JS foreach injongosenzi lwalo

JavaScript kwezivakalisi inikeza ikhono ukudibanisa izinto zibe kwimiboniso kunye izinto. Ukufikelela izinto zingafumaneka nge nezalathiso kunye namagama ngokusebenzisa abanini komjikelo.

Kodwa ke akusoloko kusenzeka ukuba ukwazi inani leziqalelo yokuqokelelwa ngexesha design kwaye akusoloko kulula ukusebenzisa lwesivakalisi olunikiweyo semantics ngaphakathi kubo.

design Classic

Ingxelo loop Eqhelekileyo "kuba (var i = 0; i

var i = 0;
ngexesha {... aData [i] (typeof aData [i] = 'ayicacisiswanga'!); ... i ++; }

xa inani lweziqalelo ayaziwa.

Unako kwakhona ukwakha ubuchule ezahlukeneyo ukuze zizaliswe kunye processing uluhlu, kodwa zibelula ukusebenzisa, Ukrainian lunee ntlobo ezintsha mihla ngakumbi.

Classic kuhle xa ufuna ukwenza i HR emibuzo (ifani, igama lokuqala, isikhundla), amakhadi yezixhobo (imodeli, umenzi, umthengisi, umhla yentengiso), kunye nezinye data nto ngokokwakheka ukutshintsha kwaye bamele umdla lonyuselo.

Xa element uluhlu lulodwa into okanye isakhiwo oluthixo iimpawu zayo nendlela, abakwazi ukumelana nokutshintsha okubalaseleyo ngobuninzi kunye nomgangatho, kwaye uthatha uluhlu intsingiselo eyahlukileyo.

Foreach loop

Okuhambisa yi iipropati kubalulekile ngqo nokubonakaliswa uluhlu element. Design JS uluhlu foreach, ezahlukeneyo ngandlel ukusuka njengesiqhelo (yamkelwa kwezinye iilwimi), uguqulelo, likuvumela ukuba ukunikezela uluhlu lwe ithuba lokubonisa iimpawu zabo komhla element yakhe.

Masithi omnye uluhlu iquka indlela (iimpawu zabo ubunjani kunye nobungakanani), kunye nenye uluhlu - izithuthi ezihamba kuphela kwiindlela ezithile kwaye kwamatanki ezahlukeneyo amafutha volume, ngamanye umgama phakathi izithako nako kubalulekile.

Kwimeko ngobuwena loo algorithm efanelekileyo kufuneka athathe njengesiseko, umzekelo, indlela uze ukhethe iimoto eziza kukwazi ukuqhuba kuyo. Kwaye ke kungcono, ukuba endleleni kunye nemoto, ethetha kule program njengezinto, "abazifumana bekuzo." Esi sicelo ngokwendalo into ebomini lwenkqubo, leyo, phakathi kwezinye izinto, akuyomfuneko ukutshintsha yotsalo ukutshintsha indlela kunye nemoto ingqokelela, ngokuzenzekelayo ihlawula wokulungisa indlela, ukugcinwa imoto njalo

Nngokobuchwepheshe e JS isakhiwo foreach ilula kakhulu: "aData.forEach (fData);", apho fData - umsebenzi oluthi lusetyenziswe isiqalelo ngasinye uluhlu aData:

ukusebenza fData (ixabiso, isalathiso) {sText + = index + '=' + ixabiso + '; '; }.

Ukuba idatha engumthombo umelwe ngolu hlobo lulandelayo:

var aData = [1,2,3,4];
aData.push (11);
aData.push (22);
aData.push (44);
aData.push ( 'umgca 1');
aData.push ( 'umgca 2');

var sText = '',

ngenxa yokusetyenziswa enjalo JS foreach uya:

"0 = 1 1 = 2 2 = 3 3 = 4 4 = 11; 5 = 22, 6 = 44, 7 = umgca 1, 8 = 2;".

Iimpawu izinto Array

Into JavaScript - okhethekileyo. Ukusebenzisa izinto kule ulwimi yahluke kakhulu ukusuka Ukusetyenziswa kwezinye iilwimi. Into - oku kukodwa liyindlela yobeko zemihlaba kunye neendlela. Xa kunjalo okunene ukwenza intshukumo, ukonga okanye uhlela umxholo okanye ezinye zangaphandle izinto, kwimiboniso, variables.

Izinto esiza uluhlu njengoko kwizakhelo kwi filmstrip, xa ukuphindwaphindwa e-JS izakhiwo foreach into zenze semantics ezintsha: ukuyila ingqiqo bume.

Ngoko ke, indlela bebodwa uyakwazi ukukhetha imoto ukuze ndikhwele kubo, kwaye ngomhla wokugqibela luhluzwa iindlela ezikhoyo. Ukuba akuyihlawuli ingqalelo, ukuba komsebenzi kule khetho lokuprograma ngakumbi ikhowudi oluthembekileyo, lo msebenzi - ukuze ubone indlela eya lonikezelo - yenza JS foreach ukwakha kwi isisombululo enentsingiselo ilula: ukwandisa iindlela zeendlela, khetha umatshini aze aphumeze ukuziswa kwempahla.

Ukuba iindlela, iindlela kunye noomatshini - lens izinto, le algorithm lula kakhulu. Isenokuba kubonakale zasemzini ukuba ukuvela JS isakhiwo foreach njengokuba ixesha elide ukuza. Noko ke, nangona elula yencopho, xa kusenziwa kunzima ukuphumeza.

Zinyamekele JS foreach kunye real izinto

Sicinga developer mihla isebenza izinto eziqhelekileyo program, kodwa hayi izinto le ngxaki. Hayi ngokuqhelekileyo ziqondwa ngabo emotweni wendlela, indlela, umgama ...

isinxulumanisi senkqubo into ebomini uye savela iindlela sameva, kwaye ke ngokwesiqhelo kuye kuthathwe ukuba ukudala uluhlu inkqubo into, iifomu, amaqhosha, ibhokisi yokhetho indlela, njalo njalo

Ukongeza, JS foreach kunye nezinye uyakha ulwimi lwenziwa ibhrawuza umtyeleli ukuba ungenisa ukulinganiselwa ezinkulu practice. Ayizizo zonke umphuhlisi ilungele ukwabelana ikhowudi yayo. imizekelo ngempumelelo ukusetyenziswa amaqoqo kunye ingqokelela yezinto real - indlela elungileyo ukuphucula ulwazi.

Nangona kunjalo, ubukho ikhowudi JavaScript ukusetyenziswa developer obelungacetywanga kunefuthe ngqo kuphuhliso izimvo ezithembisayo ukuba izinto obuluqilima kunye real-ihlabathi. JS ukwakhiwa foreach ayikho kodwa egqibeleleyo, kwaye libonakala uphuhliso semantics babo ukuze babe ulwalathiso ethembisa kakhulu.