基础知识

创建Set

let v = new Set();

// 通过传入数组方式创建
let v = new Set([1,2,3,3,5]);

添加元素

let v = new Set()
v.add(1)

删除元素

let v = new Set([1,2,3,5])
v.delete(5)

获取Set中元素个数

let v = new Set([1,2,3,5])
console.log(v.size);

判断Set中是否包含某个元素

使用has方法:

let v = new Set([1,2,3,5])
console.log(v.has(5));

遍历Set

// forEach
let v = new Set([1,2,3,5])
v.forEach(t=>{
    console.log(t)
})

// for of
for(let t of v) {
    console.log(t)
}

将Set转换成数组

let v = new Set([1,2,3,5])
let arr = Array.from(v);

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