Yuav ua li cas yog JavaScripts? Basic JavaScript zog

Web-scripts yog cov kev pab uas yog kaw ncaj qha nyob rau hauv ib tug html-code los yog cia li nyob rau hauv cov ntaub ntawv, uas yog ntau preferable. Cov kev pab cuam no sau nyob rau hauv JavaScript. Yog li, sib nrug los ntawm qhov tseeb hais tias xws JavaScripts, peb yuav hais tias nws yog ib tug programming lus uas txhais.

Javascript yog nyeem los ntawm cov browser, thiab ces khiav lub kaw qhia, thiab tswj, uas yog teem saum toj no cov nplooj ntawv. JavaScript nyob rau hauv koj syntax yog zoo li programming hom lus xws li Java, C ++ thiab C.

JavaScript tshuav nws tshwm sim rau cov kev loj hlob ntawm tej tuam txhab uas muag raws li Sun Microsystems (Oracle) thiab Netscape (Mozilla). Tus thawj lub npe ntawm cov lus yog LiveScript. Txawm li cas los, vim rau qhov tseeb hais tias nyob rau ntawm lub sij hawm yog ib tug nrov heev lus Java los ntawm ib lub tuam txhab Tshav Microsystems, Netscape tuam txhab marketing department, nws twb txiav txim siab los hloov lub npe ntawm cov lus nyob rau hauv JavaScript. Thaum zoo li no twb tau muab los xam tias qhov no yog kauj ruam ntxiv qhov nrov hom lus. Tsis tas li ntawd, sib nrug los ntawm qhov tseeb hais tias xws JavaScripts, nws yuav tsum tau muab sau tseg hais tias Java thiab JavaScript yog ob yam lus.

ECMA-262 yog tus nom txheem ntawm cov lus. Lub npe ntawm lub JavaScript lus - ECMAScript.

Rau txoj kev tshawb no ntawm cov lus no yuav pab tau kev paub ua ntej txog CSS thiab Html. Yog hais tias ua ntej lub sij hawm no koj tsis tau paub txog CSS thiab Html, nws yuav tsum tau sai li sai tau paub.

Txwv thiab JavaScript tuition

Cov nram qab no nta tshwm sim nyob rau hauv daim ntawv thov nyob rau hauv lub web-nplooj ntawv ntawm tsab ntawv [tshem tawm]:

• Ntxiv ib tug ntau yam ntawm animation teebmeem, uas yog tsis pom tau hais los ntawm txoj kev Html thiab CSS.
• Muaj peev xwm mus hloov cov Html cov ntsiab lus hais thiab ntxiv tshiab cim npe tsis muaj reloading cov nplooj ntawv.
• Teb rau qho kev tshwm sim (cov lus teb rau cov neeg siv cov tswv yim) - lub processing ntawm keystrokes rau lub keyboard thiab nas cursor.
• Yuav ua raws li cov tshev, uas tau nkag tau rau hauv lub teb ntawm daim ntawv no ua ntej yuav xa nws mus rau lub neeg rau zaub mov. Qhov no thiaj li lub load rau ntawm cov neeg rau zaub mov thiab speeds cov chaw ua hauj lwm qhov chaw.
• Kev txiav txim version ntawm qhov browser thiab thauj cov kev kawm page raws li nyob rau hauv no.

Qhov no yog tsis yog ib tug ua tiav daim ntawv teev cov scripting muaj peev xwm, uas tau raug sau nyob rau hauv cov lus no, JavaScript zog muaj ib tug ntau dav heev lub ntsiab lus.

