Dab tsi yog qhov HTML Tag Versus ib qho HTML Element?

Muaj Qhov Sib Tham Ntawm Cov Kev Nkag Ob

Web tsim, zoo li txhua txoj kev lag luam lossis txoj hauj lwm, muaj ib hom lus nws tus kheej. Thaum koj nkag mus rau hauv kev lag luam thiab pib hais lus rau koj cov phooj ywg, koj yuav tseeg mus rau hauv cov lus thiab cov nqe lus uas yog tshiab rau koj, tiam sis qhov uas khiav tawm ntawm koj tus kws qhia ntawv hauv koj tus khub. Ob ntawm cov nqe lus uas koj yuav hnov ​​yog HTML "lossis" thiab "element".

Thaum koj hnov ​​cov lus ob nqe lus no, koj yuav paub tau tias lawv raug siv sib txuas me ntsis. Raws li xws li, ib lo lus nug uas muaj ntau tus kws tshaj lij hauv web muaj thaum lawv pib ua hauj lwm nrog HTML chaws yog "qhov txawv ntawm qhov HTML Tag thiab HTML Element?"

Thaum uas ob nqe lus no zoo sib xws nyob rau hauv lub ntsiab lus, lawv tsis yog cov lus tiag tiag. Yog li dab tsi yog qhov zoo sib thooj nrog cov lus ob? Cov lus teb luv yog tias ob qho tags thiab cov ntsiab lus xa mus rau qhov cim sau rau HTML. Piv txwv, koj yuav hais tias koj siv

lossis los txheeb ib pawg lus los yog keeb los tsim kev sib txuas. Muaj ntau tus neeg siv cov lus cim lossis lub tsho sib hloov, thiab txhua tus kws tsim tawm lossis tus tsim tawm koj tham nrog yuav nkag siab txog yam koj meant, tiam sis qhov kev muaj tiag yog tias muaj qhov txawv ntawm qhov ob lo lus.

HTML yog ib hom lus cim lus , uas txhais tau hais tias nws yog sau nrog cov cai uas nyeem tau los ntawm ib tug neeg tsis tas nws yuav tsum tau muab tso ua ke ua ntej. Hauv ntawv, cov ntawv nyeem ntawm cov vev xaib yog "cim" nrog rau cov zauv no kom muab cov lus qhia hauv web browser los tso saib cov ntawv nyeem. Cov cim npe cim npe yog cov cim npe ntawm lawv tus kheej HTML.

Thaum koj sau HTML, koj sau HTML cim npe. Tag nrho cov cim npe HTML yog ua los ntawm ntau qhov chaw, xws li:

• Ib qho tsawg-tshaj kos npe <
• Ib lo lus los yog tus cwj pwm uas txiav txim siab uas sau rau hauv daim ntawv sau npe
• Cov naj npawb ntawm cov yeem tshwjxeeb hauv HTML hauv daim ntawv ntawm lub npe = "tus nqi" pauv
• Thiab thaum kawg ib qho ntau dua-dua kos npe>

Piv txwv, ntawm no yog qee cov HTML cim npe:

Cov no yog cov cim tag nrho HTML, tsis muaj cov ntaub ntawv yeem ntxiv rau lawv. Cov cim npe no yog:

• - txhais cov lus.

• - txhais cov nplooj ntawv ua HTML
• - txhais tau qhov faib.

Cov nram qab no tseem yog HTML cim npe:

• Cov piv txwv no muaj xws li cov yeeb yaj duab uas tau muab ntxiv rau cov lus qhib HTML.

  • Tus
    yog daim ntawv teev npe uas tsis suav nrog uas muaj cov cim ID
    • Qhov faib muaj ib tug cwj pwm hauv chav kawm
    • Txuas ntxiv, lossis txuas, cov ntsiab lus muaj xws li "href" attribute
    • Daim duab lossis nrog tus "src" attribute

    Rau cov cim thiab duab cim npe, cov cwj pwm yeej tsis xaiv tau, lawv tsim nyog rau cov cim npe los ua kom zoo. Koj yuav tsum qhia qhov txuas qhov twg mus (qhov no yog qhov "href") thiab cov duab dab tsi los qhia (uas yog qhov "src" attribute).

    HTML Ntsiab Yog Dab Tsi

    Raws li W3C HTML specification, ib lub caij yog qhov yooj yim lub tsev thaiv ntawm HTML thiab feem ntau yog ua los ntawm ob tug cim npe : qhib kev xaus thiab xaus kev xaus. Li ntawd, peb muaj tsuas ntsia ntawm cov cim npe qhib, uas pib lub ntsiab. Yuav kom xaus lub caij no, koj sau cov cim npe xaus.

    Piv txwv, rau cov pawg lus koj sau qhov no:

    Qhov no yog ua los ntawm kev pib qhib uas peb tau pom ib pliag dhau los nrog rau txoj kev xaus-. Cov cim tag nrho tsuas yog cov lus pib dua, tiam sis nrog rau ib qho "luaj tom qab" ntxiv ncaj qha tom qab "tsawg dua tus cim".

    Yuav luag tag nrho cov HTML ntsiab muaj kev pib qhib thiab xaus kev xaus. Cov cim npe no nyob rau hauv cov ntawv nyeem uas yuav tso tawm rau ntawm nplooj ntawv web page. Piv txwv, sau ib nqe lus ntawm cov ntawv nyeem, koj sau cov ntawv los tso rau hauv cov nplooj ntawv thiab tom qab nws nrog cov cim npe no:

    Qhov no yog qhov uas koj yuav sau cov ntawv ntawm cov pawg lus uas koj xav tso tawm rau hauv lub vev xaib.

    Qee cov ntsiab lus HTML tsis tau xaus. Cov no yog hu ua "empty elements". Qee zaum, lawv kuj raug hu ua " singleton " lossis "void" elements. Cov ntsiab lus qhib yog ib qho yooj yim siv vim koj tsuas yog kom muaj ib qho hauv koj qhov web page thiab qhov browser yuav paub tias yuav ua li cas. Piv txwv, ntxiv rau ib txoj kab tawg rau koj nplooj ntawv koj yuav tau siv daim npav b.

    Lwm cov caij nyoog uas tsuas yog muaj ib qho kev pib qhib yog qhov "duab". Piv txwv li:

    Peb pom qhov kev piv txwv dhau los no, tiam sis tsis muaj xaus rau daim duab no. Qhov browser yuav tsuas hloov qhov chaws nrog cov duab uas tau hais los ntawm cov "href" attribute. Hauv qhov no, qhov ntawd yuav yog "logo.png".

    Feem ntau, thaum kuv xa mus rau lub ntsiab lus HTML los yog lossis, kuv yuav siv lub sij hawm "element" los qhia tias kuv tab tom xa mus rau tag nrho cov seem ntawm lub caij (ob qho tag nrho cov lus qhib thiab xaus). Kuv siv \ "lossis \" yog kuv yeej tsuas yog xa ib los yog sib. Qhov no yog txoj kev siv ntawm ob nqe lus no, thiab kuv xav kom koj siv lawv zoo - tab sis cia li paub tias yog koj plam thiab cuam tshuam rau lawv me ntsis, koj yuav tseem yuav to taub los ntawm koj cov phooj ywg tshiab hauv kev pab cuam!

    Thawj tsab xov xwm los ntawm Jennifer Krynin. Edited by Jeremy Girard rau 7/21/17