-Javascript Array ukulondoloza esingenamkhawulo lokwehlukile

I-JavaScript - ulimi isiphequluli, ngoba akuzona zonke inkinga idinga eziguquguqukayo ayo, afanayo kanye netintfo. Ezimweni eziningi kwanele nje usebenzise DOM (Document Into Model). Kodwa ngisho nangaphansi kwezimo ezinjalo, incazelo efanele idatha asetshenziswa njalo kwenza uhlelo, intuthuko ephelele okulula ukusetshenziswa futhi okwalandela.

Amagama abalulekile, kodwa, ebhekisela uhlelo izosetshenziselwa futhi ushintsho, kuyafaneleka ukuthi ubeke umkhawulo "idatha" amazwi futhi "eziguquguqukayo". Oh futhi yini bayoba - i-JavaScript Array, Into, noma nje integer - kuncike kuleyo nkinga, noma kunalokho kusuka endaweni ethile kuwo.

Ikhodi logic nedatha

Program esetshenziswa lokuxhaphaza idatha. Kwakukhona futhi namanje kusenjalo ezinye eziguquguqukayo in ezihlukahlukene izethulo (imigqa, izimpawu, izinombolo, izinsuku, ...), njengoba umthetho, afanayo eceleni isebangeni, futhi (mbhangqwana yokugcina emashumini) izinto.

Esikhathini esithile ngesikhathi idatha esiqinile ukuthayipha isibe esifuze, futhi manje ngazo zonke izilimi zanamuhla, lesi Ungashintsha hhayi kuphela okuqukethwe kodwa futhi uhlobo. Okuhle noma okubi, kuzobonakala, kodwa ukuthayipha eqinile inezici yayo omuhle. Nokho, uma kwenzeka, khona-ke, kungani singenakwahlulela "rastipirovat" yonke le nqubo?

Ngamagama semantic, okungukuthi ngaphandle miyalelo, iyiphi variable inenani. Futhi kunoma iyiphi eziyimbangela siyashintsha. Kulandzelana kwalokucuketfwe lokuhleliwe izinguquko - inani ukuthi, ngokuya-JavaScript - elementi afanayo.

Ngamanye amazwi, uma uhlelo unqume ukuba ningazinaki lezi uhlobo variable bafakwa ulimi yokukhathalela ukuguqulwa efanele futhi ifike ngesikhathi ezinhlobo, kungani musa lula: kukhona nje idatha, kanye, ingasaphathwa lokho abayikho endaweni isicelo - inombolo, uchungechunge, uhlu, noma uphikisana - lokho ikhodi ukuxazulula. Okuningi kahle: lokhu kufanele uqobo ukucacisa ukuthi yini ongayenza naso nokuthi.

idatha elula le-syntax

eziguquguqukayo Simple kukhona izinhlobo ezahlukene. Uhlobo ukuguqulwa zenziwa ngokuzenzakalelayo lapho kuphakama isidingo.

Lesi sibonelo uchaza s elula variable, lapho umphumela uzobe enabo-JavaScript Array aCheck. I i variable kuchazwa ngqo umjikelezo wokusebenza aCheck. Lapha, izakhi afanayo (wadala usebenzisa Array push-JavaScript isakhiwo) ukumela amagugu ezintathu izinhlobo ezahlukene. It okukhiphayo umjikelezo wokuqala ilandelana igama uhlobo, kwesibili - amagugu langempela. Uhlobo Ukuguqulwa othomathikhi.

Mayelana enanini lama-elementi kumalungu afanayo

I-JavaScript Array akuyona afanayo associative. Ukufinyelela izinto usebenzisa okhiye zezinombolo, inombolo enkulu izakhi - 2 ^32, kodwa ukuze uzizamele zinciphise isibalo zezinhlamvu izinto akufanele kube.

algorithm muhle njalo inombolo engenzeki Dunn futhi JavaSscript Ubude bohlelo design yethulwa ngo-syntax akuyona ukulawula ivolumu afanayo in umongo elikuqukethe.

aCheck.length yenani akulona njalo inani langempela labantu izakhi. I-JavaScript Array ingaqukatha eziningi nokuthi kukhona uthunyelwe, kodwa ukuthola ncamashi kangakanani, ngezinye izikhathi kufanele bazikhandle.

Kulesi sibonelo, aCheck inkulumo [5] kwandisa ukuba izakhi eziyisithupha afanayo. Uqinisa ithemba lokuthi obuphelele sici uyonika ukubaluleka 4, kalungisiswa.

afanayo associative

Ngokusemthethweni-JavaScript Array kungaba okwejwayelekile, okungukuthi, amalunga ifinyelelwe Inkomba zezinombolo. Kodwa empeleni, ungasebenzisa imiqondo associative.

umsebenzi elula kakhulu futhi ezivamile ukuhlunga imigqa namakholomu etafuleni ingaxazululwa array associative. Point kumbuthano eduze igama kukholamu kusho akukho ekuhlungeni, kuze umcibisholo - ukwehla, phansi umcibisholo - unyuka. Chofoza yokuwohloka ikholomu (inketho realiatsii-JavaScript: Hlunga Array).

Kulesi sibonelo, array elakhiwe cSortCols ukuhlunga izindawo by ikholomu ngayinye (S, C, W, ...). Amanani izinkomba u kuphela, d. Umklamo ngoba kukho konke ligated kumugqa ofanayo (ikhodi ikholomu, futhi isiqondiso ukuhlunga). Lo mjikelezo ubheka zonke izakhi ze-uhlu, bese usebenzisa i-JavaScript Ubude bohlelo umsebenzi akudingekile.

