Preprocessor CSS: Uhlolojikelele, ukukhethwa, isicelo

Kasibili zonke nabaqambi bamawebhu abanolwazi ukusebenzisa preprocessor. Azikho okuhlukile. Uma ufuna ukuphumelela kulo msebenzi, ungakhohlwa ngalezi zinhlelo. Uma uthi nhlá, bangase kubangele horror imfundamakhwela ethule - ke kufana kakhulu izinhlelo! Empeleni, ungakwazi ukubhekana zonke izici CSS preprocessor cishe ngosuku, futhi uma uzama ke kwamahora ambalwa. Esikhathini esizayo, bayoba kakhulu ukuphila kwakho kube lula.

Kanjani CSS preprocessor

Ukuze uqonde kangcono izimfanelo lobu buchwepheshe, kokubuka kafushane umlando isethulo ezibukwayo of eWeb.

Lapho kuphela nje ungakaqali ukusetshenziswa omkhulu we-Inthanethi, akukho amashidi isitayela wayengekho. Ukwenza amadokhumenti kwakuxhomeke ngokuphelele on isiphequluli. Ngamunye wabo waba izitayela zabo, okuyinto ziye zasetshenziswa ekwelapheni tags ezithile. Ngakho, emakhasini sehluke kuye ngokulandelana isiphequluli ngiwavule. Umphumela - nezinxushunxushu, ukudideka, izinkinga konjiniyela.

Ngo-1994, usosayensi Norwegian Håkon Amanga athuthukile ishidi isitayela engasetshenziswa for ukubukeka emakhasini ngokuhlukile-HTML-mbhalo. Umqondo priglanulas amalungu W3C, ngubani maseko ekupheleni. Eminyakeni embalwa kamuva wanyathelisa inguqulo yokuqala CSS esifakiwe. Wabe lalilokhu ngcono, kuyaphothulwa ... Kodwa umqondo wahlala zonke okufanayo: isitayela isethi ngayinye izakhiwo ezithile.

Ukusebenzisa CSS amatafula bekulokhu kuyinkinga njalo. Ngokwesibonelo, nabaqambi bamawebhu ngokuvamile babenezinkinga ukuhlunga futhi behlukanisa izici, futhi ifa ngisho simple.

Futhi ke kwafika senkulungwane ezimbili. Mshini ngokwethukela laqala ukwenza professional front-end onjiniyela, okuyinto kubalulekile ukuzivumelanisa nezimo futhi ashukumisayo umsebenzi izitayela. Owawukhona ngesikhathi yafuna CSS ticalo ukubekwa kanye ethungatha ukweseka amakhono entsha yesiphequluli. Khona-ke, ngo-JavaScript, kanye ne-Ruby ochwepheshe lashona ibhizinisi, udala preprocessor - superstructure ngoba CSS, izici ezintsha kunezelwa ke.

CSS Wabasaqalayo: izici preprocessor

Sinenkosi imisebenzi eminingana:

• hlanganisa ticalo isiphequluli kanye okhakhi;

• lula-syntax;

• ukunikeza ithuba ukusebenza kubakhethi isichazi ngaphandle amaphutha;

• ukuthuthukisa logic isitayela.

Kafushane: i preprocessor unezela CSS izinhlelo logic amakhono. Manje, isitayela is hhayi lwenziwa kuhlu kokujwayelekile izitayela nge amasu ezilula ezimbalwa futhi izindlela: eziguquguqukayo, imisebenzi, hagfish, imijikelezo izimo. Ngaphezu kwalokho, ikhono lokusebenzisa wezibalo.

Ukubona ukuthandwa lezi add-ins, W3C beqale kancane kancane engeza kungenzeka nabo ikhodi CSS. Ngokwesibonelo, e-sebhithi ngakho lapho umsebenzi, okuyinto osekelwa iziphequluli eziningi calc (). Kulindeleke ukuthi maduze sizokwazi ukusetha eziguquguqukayo bese udala hagfish. Nokho, lokhu kuzokwenzeka esikhathini esizayo esikude, futhi preprocessors kakade lapha kakade ukusebenza kahle.

