如何返回对象数组中的所有对象？

Question

我正在尝试获取对象数组中的所有对象。 我试过在线搜索解决方案并获得了一些有用的提示。 但是，它只返回一个对象，而不是数组中的所有对象。 我似乎无法弄清楚为什么？

对象数组：

[{"id":"_f939IxLRjn0YVvOEg5SR","type":"multiple","category":"Entertainment: Video Games","question":"Which Sonic the Hedgehog game was originally supposed to be packaged with Sonic 3, but was cut in half due to time constraints?","correct_answer":"Sonic & Knuckles","incorrect_answers":["Sonic 2","Sonic CD","Sonic 3D Blast"]},{"id":"84LQQOeMZqeqYweGXKZ47","type":"multiple","category":"General Knowledge","question":"Which American-owned brewery led the country in sales by volume in 2015?","correct_answer":"D. G. Yuengling and Son, Inc","incorrect_answers":["Anheuser Busch","Boston Beer Company","Miller Coors"]}]

Array.reduce 代码：

const [quizObj, setQuizObj] = useState({});

useEffect(() => {
    setQuizObj(() => {
      return allQuiz.reduce((obj, item) => Object.assign(obj, { ...item }), {});
    });
  }, [allQuiz]);

控制台日志 output：

{"id":"84LQQOeMZqeqYweGXKZ47","type":"multiple","category":"General Knowledge","question":"Which American-owned brewery led the country in sales by volume in 2015?","correct_answer":"D. G. Yuengling and Son, Inc","incorrect_answers":["Anheuser Busch","Boston Beer Company","Miller Coors"]}

所需的 output：

{item: {"id":"_f939IxLRjn0YVvOEg5SR","type":"multiple","category":"Entertainment: Video Games","question":"Which Sonic the Hedgehog game was originally supposed to be packaged with Sonic 3, but was cut in half due to time constraints?","correct_answer":"Sonic & Knuckles","incorrect_answers":["Sonic 2","Sonic CD","Sonic 3D Blast"]}, {"id":"84LQQOeMZqeqYweGXKZ47","type":"multiple","category":"General Knowledge","question":"Which American-owned brewery led the country in sales by volume in 2015?","correct_answer":"D. G. Yuengling and Son, Inc","incorrect_answers":["Anheuser Busch","Boston Beer Company","Miller Coors"]}} 

Answer 1

如果您试图将对象数组转换为单个 object，那么应该有一种方法可以使用 output object 中的唯一键来标识每个数组项。

假设：每个数组项都有一个id属性，并且每个项的id都是唯一的。 如果id不唯一，则数据可能会被覆盖。

useEffect(() => {
    const combinedObj = {};

    allQuiz.forEach((obj) => {
      combinedObj[obj.id] = { ...obj };
    });
  
    return combinedObj; 
});

我有意使用.forEach而不是.reduce因为它更容易阅读。 但是您当然可以坚持使用.reduce来获得相同的结果。