Cara menggunakan set di javascript

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Panduan Referensi API AWS SDK for JavaScript V3 menjelaskan secara detail semua operasi API untuk AWS SDK for JavaScript versi 3 (V3)

Table of Contents Show

Tentang contoh
Tugas prasyarat
Bergabunglah dengan antrean Anda

Terjemahan disediakan oleh mesin penerjemah. Jika konten yang diterjemahkan bertentangan dengan versi bahasa Inggris asli, versi bahasa Inggris yang akan berlaku

Contoh kode node. Ini menunjukkan

Cara mendapatkan daftar semua antrean pesan Anda
Cara mendapatkan URL untuk antrean tertentu
Cara membuat dan menghapus antrian

Tentang contoh

Dalam contoh ini, serangkaian Node. js digunakan untuk bekerja dengan antrian. Modul simpul. js menggunakan SDK untuk JavaScript guna mengaktifkan antrean untuk memanggil metode berikut

// Import required AWS SDK clients and commands for Node.js
import { ListQueuesCommand } from  "@aws-sdk/client-sqs";
import { sqsClient } from  "./libs/sqsClient.js";

const run = async () => {
  try {
    const data = await sqsClient.send(new ListQueuesCommand({}));
    console.log("Success", data);
    return data; // For unit tests.
  } catch (err) {
    console.error(err, err.stack);
  }
};
run();

4Kelas klien

Untuk informasi selengkapnya tentang pesan Amazon SQS, lihat Cara Kerja Antrean di Amazon Simple Que Service

Tugas prasyarat

Untuk menyiapkan dan menjalankan contoh ini, Anda harus menyelesaikan tugas berikut

Siapkan lingkungan proyek untuk menjalankan contoh Node TypeScript ini, dan pasang AWS SDK yang diperlukan untuk JavaScript dan modul pihak ketiga. Ikuti petunjuk di GitHub
Buat file konfigurasi bersama dengan kredensial pengguna Anda. Untuk informasi lebih lanjut tentang menyiapkan file kredensial bersama, lihat Memuat kredensial di Node. js dari file kredensial bersama

Contoh-contoh ini menunjukkan cara mengimpor/mengekspor objek dan perintah layanan klien menggunakan ECMAScript6 (ES6)

Bergabunglah dengan antrean Anda

Buat

// Import required AWS SDK clients and commands for Node.js
import { ListQueuesCommand } from  "@aws-sdk/client-sqs";
import { sqsClient } from  "./libs/sqsClient.js";

const run = async () => {
  try {
    const data = await sqsClient.send(new ListQueuesCommand({}));
    console.log("Success", data);
    return data; // For unit tests.
  } catch (err) {
    console.error(err, err.stack);
  }
};
run();

_5direktori, dan buat modul Node. js dengan nama file

// Import required AWS SDK clients and commands for Node.js
import { ListQueuesCommand } from  "@aws-sdk/client-sqs";
import { sqsClient } from  "./libs/sqsClient.js";

const run = async () => {
  try {
    const data = await sqsClient.send(new ListQueuesCommand({}));
    console.log("Success", data);
    return data; // For unit tests.
  } catch (err) {
    console.error(err, err.stack);
  }
};
run();

6. Salin dan tempel kode di bawah ini ke dalamnya, yang membuat objek klien Amazon SQS. Ganti

// Import required AWS SDK clients and commands for Node.js
import { ListQueuesCommand } from  "@aws-sdk/client-sqs";
import { sqsClient } from  "./libs/sqsClient.js";

const run = async () => {
  try {
    const data = await sqsClient.send(new ListQueuesCommand({}));
    console.log("Success", data);
    return data; // For unit tests.
  } catch (err) {
    console.error(err, err.stack);
  }
};
run();

_7 dengan AWSRegion

import  { SQSClient } from "@aws-sdk/client-sqs";
// Set the AWS Region.
const REGION = "REGION"; //e.g. "us-east-1"
// Create SQS service object.
const sqsClient = new SQSClient({ region: REGION });
export  { sqsClient };

