JavaScript: mahi mahi. JS reo Papatono

Ngaahi Fakakaukau ihirangi hihiri ki te hanga i web-RAUEMI kua riro te täkupu. whārangi pateko me te hoahoa tātauira Tukutuku hopea oti ratou misioni.

Heoi, e kore e hou tukutuku-rauemi i ki kia māngai e te huinga o whārangi hangaia e te tūmau me te tāmata i te pūtirotiro (JS + AJAX).

pupuru e hāngai ana-Tukutuku i te kau o te taenga o te manuhiri e taea kia o taitara e rua mo te record, etahi kuputuhi i roto i te «matenga», he torutoru ngā rārangi o te waehere i roto i te «tinana» me katoa. Ko te toenga o "hapu" i roto i te tukanga o te manuhiri - he reira he pae pai, ranei tuhi ki kia kotahi.

A tuu i te whakaahuatanga, me te āhua o ngā mahi

опыт, наработаный многими десятилетиями. JavaScript - te reira he tekau tau wheako narabotany. He he hītori nui o te whanaketanga, hou rōpū tohu kaihanga ngā. pai Reo whakaaro i roto i, pono, ataahua, me te homai he faingamālie tūturu mō ki ngā tuhituhi waehere mo te tika, me te whaiaro-whakapai ake.

Ko te ariā o te hātepe ko te mahi i konei e kore e tīariari i roto i te parau tumu. O te akoranga, ka taea e te kaiwhakawhanake ki hea i te whārangi ki te whakauru waehere hōtuhi kia hoatu ki roto i te reira, a ka mahi i te reira. страницы? Ko te aha te mea te wāhi i roto i te waehere, e mahi nei te kotahi anake: ka uta (reloading) te whārangi? Te reira taea ki te whakaturia te uara tuatahi o te mea i ētahi taurangi iti.

Hōtuhi - tenei wahi ko te whakaahuatanga matau o taurangi me mahi, pai atu i te wahi pai o te waehere tuhituhi mo tona whakaaro ake. Ko reira mea faufaa, me te nui, he huinga o ngā mahi, pea - o ratou hononga hāngai tahi, engari atu maha te reira rerekē. e kore ko te mea kotahi whakaahuatanga Place o te mahi, me te wahi o tona tono.

Ehara i te mea e tika ana e ka karanga i te mahi i tetahi atu mahi tika, engari e taea te mahi i te reira autaki i roto i te hanganga o te waehere hihiri. He manuhiri e te whakatau i roto i tenei waehere me te mahi mahi pūnaha tino rerekē.

akiaki mahi

akiaki Taumahi - he kore noa me kore kia nui kawenga whakaritea ki huānga whārangi he mahi e hanga i nga mea timatanga o te whārangi, me o nga kawenga tonu, rawa, ka taea e te huri.

Ko te mahi e wahi i runga i te whārangi, i runga i nga mea timatanga, me te whanonga manuhiri ki runga i te reira rānei. Movement o te kiore, papapātuhi, pātene, pakō, ngā, tūemi me ētahi atu huru arahi ki te whakarewatanga o nga mahi e tika ana.

Tuatahi i reira he kore ōrite, me te reira he kahore whakarara. He he he whakautu tika ki te ngā tukutuku-rauemi. Kia pehea te faatupu nohopuku JavaScript te mahi ngā tei reira ki runga maha hangarau (rorohiko, rārangi kōrero), me te pū (arorau hātepe, rohe kaupapa, te tikanga i te raruraru) āhuatanga.

I roto i te meka e taea te tohe i te reira e kua mahi te tahi mea i roto i te whakarara, engari ka tahuri te tahi mea i muri i te tahi mea, engari e kore ko te tikanga o tenei motuhake. He mea nui kia te mahi JavaScript - ko reira he faingamālie ki te hanga i tētahi whakautu tika ki te mahi o te manuhiri.

Tenei whakaaro hou i roto i te hoahoa: tohaina tukatuka i te hohonu o te pūtirotiro kotahi!

