基于现有数组和对象构造新的对象数组

Question

可能犯了一个愚蠢的错误，但我似乎无法弄清楚这一点。

基于现有的字符串数组，我想检查它们是否作为对象值存在于我的对象数组中。如果为真，则将它们推送到具有真值的新数组中，如果为假，也将它们推入新数组中，但具有假值。

到目前为止我的代码示例：

const answers = [12, 3, 16]
const quotes = [
{ id: 12, author: 'A'}, 
{ id: 4, author: 'B'}, 
{ id: 16, author: 'C'},  
]

let checkedQuotes = [];

answers.forEach((answer) => {
   ​quotes.find((quote) => (quote.id === answer
       ​&& checkedQuotes.push({
         ​id: quote.id,
         ​author: quote.author,
         ​correct: true,
       ​})
   ​));
 ​});

returns => [
  {id:12, author: 'A', correct: true}, 
  {id:16, author: 'C', correct: true}
]

这会将对象推送到我的新数组中，并且一切正常！问题是当我想添加错误的。我正在尝试这样做：

answers.forEach((answer) => {
    quotes.find((quote) => (quote.id === answer
      ? checkedQuotes.push({
        id: quote.id,
        author: quote.author,
        correct: true,
      })
      : checkedQuotes.push({
        id: quote.id,
        author: quote.author,
        correct: false,
      })
    ));
  });

returns => [
  {id:12, author: 'A', correct: true}, 
  {id:12, author: 'A', correct: false}, 
  {id:12, author: 'A', correct: false}
]

// would expect it to be: 
[
  {id:12, author: 'A', correct: true}, 
  {id:4, author: 'B', correct: false}, 
  {id:16, author: 'C', correct: true}
]

我在这里错过了什么？

Answer 1

我认为您需要遍历引号而不是答案，然后查看答案中的引号是否匹配。

const answers = [12, 3, 16];
const quotes = [
  { id: 12, author: 'A' }, 
  { id: 4, author: 'B' }, 
  { id: 16, author: 'C' },  
];

const res = quotes.map(
  (quote) => ({ ...quote, correct: answers.includes(quote.id) })
);

console.log(res);

Answer 2

这里是最少量循环的答案。

1. 使用 reduce 从答案数组 - {'value': true} 创建一个对象。
2. 循环遍历答案，同时检查第 1) 点创建的对象中的答案是否正确。

const answers = [12, 3, 16]
const quotes = [
{ id: 12, author: 'A'}, 
{ id: 4, author: 'B'}, 
{ id: 16, author: 'C'},  
]

const answersObj = answers.reduce(function(obj, answer) {
  obj[answer] = true;
  return obj;
}, {});

for (quote of quotes) {
  quote['correct'] = answersObj[quote.id] || false;
}

console.log(quotes)