javascript - 使用 javascript 循环有效返回数据

Question

最近，当我尝试从多循环语句返回数据时，我陷入了循环陷阱。

我正在创建个人资料过滤系统，该系统在获取人员后。它将过滤用户的好友。

 class UserFriend {

   analyseUserFriends(people, userfriends){
    people.forEach(person => {
        this.userfriends.forEach(friend => {
            if(person._id.toString() == friend._id.toString()){
                person.relationship = 0
            }else{
               person.relationship = 1;
             }
            return friend;//After loging friend the object of relationship is part of the member
        });
         return person;//After loging person the object of relationship is not part of the member
     });
  }
}

数据来自Mongo，与此类似

     userfriends:[ 
    {friend: mongoId},
    {friend: mongoId},
    {friend: mongoId},
    {friend: mongoId},
];
people: [
    {_id: mongoId}, 
    {_id: mongoId}, 
    {_id: mongoId}, 
    {_id: mongoId},
    {_id: mongoId}, 
    {_id: mongoId}, 
    {_id: mongoId}, 
    {_id: mongoId}
];

谢谢。

Answer 1

正如 @Leafyshark 在评论中提到的，这是 map 方法的一个用例。结合 find 方法，您应该能够实现此目的:

function analyseUserFriends (people, userFriends) {
    return people.map(person => {
        person.relationship = userFriends.find(x => x.friend.toString() === person._id.toString()) ? 1 : 0
        return person
    })
}