Obyektlarga xarita

Sizda 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 boâ€™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 koâ€™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, oâ€™q funktsiyalari uchun biz qoâ€™shimcha qavslardan foydalanishimiz kerakligini unutmang.

Biz bunday yozolmaymiz:

          let usersMapped = users.map(user => {
  fullName: `${user.name} ${user.surname}`,
  id: user.id
});
        

Yodimizda boâ€™lganidek, ikkita oâ€™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 â€œoddiyâ€ qavslarga oâ€™rashdan iborat:

          let usersMapped = users.map(user => ({
  fullName: `${user.name} ${user.surname}`,
  id: user.id
}));
        

Endi yaxshi.