Ko te wetereo mō taurangi me mahi

JavaScript-taurangi e whakanohoia i roto i te tūtohu «hōtuhi», a i roto i te tinana o te mahi. E tautuhia Taumahi te ara ano. tikanga Motuhake ki te tuhituhi i roto i te mahi i reira he tetahi mahi, engari kia waiho te reira e tika ana mō te ngā take, a ko reira rawa whaitake.

Whakaahuatanga o te mahi te tikanga haamata ki te kupu matua «mahi», aru e tona ingoa, te rārangi o ngā tohenga i roto i te ', wehea e ngā piko, me te tinana mahi i roto i Whītiki.

I roto i tenei tauira, kua whakaahuatia e rua ngā mahi e whakarato AJAX-utu i waenganui i te whārangi, me te tūmau. Tetahi wahi i runga ake scXHR, no te mea e wātea ana i roto i InitXML e rua, a roto WaitReplySC.

Ko te ingoa mahi me te tawhā "mahi"

Kua He kua aroaro te putanga tukutahingakore ka huaina JavaScript-mahi mahi te i muri i te whakautu tūmau. Ko te kupu, te fariiraa i te whakautu i te tūmau, whai WaitReplySC te tūtohu whārangi, whakakiia ana te mōhiohio riro a ai atu mahi, e ai pai te kōkiri i te tono i muri ki te tūmau.

Tenei he mea nui ano hoki ki te mōhio i taua WaitReplySC - he mahi. scXHR.onreadystatechange = WaitReplySC она передается как параметр. Otiia i roto i te rārangi scXHR.onreadystatechange = WaitReplySC te haere te reira rite te tawhā. Tenei mahi whakawhiti tikanga whānui ki ētahi atu mahi rite tawhā. taiapa oka a hoatu ratou ona tawhā (s) - ka te mahi e mahi ana tonu. Kōrerotia e te ingoa anake, pai na te aha. mahi Piiraa ka meinga te tetahi e ka tona ingoa.

Ko te taumahinga whakatinana mā AJAX, taea ki a koe te karanga i te mahi JavaScript roto i te raraunga riro i te tūmau. I roto i te meka, te tuku i te tono ki te tūmau, tetahi ranei te tahi atu āhuatanga kia kore "mohio" i katoa e mahi tahuri ia, a ki te mea kōrero.

mahi i roto i, me tona hua

Ko te tinana o te mahi, ka taea e koe te tuhituhi i tetahi ngā reo, e, i roto i te meka, tikanga hoki reira te. āhuatanga roto E i whakaatu roto me waho taurangi, engari e kore te hunga e e whakaahuatia i roto i te tahi atu mahi.

Ki te hiahia koe te mahi ki te hoki i te hua, ka taea e koe te whakamahi i te tauākī hoki JavaScript: hoki mai. Ko te tinana o te mahi kia waiho he maha rawaka o ngā tauākī hoki. Ehara i te mea e tika ana e ka hoki katoa o ratou te hua o te momo kotahi.

Tikanga, E wehi ngā tenei faingamālie me, i runga i te āhuatanga rānei, whakatau ki te haere atu i te mahi, no ka taea.

Ehara i te mea e tika ana ki te rere i roto i te hātepe katoa o ngā mahi, ina taea te tiki e koe i roto i mua.

tohenga taumahi

E haere Tohenga ki te rārangi mahi, wehea e ngā piko, E kopakia ana i roto i te ', a ka he i muri i tika tona ingoa. whakamahia nga tohenga ingoa tāupe, ko koutou e taea e haere tika uara. Hei haere te mahi JavaScript i roto i te mahi, me tika koe ki te tautuhi i tona ingoa, kahore taiapa.

Roto te mahi he e wātea ana tohenga tāupe, e kua he taonga roa. Ka taea e koe te kōrero ki tetahi mahi tautohe i roto i ngā tohenga [0], tohenga [1], ... ki te tautohetohe whakamutunga [arguments.length-1].

Te huri i te mahi o te tautohe ko tino i roto i te mahi, engari e kore e ki waho i te reira. I roto i te tikanga ki te huri i te tahi mea i waho te mahi, me te whakamahi i te operator JavaScript hoki, i roto i nei haere te uara e hiahiatia ana ki te waho.

