Video: Puas muaj cov ntsiab lus hauv JavaScript?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
TL; DR: Nyob ntawd yog NO pointers hauv JavaScript thiab cov ntaub ntawv xa mus ua haujlwm txawv ntawm qhov peb ib txwm pom hauv feem ntau lwm yam lus nrov programming. Hauv JavaScript , nws tsuas yog tsis tuaj yeem muaj kev siv los ntawm ib qho sib txawv mus rau lwm qhov sib txawv. Thiab, tsuas yog qhov tseem ceeb sib xyaw (Object, Array) tuaj yeem raug muab los ntawm kev siv.
Tsis tas li ntawd, tus pointer hauv JavaScript yog dab tsi?
Simulating pointers hauv JavaScript . A taw tes yog qhov hloov pauv tau los ntawm qhov koj tuaj yeem nkag mus (nyeem lossis hloov kho) lwm qhov sib txawv. Piv txwv li, txoj haujlwm A tuaj yeem hu ua haujlwm B thiab dhau nws a taw tes rau ib qho ntawm A's local variables.
Ib tug kuj yuav nug, yog JavaScript txoj haujlwm los ntawm kev siv? Nyob rau variable txoj haujlwm , scalar primitive values (Number, String, Boolean, undefined, null, Symbol) yog muab-los-tus nqi thiab cov nqi sib xyaw yog muab-los- siv . Cov cov ntaub ntawv hauv JavaScript tsuas yog taw tes ntawm qhov muaj nuj nqis thiab TSIS ntawm lwm yam hloov pauv, lossis cov ntaub ntawv.
Hauv qhov no, koj siv cov pointers hauv JavaScript li cas?
Tsis yog, JS tsis muaj taw tes . Cov khoom raug dhau los ntawm kev dhau ib daim qauv ntawm kev siv. Tus programmer tsis tuaj yeem nkag mus rau C-zoo li "tus nqi" sawv cev qhov chaw nyob ntawm ib qho khoom.
Puas muaj cov taw qhia hauv Python?
Cov taw qhia tsis muaj nyob rau hauv Python . Tab sis, peb siv tib tus cwj pwm nrog cov khoom sib hloov. Cov Taw tes peb siv nrog ctypes yog tiag C taw tes.
Pom zoo:
Thaum koj reboot koj lub kaw lus lub computer ua raws li pib cov lus qhia khaws cia rau hauv hom kev nco Pawg ntawm cov lus teb xaiv?
Teb Cov Kws Tshaj Lij Tshaj Lij Tshaj Tawm Ib lub khoos phis tawj pib cov lus qhia tau muab khaws cia rau hauv hom nco hu ua Flash. Flash nco tuaj yeem sau rau thiab nyeem los ntawm, tab sis nws cov ntsiab lus tsis raug tshem tawm tom qab lub khoos phis tawj kaw. Lub cim xeeb Flash no feem ntau hu ua BIOS (Basic Input Output System)
Dab tsi yog lub ntsiab lus ntawm cov lus tsis hais lus?
Tsis hais lus. Cov ntaub ntawv xav tau sib txuas lus hauv kev sib pauv kev sib raug zoo los ntawm cov cim qhia nrog cov lus siv hauv kev hais lus. Xws li cues muaj xws li lub cev lus, lub suab, inflexion, thiab lwm yam ntawm lub suab, hnav ris tsho, thiab lwm yam. Saib kuj tsis hais lus
Puas muaj ib txoj hauv kev pov tseg qhov kev kuaj xyuas los ntawm txoj kev uas tsis muaj cov lus pov tseg?
9 Teb. Koj tuaj yeem pov cov kev txwv tsis raug txheeb xyuas yam tsis tas yuav tshaj tawm lawv yog tias koj xav tau tiag tiag. Unchecked kev zam txuas ntxiv RuntimeException. Throwables uas txuas ntxiv yuam kev tseem tsis tau txheeb xyuas, tab sis tsuas yog yuav tsum tau siv rau cov teeb meem loj tiag tiag (xws li invalid bytecode)
Muaj pes tsawg lub ntsiab lus tseem ceeb tam sim no tau txhais hauv Java lus Mcq?
Hauv Java programming lus, lo lus tseem ceeb yog ib qho ntawm 51 cov lus tshwj tseg uas muaj lub ntsiab lus ua ntej hauv hom lus; vim li no, programmers tsis tuaj yeem siv lo lus tseem ceeb los ua cov npe sib txawv, txoj hauv kev, chav kawm, lossis lwm yam kev txheeb xyuas. Ntawm 51 lo lus tseem ceeb no, 49 tau siv thiab 2 tsis siv
Puas yog txhua yam lus muaj cov npe thiab cov lus qhia?
Lus Askiv universal. Ib hom lus thoob ntiaj teb yog ib qho qauv uas tshwm sim nyob rau hauv cov hom lus ntuj, muaj peev xwm muaj tseeb rau txhua tus ntawm lawv. Piv txwv li, Txhua hom lus muaj cov npe thiab cov lus qhia, lossis Yog hais tias ib hom lus tau hais, nws muaj tus lej thiab tus lej