Keys pab React txheeb xyuas cov khoom twg tau hloov pauv, ntxiv, lossis raug tshem tawm. Cov yuam sij yuav tsum tau muab rau cov ntsiab lus hauv cov array kom muab cov ntsiab lus ruaj khov: tus lej const=[1, 2, 3, 4, 5]; const listItems=tooj .
Lub hom phiaj ntawm qhov tseem ceeb yog dab tsi thaum ua cov npe ntawm cov khoom?
React's key prop muab koj lub peev xwm los tswj cov khoom piv txwv. Txhua zaus React ua rau koj cov khoom, nws hu koj lub luag haujlwm los khaws cov React tshiab uas nws siv los hloov kho DOM. Yog tias koj rov qab cov khoom qub qub, nws khaws cov khoom siv / DOM nodes nyob ib puag ncig, txawm tias tag nrho cov khoom hloov pauv .
Cov yuam sij hauv React yog dab tsi thiab vim li cas koj thiaj yuav tsum siv lawv nrog cov npe?
Ib "tus yuam sij" yog ib txoj hlua tshwj xeeb uas koj xav tau suav nrog thaum tsim cov npe ntawm cov ntsiab lus hauv React. Cov yuam sij yog siv los ua React txhawm rau txheeb xyuas cov khoom hauv cov npe hloov pauv, hloov kho, lossis tshem tawm. Hauv lwm lo lus, peb tuaj yeem hais tias cov yuam sij raug siv los muab tus kheej rau cov ntsiab lus hauv cov npe .
Tus yuam sij yog dab tsi?
KeyShot coj koj real-time 3D rendering uas tso tawm cov txiaj ntsig tam sim thiab txo lub sijhawm los tsim cov khoom muag pom tseeb. KeyShot tau ntseeg los ntawm cov npe thoob ntiaj teb rau nws qhov nrawm, yooj yim ntawm kev siv, cov ntaub ntawv raug tshawb fawb, thiab cov khoom siv kho kom zoo tshaj plaws .
Tus yuam sij Mcq yog dab tsi?
"Key" prop yog ib txoj hauv kev rau React txhawm rau txheeb xyuas cov khoom tshiab tshiab hauv ib daim ntawv teev npe thiab sib piv thaum lub sijhawm"diffing" algorithm .
ReactJS Tutorial - 17 - List Rendering
