Video: Dab tsi yog hom kev pom ntawm cov khoom hauv chav kawm?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Peb Pom kev Qib
Hauv OOP PHP peb muaj peb pom kev qib rau cov khoom thiab cov txheej txheem ntawm a chav kawm : public, tiv thaiv, thiab private. Pom kev tau tshaj tawm tias siv a pom kev lo lus tseem ceeb tshaj tawm tias qib twg pom kev ib yam khoom lossis txoj kev muaj.
Ntxiv mus, dab tsi yog qhov kev pom ntawm chav kawm?
Pom kev yog ib feem loj ntawm OOP. Nws tso cai rau koj los tswj koj qhov twg chav kawm cov tswv cuab tuaj yeem nkag tau los ntawm, piv txwv li txhawm rau tiv thaiv qee qhov hloov pauv hloov los ntawm sab nraud chav kawm . Lub neej ntawd pom kev yog pej xeem, uas txhais tau hais tias lub chav kawm cov tswv cuab tuaj yeem nkag los ntawm txhua qhov chaw.
Ib tug kuj yuav nug, dab tsi yog pob visibility? Interfaces coj zoo li cov chav kawm hauv pob khoom . Ib qho interface tuaj yeem tshaj tawm rau pej xeem kom pom sab nraum nws pob . Hauv qab lub neej ntawd pom kev , ib qho interface yog pom tsuas yog hauv nws pob . Lub ntsiab lus ntawm kev tiv thaiv ntiag tug yog txwv pom kev nruj me ntsis rau subclasses (thiab tshem tawm pob nkag mus).
Xav txog qhov no, dab tsi yog hom kev pom kev ntawm cov chav kawm muab tau?
Kev nkag tau ntawm lub hauv paus chav kawm los ntawm muab cov chav kawm yog tswj los ntawm hom kev pom pom . Peb hom kev pom pom yog ntiag tug, tiv thaiv thiab pej xeem. Lub neej ntawd hom kev pom yog tus kheej.
Dab tsi yog qhov pom kev pom ntawm chav kawm hauv Java?
Java : Los ntawm ua ntej , cov chav kawm pom kev yog pob ntiag tug, piv txwv li tsuas pom rau chav kawm nyob rau hauv tib lub pob. Cov chav kawm tsis muaj pom kev txhais zoo li hauv Java . Lawv pom tau yog tias koj muab lawv tso rau hauv chav sib sau ua ke.
Pom zoo:
Dab tsi ntawm cov hauv qab no yog qhov zoo ntawm kev siv cov khoom siv pom kev hauv kev hais lus?
Qhov txiaj ntsig tseem ceeb ntawm kev siv cov khoom siv pom hauv koj cov lus hais yog tias lawv ua kom cov neeg tuaj saib muaj kev txaus siab, hloov kev mloog ntawm tus neeg hais lus, thiab ua rau tus neeg hais lus muaj kev ntseeg siab ntau dua hauv kev nthuav qhia tag nrho
Dab tsi yog ob chav kawm tshwj xeeb hauv hierarchy ntawm Java zam chav kawm?
Chav Kawm Exception muaj ob lub ntsiab subclasses: IOException class thiab RuntimeException Class. Hauv qab no yog cov npe ntawm feem ntau kuaj xyuas thiab tsis tau txheeb xyuas Java's Built-in Exceptions
Puas txhais tau tias yog kev sib raug zoo ntawm cov khoom ntawm ib yam khoom thiab lub peev xwm ntawm tus neeg sawv cev uas muab cov lus qhia rau kev siv cov khoom?
Kev them nyiaj yog kev sib raug zoo ntawm cov khoom ntawm ib yam khoom thiab lub peev xwm ntawm tus neeg sawv cev uas txiav txim siab seb qhov khoom siv tau li cas
Chav kawm piav qhia txog tus qauv ntawm chav kawm yog dab tsi?
Nyob rau hauv object-oriented programming, ib chav kawm yog ib tug template txhais ntawm txoj kev s thiab txawv txawv s nyob rau hauv ib tug tej yam khoom. Yog li, ib yam khoom yog ib qho piv txwv tshwj xeeb ntawm chav kawm; nws muaj cov txiaj ntsig tiag tiag tsis yog hloov pauv. Cov qauv ntawm ib chav kawm thiab nws cov subclasses yog hu ua chav kawm hierarchy
Dab tsi yog kev siv cov ntawv cim kev cai li cas koj nkag mus rau hauv Apex cov chav kawm thiab hauv Visualforce nplooj ntawv?
Cov ntawv sau kev cai tso cai rau cov neeg tsim khoom tsim cov ntawv thov ntau hom lus los ntawm kev nthuav qhia cov ntaub ntawv (piv txwv li, pab cov ntawv lossis cov lus yuam kev) hauv tus neeg siv hom lus. Cov ntawv sau kev cai yog cov ntawv sau muaj txiaj ntsig uas tuaj yeem nkag tau los ntawm Apex cov chav kawm, nplooj ntawv Visualforce, lossis cov khoom siv xob laim