Nyob rau hauv tas li ntawd mus rau cov nta, muaj ntau cov kev txwv ntawm kev siv scenarios:

• Muaj yog tsis muaj kev nkag tau mus rau cov ntaub ntawv uas yog muab tso rau hauv tus neeg siv lub computer. Nyob rau hauv Feem ntau, tsis muaj kev nkag tau rau sab nraum lub web page nws tus kheej. Qhov kos tej zaum yuav tsuas cov kua nplaum uas hais tias yuav tsum tau nyeem thiab sau ntawv nrog rau JavaScript. Khoom ntawm no hom mas feem ntau yog tsuas tsim nyog rau page load sai.
• Muaj yog tsis muaj tau ntawm tus ntoo khaub lig site queries, piv txwv li nkag mus rau hauv kev nkag mus rau cov nplooj ntawv Web uas nyob rau ntawm ib tug txawv sau, txawm yog hais tias lawv yog qhib nyob rau hauv lub nyob ib sab tabs.
• Yog tsis muaj txoj kev uas yuav kaw lub tabs thiab qhov rais uas tau qhib nrog nws.
• Muaj yog tsis muaj tau ntawm kev tiv thaiv ntawm cov ntawv nyeem nyob rau hauv cov nplooj ntawv thiab kev txwv tsis pub luam dluab lossis cov ntawv luam los ntawm cov nplooj ntawv. Qhov yoojyim tau mus ntxiv ib co kev txwv uas tso cai rau JavaScript zog.

Tej txwv yog nyob rau hauv ib co txoj kev yooj yim rau txim tuag siab phem code.

Yuav ua li cas yog JavaScripts?

Raws li kuv sau tseg saum toj no, JavaScript - ib hom lus uas muab interactivity rau nplooj ntawv Web site. Nrog kev pab los ntawm cov lus no yog cov ntawv sau npe uas muaj nyob rau hauv lub Html-code. Piv txwv li, ib tug sau npe daim ntawv los yog ib tug lus nug sau tawm los ntawm tus neeg siv. JavaScript yog feem ntau tsis meej pem nrog Java, tiam sis ntawm cov lus me ntsis nyob rau hauv ntau.

Ib txhia txawm piv nrog rau lwm cov JavaScript Ruby hom lus, Self, Nab hab sej. Tab sis nws yog ib tug nyias muaj nyias ib yam lus.

siv JavaScript

Siv JavaScript, koj yuav kom hloov mus rau page, hloov lub ntsiab ntawm style, ntxiv los yog tshem tawm cim npe. Nws yog tseem tau mus kawm txog nws cov neeg siv ua nyob rau sab (txo los yog nce cov ua hauj lwm hauv cheeb tsam ntawm lub screen, clicks nrog tus nas, nias tej lag luam, cov nplooj ntawv scrolling). Nws yog ua tau mus nce nkag tau mus rau tej lub caij Html-code thiab manipulation nrog no lub caij. Yog li, lo lus teb rau lo lus nug "yog dab tsi JavaScripts?» Yuav ua tau lub sij hawm los mus download tau cov ntaub ntawv tsis muaj reloading cov nplooj ntawv, cov tswv yim lus, qhov chaw los yog nyeem cov kua nplaum uas thiab ua ntau lwm yam kev ua.

Lub hauv paus ntawm lub uniqueness ntawm JavaScript

Lub ntsiab originality ntawm cov lus no yog hais tias nws muaj kev pab los ntawm yuav luag tag nrho cov browsers thiab muaj tag nrho cov kev koom ua ke nrog lawv. Tag nrho cov kev ua nyob rau hauv JavaScript yog heev yooj yim. Muaj yog tsis muaj lwm yam technology uas accommodates tag nrho cov nyiaj pab. Piv txwv li, yog tsis muaj tus ntoo khaub lig-browser, lawv tsis txaus siab nyob rau hauv tag nrho cov browsers (nws yog XUL, ActiveX, VBScript). Tsis tas li ntawd, muaj cov neeg uas tsis siab integrate nrog lub browser. Nws Silverlight, Nyem, Java. Tam sim no muaj ib tug zoo kev loj hlob ntawm no technology, thiab JavaScript ntsiab yog raug tsim 2.

Lwm hom lus programmmirovaniya

Nws yog hais tias JavaScript xwb. Nyob rau hauv cov ntaub ntawv no, yuav pab rau cov nram qab no programming lus.

