Javascript lodash：按对象过滤和排除数组

我有一系列问题：

以及答案的

数组b

，其中属性

问题id

引用

数组a

的属性

id

：

[
  {id: 1, question_id: 2,name: "My Answer to Question 2"}
]

使用lodash，我想过滤

数组a

，排除引用它的所有答案，并期望得到以下输出：

[
  {id: 1,name: "Question 1"},
  {id: 3,name: "Question 3"},
]

简短的回答

---

不客气。仅供参考，这只能通过香草JS实现。所以，如果你只是为了这个而加载Lodash，最好只使用香草JS。

[
  {id: 1,name: "Question 1"},
  {id: 3,name: "Question 3"},
]

var questions = [
    {id: 1,name: "Question 1"},
    {id: 2,name: "Question 2"},
    {id: 3,name: "Question 3"},
];

var answers = [
    {id: 1, question_id: 2,name: "My Answer to Question 2"}
];

var filtered = _.filter(questions, isNotReferencedByAnyAnswer);

function isNotReferencedByAnyAnswer(question) {
    return _.findIndex(answers, {'question_id': question.id}) === -1;
}

arr = [
       {id: 1,name: "Question 1"},
       {id: 2,name: "Question 2"},
       {id: 3,name: "Question 3"},
]
arr1 = [
  {id: 1, question_id: 2,name: "My Answer to Question 2"}
]
_.differenceWith(arr, arr1, (arrVal, othVal) => arrVal.id === othVal.question_id)

// result

[ { id: 1, name: 'Question 1' }, { id: 3, name: 'Question 3' } ]