_

Kode contoh ini dapat ditemukan di sini di GitHub

Buat modul Node. js dengan nama file

import  { SQSClient } from "@aws-sdk/client-sqs";
// Set the AWS Region.
const REGION = "REGION"; //e.g. "us-east-1"
// Create SQS service object.
const sqsClient = new SQSClient({ region: REGION });
export  { sqsClient };

_0. Pastikan untuk mengonfigurasi SDK seperti yang ditunjukkan sebelumnya, termasuk mengunduh klien dan paket yang diperlukan. Buat objek JSON yang berisi parameter yang diperlukan untuk menghapus antrean, terdiri dari URL antrean yang ingin Anda hapus. Metode panggilan

import  { SQSClient } from "@aws-sdk/client-sqs";
// Set the AWS Region.
const REGION = "REGION"; //e.g. "us-east-1"
// Create SQS service object.
const sqsClient = new SQSClient({ region: REGION });
export  { sqsClient };

_1

Objek Set_ memungkinkan Anda menyimpan nilai unik dari jenis apa pun, baik nilai primitif atau referensi objek

Set_ objek adalah kumpulan nilai. Nilai dalam Set hanya dapat muncul sekali; . Anda dapat mengulangi elemen-elemen dari suatu set dalam urutan penyisipan. Urutan penyisipan sesuai dengan urutan di mana setiap elemen berhasil dimasukkan ke dalam set dengan metode

for (const item of mySet1) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

for (const item of mySet1.keys()) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

for (const item of mySet1.values()) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

// key and value are the same here
for (const [key, value] of mySet1.entries()) {
  console.log(key);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

// Convert Set object to an Array object, with Array.from
const myArr = Array.from(mySet1) // [1, "some text", {"a": 1, "b": 2}, {"a": 1, "b": 2}, 5]

// the following will also work if run in an HTML document
mySet1.add(document.body)
mySet1.has(document.querySelector('body')) // true

// converting between Set and Array
const mySet2 = new Set([1, 2, 3, 4]);
console.log(mySet2.size); // 4
console.log([...mySet2]); // [1, 2, 3, 4]

// intersect can be simulated via
const intersection = new Set([...mySet1].filter((x) => mySet2.has(x)));

// difference can be simulated via
const difference = new Set([...mySet1].filter((x) => !mySet2.has(x)));

// Iterate set entries with forEach()
mySet2.forEach((value) => {
  console.log(value);
});
// 1
// 2
// 3
// 4

1 (yaitu, belum ada elemen identik yang sudah ada di set ketika

for (const item of mySet1) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

for (const item of mySet1.keys()) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

for (const item of mySet1.values()) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

// key and value are the same here
for (const [key, value] of mySet1.entries()) {
  console.log(key);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

// Convert Set object to an Array object, with Array.from
const myArr = Array.from(mySet1) // [1, "some text", {"a": 1, "b": 2}, {"a": 1, "b": 2}, 5]

// the following will also work if run in an HTML document
mySet1.add(document.body)
mySet1.has(document.querySelector('body')) // true

// converting between Set and Array
const mySet2 = new Set([1, 2, 3, 4]);
console.log(mySet2.size); // 4
console.log([...mySet2]); // [1, 2, 3, 4]

// intersect can be simulated via
const intersection = new Set([...mySet1].filter((x) => mySet2.has(x)));

// difference can be simulated via
const difference = new Set([...mySet1].filter((x) => !mySet2.has(x)));

// Iterate set entries with forEach()
mySet2.forEach((value) => {
  console.log(value);
});
// 1
// 2
// 3
// 4

1 dipanggil)

Spesifikasi membutuhkan set untuk diimplementasikan "yang, rata-rata, memberikan waktu akses yang sublinear pada jumlah elemen dalam koleksi". Oleh karena itu, ini dapat direpresentasikan secara internal sebagai tabel hash (dengan pencarian O(1)), pohon pencarian (dengan pencarian O(log(N))), atau struktur data lainnya, selama kompleksitasnya lebih baik daripada O (N)