Popular preprocessors CSS. Sass

Yakhelwe ngo-2007. Ekuqaleni Haml ingxenye - HTML isifanekiso. Izici ezisha izakhi CSS ukulawula Onjiniyela ngaso phezu Ruby on Rails, yona eyaqala ukwenza i wayendlala yonke indawo. I Sass lenqwaba nezici manje ihlanganiswe kunoma iziphi preprocessor: eziguquguqukayo, ukushumeka ka kubakhethi, hagfish (ke, Nokho, lezi zimpikiswano ayikwazi ukwengezwa).

Ukumemezela eziguquguqukayo in Sass

Eziguquguqukayo wamemezela ne $ uphawu. Abakwazi silondoloze izakhiwo zabo lishone, isibonelo: "$ borderSolid: 1px bomvu;". Kulesi sibonelo, thina wamemezela kwenombolo ngokuthi borderSolid futhi lasinda uyayazisa obomvu 1px okuqinile. Manje, uma ku CSS sidinga ukudala umngcele ububanzi ebomvu 1px, umane ubonisa ukuthi variable emva igama lesakhiwo. Ngemva isimemezelo eziguquguqukayo ayikwazi ukushintshwa. Kukhona imisebenzi eminingana esakhelwe ngaphakathi. Ngokwesibonelo, ngazisa kwenombolo nge value of $ redcolor # FF5050. Manje, ikhodi CSS ku izakhiwo noma iyiphi isici, ulisebenzise ukusetha umbala wefonti: p {umbala: $ redColor; }. Ingabe ufuna izame umbala? Sebenzisa umsebenzi mnyama noma ekhanyisa. Lokhu kwenziwa ukuze: p {umbala: mnyama ($ redColor, 20%); }. Ngenxa yalokho, i-redColor umbala kuyoba 20% ukuxegiselwa.

I Sass eziningi imisebenzi esakhelwe ngaphakathi. Worth okungenani uwafunde, kodwa okungcono - ukufunda.

lokushutheka

Ngaphambili, ukuze ukhombise lokushutheka wawudinga ukuba asebenzise i umklamo eside futhi ungakhululekile. Cabanga ukuthi sinesimo div, okuyinto p, futhi-ke, ngesikhathi, setha nobubanzi besandla. Ukuze div, sidinga umbala wefonti obomvu, ngoba p - ophuzi, ngokuba span - pink. Ku-CSS ejwayelekile ke kwakuzokwenzekani kanje:

div {

umbala: obomvu;

}

div p {

umbala: ophuzi;

}

div p span {

umbala: pink;

}

Nge CSS preprocessor zonke kuba lula futhi emfishane:

div {

umbala: obomvu;

p {

umbala: ophuzi;

.span {

umbala: pink;

}

}

}

Elements ngokoqobo "etshaliwe" omunye komunye.

preprocessor iziqondiso

Ukusebenzisa @import iziqondiso ungakwazi ukungenisa amafayela. Ngokwesibonelo, sinalo ifayela fonts.sass ukuthi usho netindlela amafonti. Ixhume ku-style.sass kufayela elikhulu: @import 'amafonti. Uqedile! Esikhundleni ifayela eyodwa enkulu nge izitayela siba ambalwa engasetshenziswa ukuze ufinyelele ngokushesha futhi kulula izakhiwo ezidingekayo.

hagfish

Omunye wemiqondo ezithakazelisayo kakhulu. It ivumela umugqa owodwa ukubuza iqoqo izakhiwo. Usebenza ngendlela elandelayo:

@mixin largeFont {

sefonti umndeni: 'Times New Roman';

usayizi wombhalo: 64px;

umugqa-ukuphakama: 80px;

isisindo sefonti: gqamisa;

