A ka'ida, kowane gidan yanar gizo an gina shi ne bisa fasahar 3; HTML, CSS da Javascript. HTML yayi ma'amala da odar sassa daban-daban na rukunin yanar gizon, CSS tare da hanyar da aka sanya waɗancan sassan kuma Javascript ayyuka masu rikitarwa kamar amsawa ga ayyukan mai amfani.
En abubuwan da suka gabata Mun bayyana cewa tsarin CSS ne kuma an ba mu kyawawan abubuwan da zamu iya amfani dasu a cikin Linux. Ta yaya rawar Javascript ke da ɗan wahalar bayani, za mu gabatar da wata karamar gabatarwa kan batun, kafin mu yi tsokaci game da tsarinta.
Yaren shirye-shiryen Javascript. Introductionan gabatarwa
Menene Javascript?
Javascript ne - Harshen shirye-shiryen asali an ƙirƙire shi don dakatar da shafukan yanar gizo daga tsaye, kodayake a yau amfani da shi ya bazu zuwa sassan da ba su da alaƙa da yanar gizo.
Lshirye-shiryen da aka rubuta a cikin Javascript ana kiran su rubutun kuma suna gudu a cikin wata na’ura wacce ake kira da injin Javascript.
Duk masu bincike na zamani sun hada da sigar su ta injin Javascript
Don amincin masu amfani, masu bincike daban-daban sun sanya iyaka akan abin da lambar Javascript zata iya yi. Misali, samun dama ga fayiloli masu mahimmanci akan faifai. Koyaya, wannan yana iya ƙara iyakance a cikin zaɓuɓɓukan daidaitawa na kowane ɗayan.
Aikin lambar Javascript a cikin shafin yanar gizo kamar haka:
- Injin Javascript da aka saka a cikin burauzar ya karanta lambar.
- An canza lambar zuwa harshen mashin.
- Injin yana aiwatar da lambar.
Kasancewa yare ne na shirye-shirye, Javascript na iya yin ayyuka kamar waɗannan:
- Adana bayanai a tsakanin masu canji.
- Yi amfani da kirtani na rubutu.
- Gudanar da shirye-shiryen amsawa ga abubuwan kamar danna hanyar haɗi.
Arfin Javascript yana ƙaruwa ta hanyar amfani da Abubuwan Shirye-shiryen Shirye-shiryen Aikace-aikace (APIs)
APIs ne shirin dakunan karatu wanda aka kirkira don takamaiman ayyuka wanda ke 'yantar da mai ci gaba daga sake rubuta lambar data kasance. Game da Javascript zamu iya magana game da nau'ikan APIS guda biyu
Binciken Api
Suna gudu a cikin burauzar kuma suna amsa yanayin. Muna da, misali:
Takardar Takaddun Takaddun aiki (DOM): Yana ba da damar yin gyare-gyare ga lambar HTML da CSS na shafin don amsawa ga wasu abubuwan da suka faru. Wannan shine batun shafukan yanar gizo waɗanda ke ba mu damar ganin yadda shafi zai bayyana akan na'urori daban-daban.
Geolocation APIa: Ana amfani dashi don gano wurin mai amfani da amsawa daidai. Misali, Netflix ne ke amfani dashi don sanin irin abubuwan da zaku iya gani a cikin ƙasarku ko Google Maps don nuna muku inda kuke.
Canvas da WebGL: Sun dace da makircin zane 2d da 3d
APIs na Multimedia: Suna ba da izinin watsawa da karɓar abun cikin multimedia daga shafin yanar gizo.
APIs na uku
Ayyukan yanar gizo daban suna ƙoƙarin samun ƙarin masu amfani (kuma a wasu lokuta ƙarin bayani daga waɗancan masu amfani don siyarwa) Wannan shine dalilin ƙirƙirar hanyoyin musayar shirye-shirye don masu haɓaka su haɗa ayyukan aiki cewa waɗannan ayyukan suna samarwa ga shafukan yanar gizo. Wannan misali misalin waɗannan shafukan yanar gizo ne waɗanda ke ba ku damar yin rijista tare da asusunku na Google ko Facebook.
Yadda lambar Javascript ke aiki a cikin gidan yanar gizo
Da farko dai, dole ne a bayyana hakan kowane rubutun javascript yana gudana a cikin yanayin aikin sa na lokaci. Akwai yanayin aiwatarwa ga kowane shafi (idan muka buɗe shafuka daban-daban a cikin taga ɗaya) ko don windows daban-daban idan muka fi so. Babu wata hujja da suke hulɗa da juna ko, kamar yadda muka ce, tare da tsarin aiki ba tare da sa hannun mai amfani ba.
Na farko se yana loda lambar HTML na shafin yanar gizon kuma an ƙirƙiri samfurin abu na daftarin aiki don a iya nuna shi a cikin burauzar. Abubuwan da za a haɗa su ana ɗora su zuwa shafin azaman kafofin watsa labarai, hotuna, da zanen gado. A ƙarshe, ana sanya salo zuwa sassa daban-daban na shafin kamar yadda aka tsara ta hanyar zanen gado.
Da zarar an gama wannan duka, to lokacin da injin Javascript ya fara aiki bin jerin da aka ambata a sama.
A cikin labarinmu na gaba zamu tafi tare da jerin abubuwan da aka alkawarta don Javascript.