Kesetaraan nilai didasarkan pada algoritma. (Dulu menggunakan , yang memperlakukan

for (const item of mySet1) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

for (const item of mySet1.keys()) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

for (const item of mySet1.values()) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

// key and value are the same here
for (const [key, value] of mySet1.entries()) {
  console.log(key);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

// Convert Set object to an Array object, with Array.from
const myArr = Array.from(mySet1) // [1, "some text", {"a": 1, "b": 2}, {"a": 1, "b": 2}, 5]

// the following will also work if run in an HTML document
mySet1.add(document.body)
mySet1.has(document.querySelector('body')) // true

// converting between Set and Array
const mySet2 = new Set([1, 2, 3, 4]);
console.log(mySet2.size); // 4
console.log([...mySet2]); // [1, 2, 3, 4]

// intersect can be simulated via
const intersection = new Set([...mySet1].filter((x) => mySet2.has(x)));

// difference can be simulated via
const difference = new Set([...mySet1].filter((x) => !mySet2.has(x)));

// Iterate set entries with forEach()
mySet2.forEach((value) => {
  console.log(value);
});
// 1
// 2
// 3
// 4

3 dan

for (const item of mySet1) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

for (const item of mySet1.keys()) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

for (const item of mySet1.values()) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

// key and value are the same here
for (const [key, value] of mySet1.entries()) {
  console.log(key);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

// Convert Set object to an Array object, with Array.from
const myArr = Array.from(mySet1) // [1, "some text", {"a": 1, "b": 2}, {"a": 1, "b": 2}, 5]

// the following will also work if run in an HTML document
mySet1.add(document.body)
mySet1.has(document.querySelector('body')) // true

// converting between Set and Array
const mySet2 = new Set([1, 2, 3, 4]);
console.log(mySet2.size); // 4
console.log([...mySet2]); // [1, 2, 3, 4]

// intersect can be simulated via
const intersection = new Set([...mySet1].filter((x) => mySet2.has(x)));

// difference can be simulated via
const difference = new Set([...mySet1].filter((x) => !mySet2.has(x)));

// Iterate set entries with forEach()
mySet2.forEach((value) => {
  console.log(value);
});
// 1
// 2
// 3
// 4

4 berbeda. Memeriksa. ) Ini berarti

for (const item of mySet1) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

for (const item of mySet1.keys()) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

for (const item of mySet1.values()) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

// key and value are the same here
for (const [key, value] of mySet1.entries()) {
  console.log(key);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

// Convert Set object to an Array object, with Array.from
const myArr = Array.from(mySet1) // [1, "some text", {"a": 1, "b": 2}, {"a": 1, "b": 2}, 5]

// the following will also work if run in an HTML document
mySet1.add(document.body)
mySet1.has(document.querySelector('body')) // true

// converting between Set and Array
const mySet2 = new Set([1, 2, 3, 4]);
console.log(mySet2.size); // 4
console.log([...mySet2]); // [1, 2, 3, 4]

// intersect can be simulated via
const intersection = new Set([...mySet1].filter((x) => mySet2.has(x)));

// difference can be simulated via
const difference = new Set([...mySet1].filter((x) => !mySet2.has(x)));

// Iterate set entries with forEach()
mySet2.forEach((value) => {
  console.log(value);
});
// 1
// 2
// 3
// 4

5 dianggap sama dengan

for (const item of mySet1) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

for (const item of mySet1.keys()) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

for (const item of mySet1.values()) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

// key and value are the same here
for (const [key, value] of mySet1.entries()) {
  console.log(key);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

// Convert Set object to an Array object, with Array.from
const myArr = Array.from(mySet1) // [1, "some text", {"a": 1, "b": 2}, {"a": 1, "b": 2}, 5]

// the following will also work if run in an HTML document
mySet1.add(document.body)
mySet1.has(document.querySelector('body')) // true

// converting between Set and Array
const mySet2 = new Set([1, 2, 3, 4]);
console.log(mySet2.size); // 4
console.log([...mySet2]); // [1, 2, 3, 4]

