Video: Dab tsi yog cov ntaub ntawv npaj hauv JavaScript?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Cov npaj () txoj kev yog siv los ua kom muaj nuj nqi tom qab lub ntaub ntawv yog loaded. Xijpeem code koj sau hauv $( ntaub ntawv ). npaj () txoj kev yuav khiav thaum nplooj ntawv DOM yog npaj ua JavaScript code.
Ntawm no, cov ntaub ntawv npaj tau txhais li cas?
Cov cov ntaub ntawv npaj txhij xwm txheej qhia tias DOM ntawm nplooj ntawv yog tam sim no npaj , yog li koj tuaj yeem tswj hwm nws yam tsis muaj kev txhawj xeeb tias qhov chaw ntawm DOM tseem tsis tau tsim. Cov cov ntaub ntawv npaj txhij kev tshwm sim hluav taws ua ntej tag nrho cov duab thiab lwm yam yog loaded, tab sis tom qab tag nrho DOM nws tus kheej npaj txhij.
Ib sab saum toj no, vim li cas peb thiaj xav tau $(document ready()?Muaj ob peb lub laj thawj vim li cas koj thiaj siv $(cov ntaub ntawv ). npaj () hauv koj cov ntawv sau: Koj xav tau kom paub tseeb tias nplooj ntawv yog tag nrho loaded ua ntej koj tsab ntawv executes. Koj tsis muaj kev tswj xyuas qhov twg koj tsab ntawv tau thauj khoom.
Hais txog qhov no, cov ntaub ntawv npaj ua haujlwm li cas?
Lub jQuery cov ntaub ntawv npaj txhij kev ua haujlwm ua haujlwm thaum DOM ( Cov ntaub ntawv Object Model) yog tag nrho loaded nyob rau hauv lub browser. jQuery cov ntaub ntawv npaj txhij yog siv los pib jQuery/JavaScript code tom qab DOM yog npaj , thiab feem ntau siv thaum ua haujlwm nrog jQuery. Javascript/jQuery code hauv $( ntaub ntawv ).
Peb puas tuaj yeem siv ntau daim ntawv npaj ua haujlwm?
Yog lawm, koj tuaj yeem siv ntau daim ntawv npaj handler, tsis muaj qhov tshwj xeeb kom zoo dua txawm tias koj siv tau jQuery code nyob rau hauv ntau qhov chaw. Koj ua tau 't siv qhov sib txawv hauv ib qho hauv lwm qhov vim tias cov no nyob hauv qhov sib txawv.
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