I muri i te mahi mutu, ka katoa i i pā ana ki tona whakatinanatanga, kia ngaro. I roto i te mahia o te mahi kia huri i te taurangi waho, ki te kahore te hunga e kua whakaahuatia i roto i te tahi atu mahi, tae atu te hunga i roto i te roto.

E tatou tohenga callee taonga, tikanga nei ki te karanga i te mahi whakamana e te i te wa i homai. Ki te te take ano, ka whakatinana i te putanga JavaScript o te mahi i roto i te mahi recursion.

Mā te mahi

Ko te āwangawanga matua o nga mahi - ki te mahi ki te pūtirotiro takahanga. Ki te mahi i tenei tata tūtohu katoa kua te kaha ki te tautuhi i te ingoa hui me te mahi o tona ahumahi. Ka taea e koe te whakapūtā ngā maha, engari tohua ia takahanga te kotahi anake te mahi.

Ka taea e tetahi mahi hapai i huānga whārangi maha me te ngā torutoru. Na roto i «tenei» kōwhiringa, ka taea e koe te whakawhiti i te mahi ngā mōhiohio wahi i huaina ai.

Ko te whakamahi matarohia o JS-mahi - te kawenga kaupapa i runga i te āhuatanga. I roto i tenei tauira scfWecomeGo () huaina mahi scfWelcomeCancel ranei () i roto i te puka tāuru / tāputa o te manuhiri, a ka tīpako i te aratau whakahaere scfMenuItemClick (tenei).

I roto i te take whakamutunga, ki te tawhā haere «tenei», e taea ai e koe te ako fakaemana i te mea he diva i huaina. Mau, Kei te pera qualitatively tanuhia i JavaScript i te DOM, a kei te pera wa reira taea ki a koe te whakatere ona āhuatanga, ki te kohikohi i te mōhiohio e tika ana e noa e taea te akiaki whārangi kia ohorere.

E kore e te mahi i ki hoki te string, maha, ranei te tahi atu mahi. Ka taea e hoki te reira i te tonu HTML-huānga, a i te mea te maha e hiahiatia o ngā huānga, me o ratou kawenga, ratou ngā.

Na roto i te whakatakoto i te huānga i te whārangi, hangaia e te kaiwhakawhanake i te taumahinga hou e he pai i roto i ngā o whakaoti te raruraru, me te whakatau i nga ngākau nuitanga o te manuhiri, engari rawa uaua i roto i ngā o te whakatinanatanga.

Mai te whanaketanga o taua he tino mahi, ngāwari ki te kia ngaro i roto i te waehere taketake, i roto i ngā waea mahi, i roto i taime ka hanga e ranei e te ihirangi o tetahi ranei tetahi o te whārangi. I mua i te tango i te aronga taua o te whanaketanga, e whakawarea i te pauna pai nga mea katoa.

I runga i te tohatoha o te whakaaro

kua ki whakaaro i te taumata o nga āhuatanga katoa o te whārangi, i ngā kaupapa katoa, a ka whai i te mārama whakaaturanga o te āhua o mau tupu katoa te kaiwhakawhanake. He uaua te reira, engari ko te mahi he utu reira.

I roto i te JavaScript, kia roa te mahi tae noa ki etahi hui, a he tokomaha kia taua āhuatanga, me ngā kaupapa i te haafifi i ki horahia me tiki ki te "ao o aritanga" o te ngā pūtukatuka.

I roto i tenei tauira, tetahi wahi i mua huaina te mahi i, i tīmataria i te tūemi tahua navigation kōnae. Kei te riro te reira i whakararangi, e ko i te matapihi tika whitu kōnae, e taea te nekehia atu, ka tukatuka. Taea e whakangaueuetia rite te kōnae mā te pāwhiri i runga i te rarangi, me nga mau taviri pere me poraka o whitu nga rarangi.

I roto i ia take he ona ake mahi. I roto i te mau parau te tahi atu, i roto i tenei tauira ohie, e hiahia ana koe ki te tuhituhi o pinepine o ngā āhuatanga e ka tauhohe ki ngā takahanga i te tokorua, me etahi o enei mahi ka hapai i te momo o ngā kōwhiringa me ngā āhuatanga e i kore no te mau ohipa.