// intersect can be simulated via
const intersection = new Set([...mySet1].filter((x) => mySet2.has(x)));

// difference can be simulated via
const difference = new Set([...mySet1].filter((x) => !mySet2.has(x)));

// Iterate set entries with forEach()
mySet2.forEach((value) => {
  console.log(value);
});
// 1
// 2
// 3
// 4

5 (meskipun

for (const item of mySet1) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

for (const item of mySet1.keys()) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

for (const item of mySet1.values()) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

// key and value are the same here
for (const [key, value] of mySet1.entries()) {
  console.log(key);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

// Convert Set object to an Array object, with Array.from
const myArr = Array.from(mySet1) // [1, "some text", {"a": 1, "b": 2}, {"a": 1, "b": 2}, 5]

// the following will also work if run in an HTML document
mySet1.add(document.body)
mySet1.has(document.querySelector('body')) // true

// converting between Set and Array
const mySet2 = new Set([1, 2, 3, 4]);
console.log(mySet2.size); // 4
console.log([...mySet2]); // [1, 2, 3, 4]

// intersect can be simulated via
const intersection = new Set([...mySet1].filter((x) => mySet2.has(x)));

// difference can be simulated via
const difference = new Set([...mySet1].filter((x) => !mySet2.has(x)));

// Iterate set entries with forEach()
mySet2.forEach((value) => {
  console.log(value);
});
// 1
// 2
// 3
// 4

7) dan semua nilai lainnya dianggap sama menurut semantik operator

for (const item of mySet1) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

for (const item of mySet1.keys()) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

for (const item of mySet1.values()) {
  console.log(item);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

// key and value are the same here
for (const [key, value] of mySet1.entries()) {
  console.log(key);
}
// 1, "some text", { "a": 1, "b": 2 }, { "a": 1, "b": 2 }, 5

// Convert Set object to an Array object, with Array.from
const myArr = Array.from(mySet1) // [1, "some text", {"a": 1, "b": 2}, {"a": 1, "b": 2}, 5]

// the following will also work if run in an HTML document
mySet1.add(document.body)
mySet1.has(document.querySelector('body')) // true

// converting between Set and Array
const mySet2 = new Set([1, 2, 3, 4]);
console.log(mySet2.size); // 4
console.log([...mySet2]); // [1, 2, 3, 4]

// intersect can be simulated via
const intersection = new Set([...mySet1].filter((x) => mySet2.has(x)));

// difference can be simulated via
const difference = new Set([...mySet1].filter((x) => !mySet2.has(x)));

// Iterate set entries with forEach()
mySet2.forEach((value) => {
  console.log(value);
});
// 1
// 2
// 3
// 4

8

Metode Set

function isSuperset(set, subset) {
  for (const elem of subset) {
    if (!set.has(elem)) {
      return false;
    }
  }
  return true;
}

function union(setA, setB) {
  const _union = new Set(setA);
  for (const elem of setB) {
    _union.add(elem);
  }
  return _union;
}

function intersection(setA, setB) {
  const _intersection = new Set();
  for (const elem of setB) {
    if (setA.has(elem)) {
      _intersection.add(elem);
    }
  }
  return _intersection;
}

function symmetricDifference(setA, setB) {
  const _difference = new Set(setA);
  for (const elem of setB) {
    if (_difference.has(elem)) {
      _difference.delete(elem);
    } else {
      _difference.add(elem);
    }
  }
  return _difference;
}

function difference(setA, setB) {
  const _difference = new Set(setA);
  for (const elem of setB) {
    _difference.delete(elem);
  }
  return _difference;
}

// Examples
const setA = new Set([1, 2, 3, 4])
const setB = new Set([2, 3])
const setC = new Set([3, 4, 5, 6])

isSuperset(setA, setB)          // returns true
union(setA, setC)               // returns Set {1, 2, 3, 4, 5, 6}
intersection(setA, setC)        // returns Set {3, 4}
symmetricDifference(setA, setC) // returns Set {1, 2, 5, 6}
difference(setA, setC)          // returns Set {1, 2}

