Dab tsi yog char siv rau hauv C ++?
Dab tsi yog char siv rau hauv C ++?

Video: Dab tsi yog char siv rau hauv C ++?

Video: Dab tsi yog char siv rau hauv C ++?
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Cov ntawv luv char yog siv raws li tau txais cov ntsiab lus tseem ceeb hauv qee hom lus programming, xws li C , C ++, C#, thiab Java. Nws yog luv rau tus cwj pwm , uas yog hom ntaub ntawv uas tuav ib qho tus cwj pwm (ntawv, naj npawb, thiab lwm yam) ntawm cov ntaub ntawv. Piv txwv li, tus nqi ntawm a char variable tuaj yeem yog ib qho tus cwj pwm tus nqi, xws li 'A', '4', lossis'#'.

Xav txog qhov no, dab tsi yog qhov txiav tawm tus cwj pwm hauv C ++?

Luv teb: a null xaus hlua is a char array nrog tus nqi null (0x00) tom qab siv tau kawg tus cwj pwm hauv txoj hlua. Lus Teb Ntev: Ib txoj hlua yooj yim hauv C lossis C++ (tsis muaj STL) tsuas yog ib qho array ntawm cov cim . char myString[25]; Nyob rau lub sijhawm no, peb tsis muaj lub tswv yim dab tsi nyob hauv txoj hlua ntawd.

Ib yam li ntawd, char data type yog dab tsi? Cov CHAR data type . Cov CHAR data type khw muag khoom cim cov ntaub ntawv nyob rau hauv ib tug ruaj-ntev teb. Cov ntaub ntawv tuaj yeem yog ib txoj hlua ntawm ib-byte lossis multibyte cov tsiaj ntawv, lej, thiab lwm cov cim uas tau txais kev txhawb nqa los ntawm cov cai teev ntawm koj qhov chaw database. Koj tuaj yeem sau ib-byte lossis multibyte cim hauv a CHAR kab.

Ib yam li ntawd, nws tau nug, qhov txawv ntawm char thiab hlua hauv C ++ yog dab tsi?

A txoj hlua yog ib chav kawm uas muaj a char array, tab sis cia li tswj nws rau koj. C++ strings cancontain embedded cim, paub lawv ntev yam tsis suav, yog ceev tshaj heap-xav char arrays rau luv luv textsand tiv thaiv koj los ntawm tsis overruns. Ntxiv rau lawv nyeem tau ntau dua thiab siv tau yooj yim dua.

Qhov txawv ntawm char * thiab char yog dab tsi?

1 Teb. Cov txawv char * tus pointer thiab char array yog li cas koj cuam tshuam nrog lawv tom qab koj tsim lawv. Qhov tseem ceeb txawv yog nyob rau hauv ib char * koj muab nws rau tus pointer, uas yog avariable. Hauv char koj tab tom muab nws rau ib qho array uas tsis yog qhov sib txawv.