Cara menggunakan set di javascript

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

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

Menghapus semua elemen dari objek Set

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

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

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

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

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

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

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); 0