GeezerVison is showing uz.javascript.info — Obyektlarga xarita darsga qaytishSizda user obyekyektlar massivi mavjud, ularning har birida ism, familiya va id mavjud.
Undan id va fullName obyektlarining boshqa massivni yaratish uchun kodni yozing, bu yerda to'liq ism ism va familiya dan hosil bo’ladi.
Masalan:
let john = { name: "John", surname: "Smith", id: 1 };
let pete = { name: "Pete", surname: "Hunt", id: 2 };
let mary = { name: "Mary", surname: "Key", id: 3 };
let users = [ john, pete, mary ];
let usersMapped = /* ... sizning kodingiz ... */
/*
usersMapped = [
{ fullName: "John Smith", id: 1 },
{ fullName: "Pete Hunt", id: 2 },
{ fullName: "Mary Key", id: 3 }
]
*/
alert( usersMapped[0].id ) // 1
alert( usersMapped[0].fullName ) // John Smith
Shunday qilib, aslida siz bir obyektlar massivini boshqasiga solishtirishingiz kerak. Bu erda => dan foydalanib ko’ring.
let john = { name: "John", surname: "Smith", id: 1 };
let pete = { name: "Pete", surname: "Hunt", id: 2 };
let mary = { name: "Mary", surname: "Key", id: 3 };
let users = [ john, pete, mary ];
let usersMapped = users.map(user => ({
fullName: `${user.name} ${user.surname}`,
id: user.id
}));
/*
usersMapped = [
{ fullName: "John Smith", id: 1 },
{ fullName: "Pete Hunt", id: 2 },
{ fullName: "Mary Key", id: 3 }
]
*/
alert( usersMapped[0].id ); // 1
alert( usersMapped[0].fullName ); // John Smith
Iltimos, o’q funktsiyalari uchun biz qo’shimcha qavslardan foydalanishimiz kerakligini unutmang.
Biz bunday yozolmaymiz:
let usersMapped = users.map(user => {
fullName: `${user.name} ${user.surname}`,
id: user.id
});
Yodimizda bo’lganidek, ikkita o’q funktsiyasi mavjud: tanasiz value => expr va tanali value => {...}.
Bu erda JavaScript { ni obyektning boshlanishi emas, balki funktsiya tanasining boshlanishi sifatida qabul qiladi. Vaqtinchalik yechim ularni “oddiy” qavslarga o’rashdan iborat:
let usersMapped = users.map(user => ({
fullName: `${user.name} ${user.surname}`,
id: user.id
}));
Endi yaxshi.
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