Ukudala afanayo ukuhlunga ku-JavaScript

isipiliyoni Beautiful - bhala 'var xMass = [];' noma 'var yArr = {};'. Esimweni sokuqala, amalungu afanayo evamile izonqunywa, esimweni sesibili - associative. Sebenzisa inketho-JavaScript okusha Array () zingenza, kodwa ngokuvamile lokhu isakhiwo esisetshenziselwa nezinye izinjongo, ikakhulukazi ukusebenza izinto.

Dala i-afanayo, ungakwazi ngokushesha ukugcwalisa eziguquguqukayo, kodwa njengoba umthetho, ukugcwaliswa langempela futhi aphethe afanayo ngamandla, phakathi kokusebenzisa zohlelo. Uma kudingekile, ungasebenzisa ukuhlunga i-JavaScript Uhlobo Array design, engesiyo nezimo kakhulu, kodwa kukuvumela ukuthi ulawule inqubo esebenzisa imisebenzi yayo.

Shayela: arr.sort () kuholela amatafula uphenya ASCII kulandela inqubo. Umsebenzi ephambene - izakhi izinguquko: arr.reverse (). Lokhu umsebenzi eshintsha oda yizakhi afanayo ku reverse.

Kuzo zombili lezi zimo, igama elithi libhekisela Fika afanayo. Esimweni sokuqala bavunyelwe ukusebenzisa ekuhlungeni zabo umsebenzi, ukuthi iyona arr.sort inselele (myfunc (a, b)) kuzoholela ucingo siqu myfuct umsebenzi wakho, okumele ukunikeza umphumela kuye idatha: a futhi b. Uma esimweni esingaphansi yesibili, khona-ke 1, uma kwenzeka okuphambene 1, futhi uma = b bese 0. Lapha ukuqhathanisa umbandela kunqunywa uhlelo kumsebenzi myfunc.

Umqondo we-elementi asebenzayo

Umsebenzi ukubiza enqubeni ukuhlunga, Ungenza izenzo ezahlukene. Ngokombono design, esebenzisa, kungadingeki ukuphendula imingcele okokufaka, futhi umphumela - hhayi izinombolo ezintathu kuphela 1, 1 no 0 kumalungu afanayo kuyafakwa cyclically zonke isici, kungase kabusha afanayo.

Uma sicabange ukuthi afanayo - kuwumuzwa othile, othile isakhiwo idatha, ke Array JavaScript iguqulwe ibe okuqukethwe elibanzi variable.

Uma sithatha njengesisekelo ukusetshenziswa lokuqala noma isici lokugcina behleliwe njengabantu abayakulwa, okuqukethwe kwayo, ukukhishwa umsebenzi uhlobo Ungakwazi ukuguqula array ukuze kungxenye yokugcina kuqala / kuzohluka, njengoba kudingwa yi-nemibandela inkinga.

Lo mbono kungavumela kabusha algorithm izixazululo ngaleyo ndlela, ikakhulukazi, ukuthi asikho isidingo eside ukusebenzisa imiklamo uma () {} enye {} futhi ushintshe () {case '': ...; icala '': ...; ...}.

Ngu balawula okuqukethwe amalungu afanayo, ungahambisa izinto ezingaphakathi, kanjalo ekushintsheni ukusebenza zangaphandle, okuyinto ingatholakala ngokusebenzisa lokuqala noma kungxenye yokugcina.

I-JavaScript wezinhlu: ukusetshenziswa engenangqondo ekwenzekeni

Njalo ulimi muhle ngoba ikuvumela hhayi kuphela ukushintsha isakhiwo kanye nokuqukethwe idatha, kodwa ikhodi yangempela. Umqondo ngokucabangela variable njengenhlangano Abstraction, okusho ekuqaleni ngaphandle kokunikezela isimo salo ejwayelekile, bavula khathizwe entsha.

Kuzoqalwa nge-Abstraction, okuguquguqukayo, afanayo noma into zikuvumela ukuthi uthumele izinto ukucubungula idatha njengoba umsebenzi lezi idatha, kanye Dynamics.

Ngokwesibonelo, ukufunda umbhalo, singakwazi ukuchaza lokhu "umbhalo", okuzokwenza zihlukaniswe zibe isiphakamiso - isivivinyo of 'phuzu' (ngokomongo, okungukuthi, ikhumbula syntax imisho). Iziphakamiso kuphihlizwe zibe imishwana (ngokomongo, comma futhi syntax ezifanele). amazwi Okuningi futhi izincwadi.

Umphumela: ungakwazi ukusebenza umbhalo ezingeni, imisho, amagama. At ngamunye Ezingeni, ungakha umsebenzi "ubunjalo", okuyinto uyobheka efanayo noma fanekiso. Ungakha umsebenzi isicelo nobungako bemisho, nemishwana ukuze nenye idatha.

izinhlelo Modern isikhathi eside akuyona imfundiso engenakuphikiswa, kodwa iqiniso lokuthi kule minyaka eyishumi edlule by isakhiwo syntactic kanye nesipiliyoni wavula khathizwe entsha konjiniyela izilimi okungahlosiwe - kodwa ukuze kutholakale futhi kusetshenziswe.