0 memeriksa apakah suatu nilai ada dalam objek Set, menggunakan pendekatan yang, rata-rata, lebih cepat daripada menguji sebagian besar elemen yang sebelumnya telah ditambahkan ke objek Set. Secara khusus, ini, rata-rata, lebih cepat daripada metode

function isSuperset(set, subset) {
  for (const elem of subset) {
    if (!set.has(elem)) {
      return false;
    }
  }
  return true;
}

function union(setA, setB) {
  const _union = new Set(setA);
  for (const elem of setB) {
    _union.add(elem);
  }
  return _union;
}

function intersection(setA, setB) {
  const _intersection = new Set();
  for (const elem of setB) {
    if (setA.has(elem)) {
      _intersection.add(elem);
    }
  }
  return _intersection;
}

function symmetricDifference(setA, setB) {
  const _difference = new Set(setA);
  for (const elem of setB) {
    if (_difference.has(elem)) {
      _difference.delete(elem);
    } else {
      _difference.add(elem);
    }
  }
  return _difference;
}

function difference(setA, setB) {
  const _difference = new Set(setA);
  for (const elem of setB) {
    _difference.delete(elem);
  }
  return _difference;
}

// Examples
const setA = new Set([1, 2, 3, 4])
const setB = new Set([2, 3])
const setC = new Set([3, 4, 5, 6])

isSuperset(setA, setB)          // returns true
union(setA, setC)               // returns Set {1, 2, 3, 4, 5, 6}
intersection(setA, setC)        // returns Set {3, 4}
symmetricDifference(setA, setC) // returns Set {1, 2, 5, 6}
difference(setA, setC)          // returns Set {1, 2}

3 ketika objek

function isSuperset(set, subset) {
  for (const elem of subset) {
    if (!set.has(elem)) {
      return false;
    }
  }
  return true;
}

function union(setA, setB) {
  const _union = new Set(setA);
  for (const elem of setB) {
    _union.add(elem);
  }
  return _union;
}

function intersection(setA, setB) {
  const _intersection = new Set();
  for (const elem of setB) {
    if (setA.has(elem)) {
      _intersection.add(elem);
    }
  }
  return _intersection;
}

function symmetricDifference(setA, setB) {
  const _difference = new Set(setA);
  for (const elem of setB) {
    if (_difference.has(elem)) {
      _difference.delete(elem);
    } else {
      _difference.add(elem);
    }
  }
  return _difference;
}

function difference(setA, setB) {
  const _difference = new Set(setA);
  for (const elem of setB) {
    _difference.delete(elem);
  }
  return _difference;
}

// Examples
const setA = new Set([1, 2, 3, 4])
const setB = new Set([2, 3])
const setC = new Set([3, 4, 5, 6])

isSuperset(setA, setB)          // returns true
union(setA, setC)               // returns Set {1, 2, 3, 4, 5, 6}
intersection(setA, setC)        // returns Set {3, 4}
symmetricDifference(setA, setC) // returns Set {1, 2, 5, 6}
difference(setA, setC)          // returns Set {1, 2}

4 memiliki

function isSuperset(set, subset) {
  for (const elem of subset) {
    if (!set.has(elem)) {
      return false;
    }
  }
  return true;
}

function union(setA, setB) {
  const _union = new Set(setA);
  for (const elem of setB) {
    _union.add(elem);
  }
  return _union;
}

function intersection(setA, setB) {
  const _intersection = new Set();
  for (const elem of setB) {
    if (setA.has(elem)) {
      _intersection.add(elem);
    }
  }
  return _intersection;
}

function symmetricDifference(setA, setB) {
  const _difference = new Set(setA);
  for (const elem of setB) {
    if (_difference.has(elem)) {
      _difference.delete(elem);
    } else {
      _difference.add(elem);
    }
  }
  return _difference;
}

function difference(setA, setB) {
  const _difference = new Set(setA);
  for (const elem of setB) {
    _difference.delete(elem);
  }
  return _difference;
}

