Implementation method:

let arr1 = [1, 2, 3, 4, 5, 6];

let arr2 = [2, 4, 6, 7, 8];

let arr3 = Array.from(new Set([...arr1, ...arr2])); Copy the code

Extending ES6 Set

A Set is like an array, but its member values are unique and unique.

 let set= new Set (,2,2,3,3,4 [1]); Set(4) {1, 2, 3, 4}Copy the code

Set operation method

Add (value): Adds a value and returns the Set function.

Delete (value): deletes a value.

Has (value): Returns a Boolean value indicating whether it is a member of a Set

Clear (): Clears all members

 set.add('1').add('a');

set.has(1); //true

set.has('1'); //true

set.has('a'); //true

set.delete('1');

set.clear(); Copy the code

Array.from converts a Set structure to an Array, which allows Array deduplicating

 ler arr = Array.from(set); Copy the code

Set traversal method

Keys (): Returns all key names

Values (): Returns all key values

Entries (): Returns all key-value pairs

ForEach (): callback function traversal

The keys, values, and entries methods all return traverser objects. Because the Set structure has no key name, only key value (that is, the key name and key value are the same value), the key and value methods behave exactly the same.

set.values();   //1, 2, 3, 4

set.keys();  //1, 2, 3, 4

set.entries();  //0: {1 => 1}1: {2 => 2}2: {3 => 3}3: {4 => 4}

set.forEach((item)=>console.log(item));Copy the code