Tus tsim nyog const tuaj yeem siv rau qhov tshaj tawm ntawm txhua qhov sib txawvtxhawm rau qhia tias nws tus nqi yuav tsis hloov pauv (uas yog nyob ntawm qhov chaw sib txawv ntawm qhov chaw khaws cia, peb tuaj yeem hloov pauv. tus nqi ntawm const variable los ntawm kev siv pointer).
Dab tsi yog siv const qualifier hauv C lus?
Peb siv const qualifier tshaj tawm qhov sib txawv raws li qhov tas mus li Qhov ntawd txhais tau tias peb tsis tuaj yeem hloov tus nqi thaum qhov sib txawv tau pib. … Piv txwv li, yog tias koj muaj tus nqi tas li ntawm tus nqi ntawm PI, koj yuav tsis nyiam ib feem ntawm qhov kev pab cuam los hloov tus nqi ntawd.
siv cov kev tsim nyog tas li nyob qhov twg?
Thaum peb tsis xav hloov qhov kev sib cav thiab dhau nws raws li kev siv lossis pointer, peb siv const qualifier kom qhov kev sib cav tsis raug hloov pauv hauv kev ua haujlwm. Cov tub ntxhais kawm cov ntaub ntawv tuaj yeem raug tshaj tawm tias yog ob qho tib si const thiab zoo li qub rau cov chav kawm dav. Reference variables yuav const thaum lawv xa mus rau qhov chaw const.
Tus tswvcuab ua haujlwm tsim nyog ua dab tsi?
Tus neeg tsim nyog const thaum kawg ntawm kev tshaj tawm cov tswv cuab ua haujlwm qhia tau hais tias txoj haujlwm tuaj yeem hu rau ntawm cov khoom uas lawv tus kheej const. const cov tswv cuab ua haujlwm cog lus tias yuav tsis hloov lub xeev ntawm cov tswvcuab cov ntaub ntawv tsis hloov pauv.
Dab tsi yog qhov tsim nyog hauv C ++?
Peb siv const qualifier tshaj tawm qhov sib txawv raws li qhov tas mus li Qhov ntawd txhais tau tias peb tsis tuaj yeem hloov tus nqi thaum qhov sib txawv tau pib. … Piv txwv li, yog tias koj muaj tus nqi tas li ntawm tus nqi ntawm PI, koj yuav tsis nyiam ib feem ntawm qhov kev pab cuam los hloov tus nqi ntawd. Yog li koj yuav tsum tshaj tawm tias yog ib qho const.