Menene bambanci tsakanin watch da watchEffect?

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Dukansu suna gudana alamomin gefe a halin gajeriyar canje-canjen, amma suna bambanta a yadda a zata ƙofa abubuwa da bayani da suke bayarwa muku. Yi amfani da su don alamomin gefe (kiran API, rubuta, aikin DOM na hannu) — **ba** don samun dabi'u (hakan shine `computed`). ## watch — tushen bayyane, yana ba da tsofua da sabunta dabi'u ```vue ``` `watch` yana kula da tushe **takaici** da kuka nuna, ya gudana bugun call ne kawai lokacin da tushen nan ya canja, kuma yana ba da **tsofua da sabunta dabi'u** — mai fa'ida lokacin da kuke bukatar kwatanta su ko amsa wani takaici sashi na jiha. ## watchEffect — sanaye-sanaye na abubuwa na jingina, ya gudana nan da nan ```vue ``` `watchEffect` **yana samuwa jiya** kowane dabi'u mai amfani da aka yi amfani a cikinsa (babu jerin tushe), kuma ya **gudana nan da nan akan shimfidar** (sannan ya sake gudana kan kowane canjin abubuwa). Babu tsofua/sabunta dabi'u. ## A gefen jiya ```text watch watchEffect Dependencies explicit (you name them) automatic (tracked from usage) Runs immediately? no (unless immediate:true) yes Old + new values? yes no Best for reacting to specific state, running an effect that depends needing prev value on several values ``` ## Zaɓin watch masu amfani ```js watch(source, cb, { immediate: true, // run once right away (like watchEffect) deep: true, // watch nested object changes }); watch([a, b], ([newA, newB]) => {}); // watch multiple sources ``` ## Me ya sa haka muhimmi Zaɓin kayan aikin daidai yana kiyaye alamomin gefe na abubuwa masu rai na tsarki: yi amfani da **`computed`** don dabi'u masu dangana, **`watch`** lokacin da kuke bukatar amsa tushe takaici ko kwatanta tsofua/sabunta (m.z. bugi lokacin da id ya canja), da **`watchEffect`** don alamomi masu dangana da wani dabi'u da koda suke maye ƙofa su ta jingina. Yi amfani mara kyau da masu kula don samun dabi'u (maimakon `computed`) shine wata sararin yalabar nan.