Video: Puas yog null siv tau hauv JSON?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
RFC 7159 tau luam tawm thaum Lub Peb Hlis 2014 thiab hloov kho RFC 4627. Qhov no txhais tau tias nrog RFC 7159, " null ” (raws li "tseeb" thiab "false") ua ib siv tau JSON ntawv nyeem. Yog li cov JSON text serialized tus nqi ntawm a null qhov khoom yog qhov tseeb " null ”. Hmoov tsis, tsis yog txhua tus JSON parsers / deserializers txhawb parsing txoj hlua " null ”.
Xav txog qhov no, puas yog NULL tso cai hauv JSON?
Cov hlua, Booleans thiab cov lej tsis muaj daim ntawv 'tsis muaj', yog li nws siv tau null tus nqi. JSON muaj tus nqi tshwj xeeb hu ua null uas tuaj yeem teeb tsa rau txhua hom ntaub ntawv suav nrog arrays, khoom, naj npawb thiab boolean hom.
Kuj Paub, yog ib txoj hlua khoob siv tau JSON? Thaum ib txoj hlua khoob tsis yog siv tau JSON ob quotes yog siv tau JSON . Qhov no yog ib qho tseem ceeb sib txawv. Qhov no yog hais tias a txoj hlua uas muaj ob nqe lus tsis yog tib yam li ib qho txoj hlua khoob . JSON.
Ib sab ntawm no, puas yog JSON tsis raug cai?
tsis tau txhais tsis yog a siv json tus nqi, txawm tias nws yog siv tau hauv javascript. Los ntawm official json Txheem (ECMA-404, Tshooj 5): A JSON tus nqi tuaj yeem yog ib qho khoom, array, tus lej, txoj hlua, qhov tseeb, tsis tseeb, lossis null.
Koj tsis quav ntsej NULL qhov tseem ceeb hauv JSON li cas?
Yuav kom tswj tau zoo dua JSON tso zis, koj ua tau ignore null fields , thiab Jackson muab ob peb txoj hauv kev los ua qhov ntawd. Koj ua tau ignore null fields ntawm chav kawm los ntawm kev siv @JsonInclude(Include. NON_NULL) tsuas yog suav nrog cov tsis- teb null , yog li tsis suav nrog txhua tus cwj pwm uas nws tus nqi yog null.
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