Preprocessor CSS: Isishwankathelo, ukhetho, isicelo

Ngokupheleleyo zonke abathungi web abanamava ukusebenzisa preprocessor. Akukho nketho. Ukuba ufuna ukuphumelela kulo msebenzi, musa ukulibala ngezi nkqubo. Xa uqala kuqala, ukuze enze ummangaliso abo basandula kuqalisa cwaka - yinto efana kakhulu zokuhlela! Eneneni, unako ukumelana zonke iinkalo CSS preprocessor yangathi yimini, kwaye xa uzama, ngoko ezimbalwa iiyure. Kwixa elizayo, baya kakhulu lula ubomi bakho.

Njani CSS preprocessor

Ukuze siqonde ngcono iimpawu obu bugcisa, ngokufutshane sijonge imbali le ntetho olubonakalayo lamaphepha Web.

Xa kuphela nje iqalile ukusetyenziswa omkhulu we Internet, akukho amakhasi ohlobo yayingekabikho. Ukwenziwa kwamaxwebhu kwakuxhomekeke ngokupheleleyo browser. Ngamnye kubo baba izimbo zabo, eziye zasetyenziswa ukuze unyango tags ezithile. Ngako oko, amaphepha khangela ezahlukileyo ngokuxhomekeke indlela apho isikhangeli uvula kubo. Isiphumo - isiphithiphithi, ukudideka, iingxaki nababhekisi phambili.

Ngowe-1994, isazinzulu Norwegian Håkon Ubuxoki ziphuhlise ishithi lesimbo enokusetyenziswa ukuba imbonakalo amaphepha ngokwahlukileyo ukusuka HTML-uxwebhu. Uluvo priglanulas amalungu W3C, lowo ngoko nangoko waya ukugqitywa. Kwiminyaka embalwa kamva wapapasha inguqulelo yokuqala CSS incazelo. Emva koko waye waphucuka rhoqo, iyagqityezelwa ... Kodwa ingqiqo wahlala yonke enye: indlela nganye ukubeka iimpawu ezithile.

Ukusebenzisa iitafile CSS ibisoloko kuyingxaki. Umzekelo, web abayili ebezikholisa ukuba iingxaki kakuhle yamaqela iimpawu, kunye nelifa akukho ilula kakhulu.

Kwaye ngoko kwafika senkulungwane ezimbini. Iimpawu baya laqala ukwenza abaphuhlisi ekupheleni-ngaphambili zobungcali, nto kubalulekile ukuba izimbo umsebenzi bhetyebhetye kunye neguquguqukayo. Khona ngexesha ifuna izimaphambili CSS nokubekwa kanye kunikwe inkxaso izakhono ezintsha browser. Emva koko, yi JavaScript, kunye neengcali Ruby efika phantsi ishishini, ukudala preprocessor - superstructure ngenxa CSS, iimpawu amatsha esongezwa kuyo.

CSS for Beginners: features preprocessor

Baye imisebenzi ezininzi:

• ezenziwa izimaphambili ibrawuza kunye khaki;

• lula syntax;

• ukunika ithuba lokuba ukusebenza selectors ekwiseli ngaphandle iimpazamo;

• ukuphucula logic wesimeli.

Ngokufutshane: i preprocessor yongeza CSS logic uhlelo ubunakho. Ngoku, wesimeli ayikho lwenziwa kuhlu eqhelekileyo entlobo kunye ne amacebo ezilula ezimbalwa kunye neendlela: variables, imisebenzi, hagfish, imijikelo iimeko. Ukongeza, ukukwazi ukusebenzisa imathematika.

Ukubona ukuthandwa ezi wokongeza i-in, i-W3C baye baqalisa ukongeza ngokuthe ithuba kwabo ikhowudi CSS. Umzekelo, kwi iinkcukacha ukuze Calc () umsebenzi apho, nto leyo ixhaswe bakhangeli beencwadi abaninzi. Kulindeleke ukuba kungekudala kuya kuba lula ukubeka izinto ze udale hagfish. Nangona kunjalo, oku kuya kwenzeka kwixesha elizayo esikude, kunye preprocessors kakade apha kwaye sele ukusebenza kakuhle.