Java

Qhov tseem siv lus - Java. Nrog kev pab los ntawm cov lus piav los ntawm txoj algorithms, tab sis nws tsis yog ib txwm yuav tsum tau rau ib tug pa website. Vim li no, lub sij hawm ntev mus download tau java-applet`y thiab muaj ib tug txiav txim npaum li cas.

flash

Los ntawm thaum pib, cov lus ntawm Flash twb tsim raws li ib tug ntoo khaub lig-brazuerny thiab tsim multimedia khoom. Piv txwv li, los tsim kev sib tham sib chaw online, ua si, banners, players rau audio thiab video. Ntawm lwm yam, siv Flash los ua ib tug ntsawb (network kev twb kev txuas), koj muaj peev xwm ua hauj lwm nrog rau hauv xov xwm, khaws cov khoom uas yuav tsis tau xa kev thov mus rau lub neeg rau zaub mov. Muaj yog ib tug yooj yim graphical kev loj hlob cov cuab yeej rau Flash.

Yog hais tias peb los sib piv cov shortcomings ntawm Flash thiab JavaScript, uas cov khoom yog sib txawv heev, lub ntsiab disadvantage ntawm Flash yog nws pluag indexing los ntawm kev tshawb fawb xyaw. Qhov no yog vim hais tias kev tshawb fawb xyaw mus rau kev mus Html. Tsis tas li ntawd muaj yog tsis muaj peev xwm mus xaiv cov ntawv nyeem uas yog nyob rau hauv Flash thawv.

Silverlight, Vbscript, JavaFX, XUL

Los txuam rau JavaScript tuition thaum lub tsev interfaces thiab kev sib txuas lus, kev siv cov Silverlight technology, Vbscript, JavaFX, XUL.
Lawv yog siv tseem ntau tsis tshua tshaj li eeb thiab JavaScript. Mus rau ntsiab lub yam ntxwv ntawm txhua tus ntawm lawv muaj peev xwm hais tias cov nram qab no:

- XUL - siv nyob rau hauv qhov kev piav qhia ntawm desktop daim ntawv sau npe thiab interfaces. Tab sis nws yog ua tau xwb nyob rau hauv cov ntaub ntawv ntawm ib qho kev pab los ntawm Mozilla.

- JavaFX - tsuas yog ua hauj lwm rau ib lub computer nrog Java, vim hais tias nws yog nyob rau hauv tas li ntawd cov lus.

- Vbscript - yog tsim los ntawm Microsoft. Nws tau txais kev pab raws li lub hauv paus rau Visual Basic. Qhov no lus tsis tsim nyob rau hauv txhua txoj kev, nyob rau hauv cov hnub yog tsis yog puas tau siv, nyob ntawm seb ib tug tawm los JavaScript.

Silverlight - yog tsim los ntawm Microsoft raws li ib tug competitor rau Flash. Nws kuj tsis muaj npaum li cas tej chaw txij li thaum JavaScript cov hlua yuav muab ntau npaum li cas tshaj ib daim ntawv rau tsab ntawv.

Yuav ua li cas los pab kom JavaScript li cas thiab lub JavaScript kev ua yuam kev

Tam sim no nws yog tsim nyog los sib tham txog txhua hnub muaj teeb meem ntawm cov neeg siv ntawm lub network. Niaj hnub no, ntau thiab ntau ntau nws tshwm sim hais tias tus neeg siv tom qab mus xyuas nws page nyob rau hauv cov kev sib raug. network pom rau hauv lub Upper qhov rais ib qho yuam kev cov lus "JavaScript yog tsis enabled", "Rau kom lag luam ntawm lub site pab kom JavaScript», «JavaScript kev ua yuam kev». Yuav ua li cas mus kho tau nws - ib tug loj heev teeb meem, vim hais tias thaum muaj teeb meem nrog loading video thiab yees duab ntawm tus neeg siv.

Yuav ua li cas kuv pab kom JavaScript nyob rau hauv Mozilla Firefox

Yog hais tias tus neeg siv ua hauj lwm nyob rau hauv lub Mozilla, koj yuav tsum mus rau "cov cuab yeej rau", ces mus rau "tej chaw". Ces, rau lub tab "txheem" koj yuav tsum zuam lub thawv cim "Siv JavaScript".

