa.
Ukuqonda ukusetshenziswa kweRef Hook ku-React
Ngamagama alula, i-useRef iyi-React Hook eyakhelwe ngaphakathi ekuvumela ukuthi ulandelele inani eliguquguqukayo elingaqhubeka lidlule umjikelezo wempilo ojwayelekile wokunikeza, uma uqhathaniswa nezibonelo eziguquguqukayo engxenyeni yekilasi ku-React.
import React, { useRef } from 'react'; function App() { const ourRef = useRef(null); return (<div>Do something...</div>); }
I-useRef Hook iqalwa nge-agumenti eyize, futhi ibuyisela into engaguquki kukho konke ukuphila kwengxenye.
Ukuqaliswa Okungokoqobo kokusetshenziswaRef
Ake sizame ukusebenzisa useRef esimweni sangempela sempilo. Cabangela isimo lapho kufanele ugxilise khona okokufaka kombhalo ngokushesha nje lapho ingxenye yakho ikhwela ku-DOM.
Indlela evamile ingadinga ukuqonda Izindlela ze-Lifecycle, njenge-componentDidMount njll., kuyilapho i-useRef Hook yenza umsebenzi uqonde.
import React, { useEffect, useRef } from 'react'; function TextInputWithFocusButton() { const inputEl = useRef(null); useEffect(() => { if(inputEl !== null) { inputEl.current.focus(); } }, []); return ( <> <input ref={inputEl} type="text" /> <button onClick={() => inputEl.current && inputEl.current.focus()}> Focus the input </button> </> ); }
Lapha, sisebenzise i-useRef Hook ukuze sibhekisele entweni yethu yokufaka. I-useEffect Hook isetshenziselwa ukuletha okokufaka ekugxilweni ngokushesha nje lapho ingxenye ikhwela ku-DOM.
Ukusebenzisa useRef Neminye Imitapo yolwazi
Akuyona into engavamile ukuthola izimo lapho i-useRef izosetshenziswa khona neminye imitapo yolwazi nemisebenzi. Isibonelo, inhlanganisela ye-useRef ne-useEffect isetshenziswa kakhulu ezimeni lapho umuntu edinga ukudala isenzakalo selabhulali yezinkampani zangaphandle.
I-useRef hook ku-React iletha ukuguquguquka nokusebenza kahle, futhi ukuqonda ukusetshenziswa kwayo okufanele kungaba isiguquli segeyimu kunoma yimuphi unjiniyela we-React.
Sicela ukhumbule, ikhodi engenhla kanye nemininingwane yokusebenzisa ikufomethi ye-TypeScript, okuyi-superset ethayiphiwe ngokwezibalo ye-JavaScript enezela izinhlobo ozikhethela olimini. I-TypeScript ayigcini nje ngokwenza i-JavaScript ibe yesimanje kodwa futhi inikeza amathuluzi angcono futhi inike amandla amaphethini wokuhlela akhiqiza kakhulu.
Manje ake sishintshe amagiya sikhulume ngamathrendi nezitayela zemfashini. Imfashini, njengokwenza izinhlelo, ishintsha njalo, iyashintsha njalo. Umlando wemfashini nawo unemibalabala futhi unamandla, ngenkathi ngayinye ikhombisa izitayela namathrendi ahlukene - kusukela enkathini yokunethezeka yama-Victorian kuya ekubukekeni okungokwengqondo kweminyaka yama-70s, kuya emfashinini echumayo yesitayela somgwaqo yanamuhla.
- I-Roaring 20s yazala isitayela 'se-flapper', esibonakala ngezinwele eziphunguliwe, izingubo ezixegayo, ezifika emadolweni, kanye nezinselele eziningi namasenki.
- Ngama-50s, 'Ukubukeka Okusha' kaChristian Dior - okhalo olucijile neziketi ezigcwele - kwaba yisibonelo sobuhle.
- Iminyaka yawo-60 yayimayelana nenkululeko, ubusha, nokuzijabulisa. Sibone ukuphrinta okugqamile, imibala ye-neon, iziketi ezincanyana, namabhuzu ahambayo.
- Iminyaka yama-90s yabona ukwanda kwesitayela se-minimalism, i-grunge nesitayela somgwaqo, ngamafulana amakhulu, ama-crop top, nama-baggy jeans okuyisisekelo.
Nakuba okwedlule kubumba umhlaba wemfashini, ukuqamba izinto ezintsha kanye nobuciko okuvula indlela eya phambili. Njengasekuhlelweni, kubalulekile ukuqonda nokuhlonipha okwedlule kodwa futhi uhlale ubheke phambili kuthrendi enkulu elandelayo.