Lokacin da kake jera jeri, React na bukatan hanya don sanin wanne item ne wanne tsakanin renders don ya iya sake amfani, saitawa, saka, ko gidaje DOM nodes daidai. key shine wannan ainihi.
{users.map(user => (
<Row key={user.id} user={user} /> // stable, unique id
))}
Yin amfani da index a matsayin maɓalli yana gaya wa React "item a tasi 0 shine item na gida" — wanda ya karce a nan gida lokacin jeri ya saitawa, ko kuma ka saka/cire daga gida:
// items: [A, B, C] with keys 0,1,2
// you DELETE A → [B, C], keys become 0,1
// React thinks key 0 (was A) is now B, key 1 (was B) is now C...
// so it keeps the wrong DOM state with the wrong item.
Ainihin alamar: jeri na inputan inda rubuta a jeri daya "zage" zuwa jeri daban bayan cire/daidaita, saboda React ya sake amfani da daidai <input> (da kuma cikinta/abin jiya na ciki).
user.id, slug).Key shine illela ga algorithm na maimaita; samun daidaita daya a tabbatar da gida duka aiki da yanayin haɗi.