Raws li JavaScript yog muaj nyob rau hauv Google Chrom

Yuav kom pab los yog lov tes taw JavaScript nyob rau hauv lub browser Cov nram qab no txoj kev yuav tsum tau :. "Teem tau thiab tswj Google Chrom", "tej chaw", "Advanced", "Tej ntaub ntawv (qhov chaw txheem)", "JavaScript" Cia tag nrho cov qhov chaw siv JavaScript (pom zoo).

Yuav ua li cas kuv pab kom JavaScript nyob rau hauv Opera

Yuav kom pab los yog lov tes taw JavaScript nyob rau hauv lub browser yuav tsum tau ua cov nram qab:

- Nias lub F12 tseem ceeb.

- Xaiv cov kev xaiv "Pab kom JavaScript".

Raws li JavaScript yog muaj nyob rau hauv lub IE ( "Internet Explorer")

Yuav kom pab los yog lov tes taw JavaScript nyob rau hauv "Internet Explorer", koj xav kom ua raws li nram no: "cov cuab yeej rau", "Internet Options", "Security" tab, "Xaiv ib cheeb tsam hauv Internet", "Kev cai Theem" khawm, xaiv "scenarios", "Cia nws scripts."

JavaScript nyob rau hauv VC

Tsis tshua muaj neeg nrov nyob rau hauv lub CIS kev network "Vkontakte" nquag pib surprises. Qhia, cov neeg siv "Vkontakte" yws txog cov tsis muaj peev xwm mus mloog lub suab, los yog lub cev tsis mus saib cov video.

Yuav kom daws tau qhov teeb meem no yuav tsum tau JavaScript yuam kev kho nyob rau hauv lub network "Vkontakte".

Yuav ua li cas yog JavaScript VK yuam kev?

Ib tug neeg siv tau mus xyuas ib daim ntawv rau ntawm lub social network thiab sim mus pib ib lub video los yog audio cov ntaub ntawv, tab sis, ces nyob rau hauv lub Upper rau sab laug ces kaum ntawm lub inscription «JavaScript kev ua yuam kev: initAddMedia tsis txhais». Qhov no cov lus zoo nkaus li thaum muaj ib tug ua yuam kev
«[Tshem tawm] initAddMedia».

Txoj kev los daws kom tau qhov teeb meem nrog ib tug yuam kev nyob rau hauv lub social network "Vkontakte":

- Ua ntej no, koj xav mus rau "Start", "Kuv Computer" nplaub tshev thiab lub qhov rais. Ces dhia rau hauv seem nyob rau hauv lub system32 nplaub tshev tsav tsheb. Ces nyob rau hauv daim nplaub tshev thiab lwm yam

- Nyob rau hauv nruab nrab ntawm ib tug me me muaj pes tsawg tus ntawm cov ntaub ntawv nyob rau hauv daim nplaub tshev koj xav xaiv lub hom ntaub ntawv.
Ces cov ntaub ntawv yog qhib siv lub "Notepad". Nws zoo li no: nyob rau hauv lub hom ntaub ntawv koj yuav tsum nias rau txoj kev nas khawm thiab xaiv "Qhib Nrog." Ces koj yuav xaiv cov "phau ntawv Editor WordPad».

Tom qab qhib cov ntaub ntawv koj xav mus saib nyob rau cov ntaub ntawv nrog ib cov ntaub ntawv ntawm 127.0.0.1 localhost. Muaj lwm yam nkag superfluous thiab tsuas yog tabkaum thiab thaiv lub ruaj khov lag luam los ntawm cov suab thiab video ntaub ntawv. Nws yog tsim nyog los kiag li tshem tag nrho cov ntaub ntawv los ntawm cov ntaub ntawv thiab luam tsuas yog tus inscription 127.0.0.1 localhost. Tom ntej no, koj yuav tsum nias "Txuag" thiab pib dua koj lub computer. Thaum "Vkontakte" page tom ntej mus ntsib txhua yam yuav ua hauj lwm zoo.