Video: Koj yuav kuaj xyuas li cas yog ib lub caij muaj ib chav kawm tshwj xeeb hauv jQuery?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Cov hasClass() method checks yog ib yam ntawm tus xaiv cov ntsiab lus muaj cov chav kawm tshwj xeeb npe. Yog TXOJ CAI ntawm tus xaiv cov ntsiab lus muaj cov chav kawm tshwj xeeb lub npe, txoj kev no yuav rov qab "tseeb".
Yog li ntawd, koj yuav ua li cas xyuas seb lub ntsiab lus muaj cov chav kawm hauv jQuery li cas?
Siv. Rau tshawb xyuas yog tias muaj ib qho hauv jQuery muaj chav kawm , ua raws li no syntax: $(selector). hasClass(className); Tus selector yog siv los qhia qhov cov ntsiab lus rau kuaj.
Ib sab saum toj no, yog jQuery ib txoj kev? yog (selector) txoj kev tshawb xyuas qhov kev xaiv tam sim no tawm tsam ib qho kev qhia thiab rov qab muaj tseeb, yog tias tsawg kawg ib lub ntsiab lus ntawm kev xaiv haum rau tus xaiv tau muab. Yog tias tsis muaj cov khoom haum, lossis tus neeg xaiv tsis siv tau, ces cov lus teb yuav yog 'false'.
Tsis tas li ntawd, koj yuav kuaj xyuas li cas yog tias ib qho khoom muaj chav kawm?
phim () los txiav txim yog hais tias ib yam khoom muaj chav kawm . className tsuas yog ib txoj hlua xwb ces koj tuaj yeem siv indexOf ua haujlwm tsis tu ncua kom pom yog lis of cov chav kawm muaj lwm txoj hlua. Yog tus keeb nkaus xwb muaj ib chav kawm npe koj tuaj yeem sai kuaj nws los ntawm kev chav kawm tus cwj pwm.
Kuv tuaj yeem siv classList toggle?
Txhais thiab siv Cov cuab yeej no pab tau rau ntxiv , tshem tawm thiab toggle CSS cov chav kawm ntawm ib lub ntsiab lus. Cov classList Cov cuab yeej yog nyeem nkaus xwb, txawm li cas los xij, koj ua tau hloov kho los ntawm siv tus ntxiv () thiab tshem tawm txoj kev. Kev daws teeb meem hla browser: Cov classList cov cuab yeej tsis txhawb nqa hauv IE9 thiab ua ntej.
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