Array and collection conversion
Array to collection
let arr = ["A", "B", "C", "A", "C", "C", "D"];
let set = new Set(arr);
console.log(set);
//Set to array
arr = [...set];
console.log(arr);
//The attribute collection name of the collection. size is the length of the collection
console.log(set.size);
ES6 collection
Multiple data can be stored without duplicate data (congruent matching)
Declare collection (create collection)
let set = new Set();
Collection properties and methods
add add data
Note: add will return the new collection after adding (chain call)
set.add(2).add(3).add(4).add(true);
console.log(set);
Empty collection
set.clear();
console.log(set);//{}
delete
Writing format: collection name.delete (deleted content)
set.delete(2);
console.log(set); //{3,4,true}
Find
Writing format: collection name.has (search content) return Boolean
console.log(set.has(2)); //false
console.log(set.has(3)); //true
console.log(set);
for (let items of set.keys()) {
console.log(`keys:${items}`);
}
for (let items of set.values()) {
console.log(`values:${items}`);
}