// Examples
const setA = new Set([1, 2, 3, 4])
const setB = new Set([2, 3])
const setC = new Set([3, 4, 5, 6])

isSuperset(setA, setB)          // returns true
union(setA, setC)               // returns Set {1, 2, 3, 4, 5, 6}
intersection(setA, setC)        // returns Set {3, 4}
symmetricDifference(setA, setC) // returns Set {1, 2, 5, 6}
difference(setA, setC)          // returns Set {1, 2}

5 sama dengan ________ 46 _______ objek

function isSuperset(set, subset) {
  for (const elem of subset) {
    if (!set.has(elem)) {
      return false;
    }
  }
  return true;
}

function union(setA, setB) {
  const _union = new Set(setA);
  for (const elem of setB) {
    _union.add(elem);
  }
  return _union;
}

function intersection(setA, setB) {
  const _intersection = new Set();
  for (const elem of setB) {
    if (setA.has(elem)) {
      _intersection.add(elem);
    }
  }
  return _intersection;
}

function symmetricDifference(setA, setB) {
  const _difference = new Set(setA);
  for (const elem of setB) {
    if (_difference.has(elem)) {
      _difference.delete(elem);
    } else {
      _difference.add(elem);
    }
  }
  return _difference;
}

function difference(setA, setB) {
  const _difference = new Set(setA);
  for (const elem of setB) {
    _difference.delete(elem);
  }
  return _difference;
}

// Examples
const setA = new Set([1, 2, 3, 4])
const setB = new Set([2, 3])
const setC = new Set([3, 4, 5, 6])

isSuperset(setA, setB)          // returns true
union(setA, setC)               // returns Set {1, 2, 3, 4, 5, 6}
intersection(setA, setC)        // returns Set {3, 4}
symmetricDifference(setA, setC) // returns Set {1, 2, 5, 6}
difference(setA, setC)          // returns Set {1, 2}

7

function isSuperset(set, subset) {
  for (const elem of subset) {
    if (!set.has(elem)) {
      return false;
    }
  }
  return true;
}

function union(setA, setB) {
  const _union = new Set(setA);
  for (const elem of setB) {
    _union.add(elem);
  }
  return _union;
}

function intersection(setA, setB) {
  const _intersection = new Set();
  for (const elem of setB) {
    if (setA.has(elem)) {
      _intersection.add(elem);
    }
  }
  return _intersection;
}

function symmetricDifference(setA, setB) {
  const _difference = new Set(setA);
  for (const elem of setB) {
    if (_difference.has(elem)) {
      _difference.delete(elem);
    } else {
      _difference.add(elem);
    }
  }
  return _difference;
}

function difference(setA, setB) {
  const _difference = new Set(setA);
  for (const elem of setB) {
    _difference.delete(elem);
  }
  return _difference;
}

// Examples
const setA = new Set([1, 2, 3, 4])
const setB = new Set([2, 3])
const setC = new Set([3, 4, 5, 6])

isSuperset(setA, setB)          // returns true
union(setA, setC)               // returns Set {1, 2, 3, 4, 5, 6}
intersection(setA, setC)        // returns Set {3, 4}
symmetricDifference(setA, setC) // returns Set {1, 2, 5, 6}
difference(setA, setC)          // returns Set {1, 2}

8

Membuat objek ________46______ baru

const myArray = ['value1', 'value2', 'value3'];

// Use the regular Set constructor to transform an Array into a Set
const mySet = new Set(myArray);

mySet.has('value1')     // returns true

// Use the spread syntax to transform a set into an Array.
console.log([...mySet]); // Will show you exactly the same Array as myArray

0

Fungsi konstruktor yang digunakan untuk membuat objek turunan

const myArray = ['value1', 'value2', 'value3'];

// Use the regular Set constructor to transform an Array into a Set
const mySet = new Set(myArray);

mySet.has('value1')     // returns true

// Use the spread syntax to transform a set into an Array.
console.log([...mySet]); // Will show you exactly the same Array as myArray

