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Txoj kev toArray yog dab tsi hauv Java?
Txoj kev toArray yog dab tsi hauv Java?

Video: Txoj kev toArray yog dab tsi hauv Java?

Video: Txoj kev toArray yog dab tsi hauv Java?
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Cov rauArray () txoj kev yog siv kom tau ib qho array uas muaj tag nrho cov ntsiab lus nyob rau hauv ArrayList khoom nyob rau hauv raws li txoj cai (los ntawm thawj mus rau lub xeem caij). Pob: java ua .util.

Kuj nug, ua li cas koj tig ArrayList rau hauv ib qho array?

Nyob rau hauv luv luv, hloov ib qho ArrayList rau Object array koj yuav tsum:

  1. Tsim ib qho ArrayList tshiab.
  2. Populate arrayList nrog cov ntsiab lus, siv ntxiv (E e) API txoj kev ntawm ArrayList.
  3. Siv toArray() API txoj kev ntawm ArrayList. Txoj kev xa rov qab ib qho array uas muaj tag nrho cov ntsiab lus hauv daim ntawv teev npe no.

Ib sab saum toj no, peb puas tuaj yeem hla array rau Vaarrgs? Yog koj 're dhau ib array rau varargs , thiab koj xav kom nws cov ntsiab lus lees paub tias yog cov lus sib cav ntawm tus kheej, thiab koj kuj yuav tsum tau ntxiv ib qho kev sib cav ntxiv, ces koj tsis muaj kev xaiv tab sis tsim lwm tus array uas accommodates lub ntsiab ntxiv.

Tom qab, lo lus nug yog, dab tsi yog arrays asList?

Cov asList () method of java. siv. Arrays chav kawm yog siv los xa rov qab daim ntawv teev npe tas li rov qab los ntawm qhov teev tseg array . Txoj kev no ua raws li tus choj ntawm array -based thiab sau raws APIs, ua ke nrog Sau.

Koj txheeb qhov ArrayList li cas?

Rau xaiv tus ArrayList , koj tsuas yog yuav tsum hu rau Cov Sau. xaiv () txoj kev hla txoj kev ArrayList khoom populated nrog lub teb chaws npe. Txoj kev no yuav xaiv lub ntsiab (lub teb chaws npe) ntawm lub ArrayList siv natural ordering (alphabetically in ascending order). Wb sau ib co code rau nws.

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