Popular preprocessors CSS. Sass

Yenzelwe ngo-2007. Ekuqaleni isakhi Haml - i HTML template. iimpawu ezintsha beengxenye CSS ukulawula ababhekisi phambili ukomeleza kwi-Ruby on Imizila, eyaqala ukusasaza kuyo yonke indawo. I Sass inani enkulu nezici ezifakwe ngoku nayiphi preprocessor: variables, iyalungisa of selectors, hagfish (ngoko ke, ezi iimpikiswano ayikwazi ukufakwa).

nesebenzayo bamemeze Sass

Nesebenzayo niyathetha uphawu $. Bayakwazi ukugcina iimpawu zazo kunye iiseti, umzekelo: "$ borderSolid: bomvu 1px;". Kulo mzekelo, siye ibhengeze variable ekuthiwa borderSolid ndalisindisa ixabiso ebomvu 1px okuqinileyo. Ngoku, ukuba lo CSS kufuneka ukwenza umda ububanzi obomvu 1px, ibonisa nje ukuba bume emva igama lesakhiwo. Emva kokuba isaziso yezahlukileyo alunako ukutshintshwa. Kukho imisebenzi emininzi eyakhelwe-ngaphakathi. Umzekelo, ukubhengeza variable ezixabisa $ redcolor # FF5050. Ngoku, le CSS ikhowudi kwi iimpawu elementi, sebenzisa yona ukucwangcisa umbala wefonti: p {umbala: $ redColor; }. Ingaba ufuna ukwenza kunye nombala? Sebenzisa umsebenzi mnyama okanye lula. Oku kwenziwa ngenjongo: p {umbala: mnyama ($ redColor,-20%); }. Ngenxa yoko, le redColor umbala iya kuba yi-20% lighter.

I Sass Imisebenzi emininzi eyakhelwe-ngaphakathi. Worth ubuncinane ukuzifunda, kodwa kungcono - ukufunda.

yokwakha

Ngaphambili, ukubonisa yokwakha kwakufuneka usebenzise uyilo elide ubenetloni. Masithi sibe div, apho p, yaye, nayo, wabeka kweminwe. Kuba div, kufuneka ukucwangcisa umbala wefonti obomvu, ngokuba p - otyheli, kuba kweminwe - pink. Xa CSS eqhelekileyo iza kwenziwa ngolu hlobo lulandelayo:

div {

umbala: obomvu;

}

div p {

umbala: yellow;

}

div p span {

umbala: pink;

}

Nge CSS preprocessor yonke kuba lula yaye compact ngakumbi:

div {

umbala: obomvu;

p {

umbala: yellow;

.span {

umbala: pink;

}

}

}

Elements ngokoqobo 'imali' omnye komnye.

imiyalelo preprocessor

Ukusebenzisa imiyalelo import Ungangenisa iifayile. Ngokomzekelo, siye sibe ifayile fonts.sass ukuba ngumlomo uhlobo lobungakanani bamagama. Ixhume ku style.sass engundoqo ifayile: import 'kweefonti i'. Kwenziwe! Endaweni ifayili eyodwa enkulu kunye ngeendlela nabathile ukuba isetyenziselwe unikezelo olukhawulezayo kwaye kulula iimpawu ezifunekayo.

hagfish

Enye i ngcamango umdla. It ivumela umgca omnye ukubuza isethi iipropati. Ukusebenza ngolu hlobo lulandelayo:

@mixin largeFont {

font-ntsapho: 'Times New Roman';

wefonti-size: 64px;

line-ukuphakama: 80px;

font-ubunzima: ngqindilili;

}

Hagfish ukuba isicelo element kwiphepha, sebenzisa @include myalelo. Ngokomzekelo, sifuna ukusebenzisa kwi header h1. Sinawo isakhiwo ilandelayo: H1 {@include: largeFont; }

Zonke iimpawu hagfish ukuba yabela into h1.

preprocessor Ngaphantsi

Isivakalisi Sass ukhumbula kweenkqubo. Ukuba ufuna i khetho ukuba sifaneleke ngakumbi kwabasaqalayo ukufunda CSS, khangela ukuba Less. Oku kwadalwa ngo-2009. Eyona iphambili - inkxaso CSS kwezivakalsi lomthonyama, engayazi loo nto Imposer iinkqubo oko kuya kuba lula ukufunda.