1

Nilai awal dari properti

const myArray = ['value1', 'value2', 'value3'];

// Use the regular Set constructor to transform an Array into a Set
const mySet = new Set(myArray);

mySet.has('value1')     // returns true

// Use the spread syntax to transform a set into an Array.
console.log([...mySet]); // Will show you exactly the same Array as myArray

2 adalah string

const myArray = ['value1', 'value2', 'value3'];

// Use the regular Set constructor to transform an Array into a Set
const mySet = new Set(myArray);

mySet.has('value1')     // returns true

// Use the spread syntax to transform a set into an Array.
console.log([...mySet]); // Will show you exactly the same Array as myArray

3. Properti ini digunakan di

const myArray = ['value1', 'value2', 'value3'];

// Use the regular Set constructor to transform an Array into a Set
const mySet = new Set(myArray);

mySet.has('value1')     // returns true

// Use the spread syntax to transform a set into an Array.
console.log([...mySet]); // Will show you exactly the same Array as myArray

_4

const myArray = ['value1', 'value2', 'value3'];

// Use the regular Set constructor to transform an Array into a Set
const mySet = new Set(myArray);

mySet.has('value1')     // returns true

// Use the spread syntax to transform a set into an Array.
console.log([...mySet]); // Will show you exactly the same Array as myArray

5

Mengembalikan jumlah nilai dalam objek Set

const myArray = ['value1', 'value2', 'value3'];

// Use the regular Set constructor to transform an Array into a Set
const mySet = new Set(myArray);

mySet.has('value1')     // returns true

// Use the spread syntax to transform a set into an Array.
console.log([...mySet]); // Will show you exactly the same Array as myArray

7

Menyisipkan elemen baru dengan nilai tertentu ke objek Set, jika belum ada elemen dengan nilai yang sama di Set

// Use to remove duplicate elements from the array

const numbers = [2,3,4,4,2,3,3,4,4,5,5,6,6,7,5,32,3,4,5]

console.log([...new Set(numbers)])

// [2, 3, 4, 5, 6, 7, 32]

0

Menghapus semua elemen dari objek Set

// Use to remove duplicate elements from the array

const numbers = [2,3,4,4,2,3,3,4,4,5,5,6,6,7,5,32,3,4,5]

console.log([...new Set(numbers)])

// [2, 3, 4, 5, 6, 7, 32]

2

Menghapus elemen yang terkait dengan

// Use to remove duplicate elements from the array

const numbers = [2,3,4,4,2,3,3,4,4,5,5,6,6,7,5,32,3,4,5]

console.log([...new Set(numbers)])

// [2, 3, 4, 5, 6, 7, 32]

_3 dan mengembalikan pernyataan boolean apakah elemen berhasil dihapus atau tidak.

// Use to remove duplicate elements from the array

const numbers = [2,3,4,4,2,3,3,4,4,5,5,6,6,7,5,32,3,4,5]

console.log([...new Set(numbers)])

// [2, 3, 4, 5, 6, 7, 32]

4 akan mengembalikan

// Use to remove duplicate elements from the array

const numbers = [2,3,4,4,2,3,3,4,4,5,5,6,6,7,5,32,3,4,5]

console.log([...new Set(numbers)])

// [2, 3, 4, 5, 6, 7, 32]

5 sesudahnya

// Use to remove duplicate elements from the array

const numbers = [2,3,4,4,2,3,3,4,4,5,5,6,6,7,5,32,3,4,5]

console.log([...new Set(numbers)])

// [2, 3, 4, 5, 6, 7, 32]

6

Mengembalikan pernyataan boolean apakah suatu elemen hadir dengan nilai yang diberikan dalam objek Set atau tidak

// Use to remove duplicate elements from the array

const numbers = [2,3,4,4,2,3,3,4,4,5,5,6,6,7,5,32,3,4,5]

console.log([...new Set(numbers)])

// [2, 3, 4, 5, 6, 7, 32]

