Cov txheej txheem:
Video: Yuav ua li cas koj tsim ib tug database siv code thawj txoj hauv kev hauv Entity Framework?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Tsim Cov Ntaub Ntawv Tshiab Siv Cov Cai Ua Ntej Hauv Chaw Ua Haujlwm
- Kauj ruam 1 - Tsim Windows form project.
- Kauj ruam 2 - Ntxiv qhov chaw ncej ua hauj lwm rau hauv qhov project tshiab tsim siv NuGet pob.
- Kauj ruam 3 - Tsim Model nyob rau hauv qhov project.
- Kauj ruam 4 - Tsim Cov ntsiab lus hauv chav kawm hauv qhov project.
- Kauj ruam 5 - Tshaj tawm ntaus DbSet rau txhua chav kawm ntawm tus qauv.
- Kauj ruam 6 - Tsim input seem.
Xav txog qhov no, dab tsi yog code thawj txoj hauv kev hauv Entity Framework?
Code thawj mus kom ze cia peb hloov peb cov chav kawm coded rau hauv daim ntawv thov database, uas txhais tau tias code ua ntej cia peb txheeb xyuas peb tus qauv sau npe siv POCO (cov khoom qub qub CLR) chav kawm tsis yog siv cov ntaub ntawv XML-based EDMX uas tsis muaj kev vam khom nrog Lub Koom Haum Ua Haujlwm.
Ib sab saum toj, dab tsi yog code ua ntej los ntawm database? Nquag Code ua ntej hais txog kev tsim cov database los ntawm koj POCO tab sis feem ntau yog thaum koj tab tom tsom rau qhov uas twb muaj lawm database koj tuaj yeem muaj VS cov cuab yeej tsim cov chav kawm rau koj kom sawv thiab khiav nrawm.
Yog li ntawd, kuv yuav ua li cas thiaj tsim tau tus qauv database hauv Entity Framework?
Tsim qauv
- Xaiv Tus Qauv Tshiab los ntawm cov ntawv qhia zaub mov.
- Xaiv Tus Qauv Qauv, qhia nws Lub Npe thiab nyem Tsim.
- Nyem Next.
- Xaiv ib tus neeg muab kev pabcuam hauv cov chaw muab kev pabcuam thiab teeb tsa cov kev sib txuas uas xav tau, tom qab ntawd nyem Next.
- Xaiv Tsim Los Ntawm Database thiab nyem Next.
Dab tsi yog DbContext hauv Entity Framework?
Cov DbContext chav kawm yog ib feem tseem ceeb ntawm Lub Koom Haum Ua Haujlwm . Ib qho piv txwv ntawm DbContext sawv cev rau kev sib tham nrog cov ntaub ntawv uas tuaj yeem siv los nug thiab khaws cov xwm txheej ntawm koj cov koom haum mus rau database. DbContext yog ib qho kev sib xyaw ua ke ntawm Chav Ua Haujlwm ntawm Kev Ua Haujlwm thiab Cov Txheej Txheem Kev Tso Cai.
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