Video: Cov chav kawm pseudo thiab cov ntsiab lus pseudo yog dab tsi?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Yeej a pseudo - chav kawm yog ib qho selector uas pab xaiv ib yam dab tsi uas tsis tuaj yeem qhia los ntawm tus xaiv yooj yim, piv txwv li:hover. A pseudo - keeb txawm li cas los xij tso cai rau peb los tsim cov khoom uas tsis ib txwm muaj nyob hauv daim ntawv ntoo, piv txwv li ':: tom qab'.
Yog li ntawd, dab tsi yog pseudo ntsiab?
Ib CSS pseudo - keeb yog ib lo lus tseem ceeb ntxiv rau lub selector uas cia koj style ib feem ntawm cov xaiv keeb (s). Piv txwv li,:: thawj kab tuaj yeem siv los hloov font ntawm thawj kab ntawm kab lus.
Tsis tas li ntawd, cov chav kawm pseudo yog dab tsi? Ib CSS pseudo - chav kawm yog ib lo lus tseem ceeb ntxiv rau tus xaiv uas qhia txog lub xeev tshwj xeeb ntawm cov khoom xaiv. Piv txwv li,:hover tuaj yeem siv los hloov lub pob xim thaum tus neeg siv lub pointer hovers tshaj nws.
Ib yam li ntawd, nws tau nug, qhov txawv ntawm cov ntsiab lus pseudo thiab cov chav kawm pseudo yog dab tsi?
A pseudo - chav kawm zoo ib yam li a chav kawm hauv HTML, tab sis nws tsis tau teev meej meej hauv markup. Ib txhia pseudo - chav kawm yog dynamic-lawv tau thov raws li cov neeg siv kev cuam tshuam nrog cov ntaub ntawv. A pseudo - keeb hais txog tej yam uas yog ib feem ntawm cov ntaub ntawv, tab sis koj tsuas yog tsis paub nws tseem. Piv txwv li thawj tsab ntawv.
Cov ntsiab lus pseudo puas muaj cov ntsiab lus pseudo?
Pseudo - keeb tso cai rau koj tsim / txhais cov ntsiab lus uas tsis nyob ntawm DOM. Lawv tso cai rau koj style ib feem ntawm ib qho lub ntsiab cov ntsiab lus. Pseudo - cov ntsiab lus muaj tsis muaj keeb ntaus ntawv kom deb li deb raws li cov ntaub ntawv hais txog vim hais tias, tsuas yog lawv tsis muaj nyob hauv DOM. Thiab ua tau tsuas yog tsim siv CSS.
Pom zoo:
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