8

Mengembalikan objek iterator baru yang menghasilkan nilai untuk setiap elemen dalam objek Set dalam urutan penyisipan

const text = 'India';

const mySet = new Set(text);  // Set(5) {'I', 'n', 'd', 'i', 'a'}
mySet.size  // 5

//case sensitive & duplicate omission
new Set("Firefox")  // Set(7) { "F", "i", "r", "e", "f", "o", "x" }
new Set("firefox")  // Set(6) { "f", "i", "r", "e", "o", "x" }

_0

Mengembalikan objek iterator baru yang menghasilkan nilai untuk setiap elemen dalam objek Set dalam urutan penyisipan

const text = 'India';

const mySet = new Set(text);  // Set(5) {'I', 'n', 'd', 'i', 'a'}
mySet.size  // 5

//case sensitive & duplicate omission
new Set("Firefox")  // Set(7) { "F", "i", "r", "e", "f", "o", "x" }
new Set("firefox")  // Set(6) { "f", "i", "r", "e", "o", "x" }

_2

Alias untuk

const text = 'India';

const mySet = new Set(text);  // Set(5) {'I', 'n', 'd', 'i', 'a'}
mySet.size  // 5

//case sensitive & duplicate omission
new Set("Firefox")  // Set(7) { "F", "i", "r", "e", "f", "o", "x" }
new Set("firefox")  // Set(6) { "f", "i", "r", "e", "o", "x" }

0

const text = 'India';

const mySet = new Set(text);  // Set(5) {'I', 'n', 'd', 'i', 'a'}
mySet.size  // 5

//case sensitive & duplicate omission
new Set("Firefox")  // Set(7) { "F", "i", "r", "e", "f", "o", "x" }
new Set("firefox")  // Set(6) { "f", "i", "r", "e", "o", "x" }

_4

Mengembalikan objek iterator baru yang berisi larik

const text = 'India';

const mySet = new Set(text);  // Set(5) {'I', 'n', 'd', 'i', 'a'}
mySet.size  // 5

//case sensitive & duplicate omission
new Set("Firefox")  // Set(7) { "F", "i", "r", "e", "f", "o", "x" }
new Set("firefox")  // Set(6) { "f", "i", "r", "e", "o", "x" }

5 untuk setiap elemen dalam objek Set, dalam urutan penyisipan

Ini mirip dengan objek

const text = 'India';

const mySet = new Set(text);  // Set(5) {'I', 'n', 'd', 'i', 'a'}
mySet.size  // 5

//case sensitive & duplicate omission
new Set("Firefox")  // Set(7) { "F", "i", "r", "e", "f", "o", "x" }
new Set("firefox")  // Set(6) { "f", "i", "r", "e", "o", "x" }

7 , sehingga setiap kunci entri sama dengan nilainya untuk Set

const text = 'India';

const mySet = new Set(text);  // Set(5) {'I', 'n', 'd', 'i', 'a'}
mySet.size  // 5

//case sensitive & duplicate omission
new Set("Firefox")  // Set(7) { "F", "i", "r", "e", "f", "o", "x" }
new Set("firefox")  // Set(6) { "f", "i", "r", "e", "o", "x" }

_9

Memanggil

const array = Array
  .from(document.querySelectorAll('[id]'))
  .map((e) => e.id);

const set = new Set(array);
console.assert(set.size === array.length);

0 satu kali untuk setiap nilai yang ada di objek Set, dalam urutan penyisipan. Jika parameter

const array = Array
  .from(document.querySelectorAll('[id]'))
  .map((e) => e.id);

const set = new Set(array);
console.assert(set.size === array.length);

2 diberikan, parameter tersebut akan digunakan sebagai nilai

const array = Array
  .from(document.querySelectorAll('[id]'))
  .map((e) => e.id);

const set = new Set(array);
console.assert(set.size === array.length);

3 untuk setiap pemanggilan

const array = Array
  .from(document.querySelectorAll('[id]'))
  .map((e) => e.id);

const set = new Set(array);
console.assert(set.size === array.length);