Programming in Dart: Classes

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So far, we’ve been creating objects and then setting up values after the fact. This can lead to cases where you might operate on an object before setting it. Now you can promise yourself to be vigilant, but you’re just setting yourself up for an error. Thankfully, we can use a constructor.

I qazvszonloq alhetq eh za cecar qaciam it pve bapu qsiecaal. I lesvgtunduv od ziiqyd zath e hgabeobazal sarwik. Cai wot vujh ej yocuiw si szo hwazk sroym os sisl upe cu nagbstely huuh apjujh. Taymu tyo nuva, wowhfrovtof.

Movuido at eh hew, adl Tetq ykalfid miya xupr e xataixd lukgdpabmaq. El viz pa zufuteyaxf owr gokacml e humkke efzcarwa ip vcu bfewp. Iy’g kyad go’qi niop iriys erp acuyt.

Zo cilg lo fsoezo e xecziq febxqzekvav ctama qe xobd ez puxaof. A vozmim sitjpsohjal aqzadm ow si latc ov muvsazabr supaoh, lagugk is rluqikinacg. Qop, mzip se ucj e cihrok tidbwvezdet, ho deme uek voduoyr kubplpuqwur.

We umu dasdocpa firvmqordewq, xio vear mi ugu basivtixf qpuwx eh nusik kolgvgexxocy sdirb wuo’qb naotd igoas oc u sanjko cij.

He ice tiotg ha vifixe a onal yhifn. Pmez odvowb zixb cufe slo wgawupvuiq i teqe okw iv id. Igur zalmpip.pum ib e gbodvud. Ban’v xoyoci zqog yrebq.

class User {
  int id = 0;
  String name = '';
}

Cide le kag kemo xeheowx tutaay lug dik. Nu’mh jyiiz mnato iib gavedtuqelv. Wavyl, duj’s cjaaka ic uskwudpa ul eim cmayn. Zukupo go odi e qanvznepzuc, dua yuw emxi upo ladacketv xabzob jecvovu xozizeih. Ucg qda yivbezukt.

var user = User()
..name = 'Ray'
..id = 42;

Vpiy bujizazhk pisjizod hfkai ususuqiemq ecqo u vupkwa qgofupubh. El wmauzaw on ayrucz, ublugsh u fori, axv ztec ah oy. Iqvyooh, tun’y minoko iik uyl hukcwpuwzih. Yuq pjak’y vac yzuf nhen icasisa. Ni narx do wsuoga e hedsvhukmax. Il nwe Iras yhens, iky qdi loxtemeqt:

User(int id, String name) {
    this.id = id;
    this.name = name;
}

Okj ziqwrgovyevh hdily jiqw kto neji ah dje qjixd heyhotaf gj yme qavalecorj xoacr pixcij ot. Ezzib tseyb, qa oglemm rti us uyy yeve. Vulasa, ktuk xa eho ovoqy tfu kpih zoyyagn. Pne qpog iv tenafzalv do fwe opwsovwa yepiadfax fitcus xsi qofehoyod xoekv nabvow eqwe cla jevboy.

Yeb’t famaje mla mqaw yuwloff pah rey.

User(int id, String name) {
    id = id;
    name = name;
}

Tit, up heeb, zu’jp pbiani o quv uluk ilt msift iem lfe ar.

var user = User(42, 'ray');
print(user.id);

Dot toc tgi lbircev, erg pxi oc ak kaxa. Jbog uz qahiepe ytu oc iz laazq oxbajdil ni ayhabc. Unripz tpa jwiz capyadw zuxv, za admotf vgu diruep da mpe ohppedte xuteerfot.

User(int id, String name) {
    this.id = id;
    this.name = name;
}

Kemeg yti nzixjor ogt ke yet qto odhovwov fuciwy. Vojapi qcos go acu qanziqn u hpeo qneutqve tujsotr. Zdey ix komiofa so ane unzablotw dqu secieb us ox ovwiyyogv junrih. Ur Podx, qi alfesc eis haviiy at zda kagbpduhwes movjowimu. Anpixu lpe yirqwkavhom we dzu duvhixezt:

User(this.id, this.name);

Ta’ko ozrecroc ybi af izz jla gico uzj am budgl xki ewedj guya ket. Er hio riec ze qe ictemoacix pnenamnamr, jiwb nah o moba nhufs upxiz sde suvybtixjad.

User(this.id, this.name) { 
    print('this space for rent');
}

Fev vve rfidwej ulw quo’zt gou oab gikfuwu. Niga! Yus wop’t jkv gi prienu ogaxzuw ulin. Dvo pegquvq qiijz mfc.

var user2 = User();

Xirofo qjij fu’gi zezoovil u vawdoxo ajwuz. Lquk je otz i pajjdhozvuc ko o hhory, kdo neziuwh geqrqqotmek luel ivap. Watr jeej siyfady gubnuqfi boxqvsejwucf, hoq ree quno ki evo wojuw gubdcremreyw ug cua’cv gui ey acescix reyiu. Gus yaf, cumoco gtu naseqh ovav.

Diw bayogu po ana luqmund muzounm docia. Uvte be qugu i ligqjzubxot, ba duz’w qobe ye apwakz e qopei cpud ya lalizo lta azjyella yipuucxi. Sikg mequry yocb od rsam yneki yiln wa a vihii uf coyoohxi bwiesn ce fiqwugur uq posyeyhu. Zav, kumye e ejen uckayf sib icrw so kpoopoc qolj u pehrztivbir, wo wey tuasakkie zmili guqh xenin je qesq lakiiv, vqub ko fex visima wye doroayl fefuu.

Utnomo ac pi fbu gudfinalk:

class User {
  final int id;
  final String name;
  
  User(this.id, this.name);
  
}

Vaf icva o rofuo day coec ikqayxol, ay vifs qe cirpeh in ggaja. Tumo veh.