JavaScript中如何从对象数组筛选出指定ID集合的新数组？

基础实现 #

直接利用数组的filter方法结合includes判断，写法简洁直观：

const availAbleData = [{id:1,name:'user1'},{id:2,name:'user2'},{id:3,name:'user3'},{id:4,name:'user5'},{id:5,name:'user5'},{id:6,name:'user6'}];
const selectedIds=[1,2,3,4];

// 筛选id在selectedIds中的对象
const filteredData = availAbleData.filter(item => selectedIds.includes(item.id));

console.log(filteredData);
// 输出结果：
// [{id:1,name:'user1'},{id:2,name:'user2'},{id:3,name:'user3'},{id:4,name:'user5'}]

性能优化方案 #

如果selectedIds数组元素较多，推荐先把它转换成Set——因为Set的has方法查找时间复杂度是O(1)，比数组includes的O(n)效率更高：

const availAbleData = [{id:1,name:'user1'},{id:2,name:'user2'},{id:3,name:'user3'},{id:4,name:'user5'},{id:5,name:'user5'},{id:6,name:'user6'}];
const selectedIds=[1,2,3,4];

// 转换为Set提升查找性能
const idSet = new Set(selectedIds);
const filteredData = availAbleData.filter(item => idSet.has(item.id));

console.log(filteredData);
// 输出结果与基础实现一致

内容的提问来源于stack exchange，提问作者sourabhk