Eziguquguqukayo kuthiwe usebenzisa uphawu @. Umzekelo: @fontSize: 14px;. imisebenzi yokwakha kwi siseko efanayo naleyo echazwe Sass. Hagfish zazisiwe ngolu hlobo lulandelayo: .largeFont () {bomgca-ntsapho: 'Times New Roman'; wefonti-size: 64px; line-ukuphakama: 80px; font-ubunzima: ngqindilili; }. To connect akukho mfuneko ukusebenzisa imiyalelo preprocessor - singadibanisa hagfish ngokutsha kwi iimpawu element ekhethiweyo. Umzekelo: h1 {.largeFont; }.

lokuloba

Enye preprocessor. Yenziwe ngo-2011 yi umbhali efanayo, ukuba banika ihlabathi indlela Jade, Express kunye nezinye iimveliso luncedo.

Ulwahlulo zingabhengezwa ngeendlela ezimbini - mhlawumbi ngokucacileyo okanye ngokupheleleyo. Umzekelo: ifonti = 'Times New Roman'; - ukhetho lokukwekwa. Kodwa $ ifonti = 'Times New Roman' - ecacileyo. Hagfish kuthiwe kwaye ngokupheleleyo iqhagamshele. Le lwesivakalisi yile ilandelayo: redColor () umbala obomvu. Ngoku ungadibanisa esi umba, umzekelo: redColor h1 ();.

Lokuloba on efika kuqala ibonakala iyinto kungenzeka. Uphi kwizibiyeli 'lweenkobe "kunye lokuma phakathi kwezivakalisi lisetyenziswe? Kodwa ke kuyimfuneko ukuba gxwa kuwo, bonke icaca kakhulu. Khumbula, nangona kunjalo, ukuba uphuhliso lwexesha elide le preprocessor nga "uyilumle" usebenzisa le CSS syntax zakudala. Maxa wambi oku kubangela iingxaki xa kokuba ukusebenza nge style "olunyulu".

Yintoni preprocessor ukhetha?

Enyanisweni, kuba ... akunamsebenzi. Zonke iinguqulelo zinika malunga nemisebenzi efanayo nje syntax nganye eyahlukileyo. Siyaleza ukuba maluqhutywe ngolu hlobo:

• ukuba - umdwelisi nkqubo kwaye ufuna ukusebenza kunye nezimbo zombini kwi khowudi, sebenzisa i Sass;
• ukuba - i coder kwaye ufuna ukusebenza kunye nezimbo ngathi ubeko eqhelekileyo, ahlawule ingqalelo Ngaphantsi;
• ukuba uthanda minimalism, sebenzisa Stylus.

Kuba zonke zabo inani elingenasiphelo lamathala eencwadi umdla unako lula ngakumbi nophuhliso. Abasebenzisi Sass Kucetyiswa ukuba anikele ingqalelo Compass - isixhobo esinamandla kunye neempawu emininzi eyakhelwe-ngaphakathi. Ngokomzekelo, emva kokufaka nayo soze ukuba ukhathazeke malunga isimaphambili version umthengisi. Kube lula ukusebenza grid. Kukho izixhobo zokusebenza ngeentyatyambo, sprites. Uluhlu ndisenzile isibhengezo hagfish. Nika le sixhobo iintsuku ezimbalwa - ngaloo ndlela uya konga ixesha kunye nomgudu kwixesha elizayo.