Postfix ! yana gaya wa mai haɗa "Na tabbata wannan darajar ba null ba ko undefined ba" — yana cire null/undefined daga nau'insa ba tare da wata ƙuntatacciyar lokaci ba.
() {
.(name!.());
}
Postfix ! yana gaya wa mai haɗa "Na tabbata wannan darajar ba null ba ko undefined ba" — yana cire null/undefined daga nau'insa ba tare da wata ƙuntatacciyar lokaci ba.
() {
.(name!.());
}
Abi ne na lokacin hada kawai — kamar as, ba ya yi kome bada-jiyya na lokaci ba. Idan ka kuruji, ya faɗi:
const el = document.getElementById("app")!; // assert non-null
el.innerHTML = "hi"; // 💥 runtime error if #app doesn't actually exist
// 1. You've logically guaranteed it, but the compiler can't see it
if (map.has(key)) map.get(key)!.doThing(); // has() proves get() isn't undefined
// 2. Class fields initialized outside the constructor (DI, lifecycle hooks)
class C { value!: string; } // definite assignment assertion
name?.toUpperCase(); // optional chaining — no crash, yields undefined
const x = name ?? "default"; // provide a fallback
if (name) name.toUpperCase(); // narrow with a real check
Duk ɗaya daga cikinsu yana shakatawa yanayin da ba a gane ba maimakon kirkirra shi.
! aiki ne mai karﻓi: yana shiyar da marmarin karewa mai aminci mai haɗa cewa yake gwaje-gwaje.
Ya zama sha'awa (kana da ilimi mai samu-samu ba ya ɗa sanin haka), amma idan ka kai wa girma sosai sai ka sake buɗe daidai rashin aminci-kasa buttude-bugaje wanda strictNullChecks ya dakatar.
Bari a je ?., ??, ko bayyananniyar gadi a nan gida; buga ! kawai lokacin da za ka iya tabbataa ba-ɗakatar-marmarin da gaske.