}

Hagfish ukusebenzisa kungxenye ekhasini, sebenzisa @include umyalelo. Ngokwesibonelo, sifuna silisebenzise kulowo unhlokweni h1. Sinazo isakhiwo ezilandelayo: H1 {@include: largeFont; }

Zonke izakhiwo hagfish babelwa ingxenye h1.

preprocessor Ngaphansi

Syntax Sass uyakhumbula izinhlelo. Uma ufuna inketho ukuthi kuyinto ekahle Wabasaqalayo ukutadisha CSS, funa emincane. It yadalwa 2009. Isici esiyinhloko - usekelo CSS-syntax bomdabu, ezingajwayelekile ngakho izinhlelo Imposer kuyoba lula ukufunda.

Eziguquguqukayo kuthiwa usebenzisa uphawu @. Ngokwesibonelo: @fontSize: 14px;. imisebenzi yokwakha isidleke ku izimiso ezifanayo e Sass. Hagfish imenyezelwa kanje: .largeFont () {sefonti umndeni: 'Times New Roman'; usayizi wombhalo: 64px; umugqa-ukuphakama: 80px; isisindo sefonti: gqamisa; }. Ukuze uxhume ke akudingekile ukusebenzisa preprocessor iziqondiso - vele ungeze hagfish okudalwe kule izakhiwo element ekhethiwe. Ngokwesibonelo: h1 {.largeFont; }.

Stylus

Enye preprocessor. Wadala ngo-2011 by the author efanayo, lokho kwangenza umhlaba Jade, Express kanye neminye imikhiqizo ewusizo.

Eziguquguqukayo kungenziwa limenyezelwe ngezindlela ezimbili - kungaba ngokuqondile noma ngokuphelele. Ngokwesibonelo: wefonti = 'Times New Roman'; - inketho ngokuphelele. Kodwa $ wefonti = 'Times New Roman' - ecacile. Hagfish kuthiwa washo namazwi ayebonisa axhunyiwe. I-syntax simiswe ngalendlela lelandzelako: redColor () umbala obomvu. Manje singakwazi ukwengeza nto, isibonelo: redColor h1 ().

Stylus ku unganakile kungase kubonakale engaqondakali. Uphi "bomdabu" kubakaki futhi amakhefanangqi? Kodwa kubalulekile ukuba shí ke, zonke kuya kuba sobala kakhulu. Nokho, khumbula ukuthi ukuthuthukiswa eside lokhu preprocessor kungaba "wean" usebenzisa zakudala CSS-syntax. Lokhu ngesinye isikhathi kudala izinkinga nalapho kudingeka asebenze nge 'emsulwa "nesitayela.

Yini preprocessor ukukhetha?

Empeleni, kuba ... akunandaba. Zonke izinguqulo ukunikela mayelana izici ezifanayo nje syntax ngasinye sihlukile. Sincoma ukuqhubeka kanje:

• uma - uMklami futhi ufuna ukusebenza izitayela kokubili khodi, sebenzisa Sass;
• uma - a coder futhi ufuna ukusebenza izitayela njengoba ngesakhiwo ezivamile, sinake Ngaphansi;
• uma uthanda Minimalism, sebenzisa Stylus.

Ukuze zonke okuhlukile inombolo engapheli imitapo ezithakazelisayo okungakusiza nakakhulu lula ukuthuthukiswa. Abasebenzisi Sass Kunconywa ukuba banake Compass - iyithuluzi elinamandla izici eziningi esakhelwe ngaphakathi. Ngokwesibonelo, ngemva kokuba uyifake awusoze kungadingeki nokuba ukhathazeke ngokusho nomthengisi okufushane Isiqalo. Lula ukusebenza nge grid. Kukhona amathuluzi ngokusebenzisana izimbali, sprites. Ububanzi kakade kumenyezelwa hagfish. Nikeza leli thuluzi izinsukwana - ngaleyo ndlela ngeke umsindise isikhathi esiningi nomzamo esizayo.