Hei tauira, ka tango i te rārangi raro me ngā upwardly. Tenei ka rapua e rānei hanga i tētahi kōwhiringa hou e matarohia a mārama he rauemi, ki te tatau rārangi, te whakamahi i te mahi javascript i runga i te ngohi, me te ki te whakatutuki i te whāinga huatau ranei.

Ko te tautohetohe me ngā hua o ngā mahi

JavaScript taea ki a koe kawe waehere ki te tūnga "tonu-ngā". Nuinga, ka te tautohe o te mahi ko te mahi. kōwhiringa Whakaaetia, hoki te mahi he mahi. e JavaScript reira rawa marie.

Ko te tikanga pai, engari uaua i roto i te pā ana ki te whakatinanatanga tenei. Tū whakaaetia semantically whakarato "mahi" arorau tuku noa e te kaiwhakawhanake tohu.

A, no te he taumahi JavaScript i roto i te mahi - tika katoa, engari ka mahia e te mahi he mahi, a e tetahi, ko te tino uaua ki te whai i te arorau. I roto i te meka, e kore ko te pātai mehemea ki te tono i te pūkenga, i te pātai, ko te ki te whiwhi hua haumaru, me te tika.

He mārama, me te ngāwari kaiwhakawhanake tiaki. He he he raruraru, e hiahia ana koe he otinga, e kore te bug rite «hapa JavaScript te mahi he pāhekeheke» , te mata pātea, mutu engine pūtirotiro katoa ranei.

Ki te ko te mahi, na te kaiwhakawhanake ki te haere i te tāupe ki ngā āhuatanga motuhake o te tautohe, e kore te mea e he tau, e kore te string, e kore te ahanoa. Ko te whakamahi o te tautohe taua taea arahi ki te meka e huri i te taurangi waho, me te ko te hua o te mahi mahi. Tei runga i te huringa e ka tika whakawhitia.

Tuhinga o waehere hanga

Whakatinana waehere mahi hangaia i roto i te akoranga o te mahi atu waehere, he reira taea e te tikanga o «eval». E kore te mea i whakaaro ki te waiho i te otinga pai, engari maha e kore e taea e haafifi i te waehere ki ngā mahi faufaa, a ki te whakawhāiti i te hanganga o te raina mama o JavaScript waehere me te mahia noa te reira.

I roto i tenei tauira, i hanga te whakauru te tuitui ki Tauoti operable etahi mōhiohio. Diva me ihirangi mōhiohio mō te maha rerekē o ngā tūranga rerekē, no te mea e kore e he whakatau taua i roto i tenei āhuatanga whakarato i tētahi āhuatanga kī «javascript hapa te mahi he pāhekeheke» , engari hoatu mau te pānga e hiahiatia ana.

Mita JavaScript tauira neke "mahi i roto i te mahi"

Ki te taea e koe, kahore nga humehume, he pai ki te whakamahi i te reira. He pai katoa o enei kōwhiringa. O te akoranga, i roto i te maha ngā take, he mea te otinga anake.

He tauira matarohia o recursion: te whakarea. He mea uaua nui ki te tuhituhi i tētahi hātepe e ka koropiko, engari he reira tino māmā, ka taea e koe pana i te uara kōpaki. Kei te tipu haere nohopuku rawa whakarea.

Heoi, karanga recursion, me mahi i tetahi atu mahi, e taea te hanga hokiwaea mōhio - mea noa.

Hei tauira, he tepu auau. pea te atu tepu te tepu. e kore e taea te whāiti kōhanga. Tuhia hoki ia tepu ona huinga ake o ngā āhuatanga - rawa nui papai.

He maha peheé tauira, a ka waiho tenei katoa he raruraru tūturu me akina, e kore hoki o te hōtaka. Ko Ko te aha te raruraru e takoto i roto i te meka e kore e whakaturia e kore-humehume ake he pūnaha o ngā mahi, atu ïa, tona patuiro me te mahi pono muri riro JavaScript tiaki, me Developer.