Set 可以很容易地实现并集(Union)、交集(Intersect)和差集(Difference)。 let a = new Set([1, 2, 3]); let b = new Set([4, 3, 2]); // 并集 let union = new Set([...a, ...b]); console.log(union) // 交集 let intersect = new Set([...a].filter(x => b.has(x))); console.log(intersect ) // 差集 let difference = new Set([...a].filter(x => !b.has(x))); console.log(difference )