如何過濾 Object 的數組並檢查特定鍵是否在數組中具有值

Question

我有這個對象數組：

const Books = [
  {title:'Book 1', Date: '12/12/2000'},
  {title:'Book 2', Date: '12/12/2001'},
  {title:'Book 3', Date: '12/12/2003'},
  {title:'Book 4', Date: '12/12/2003'}
]

我有這一系列選定的書籍：

 const selectedBooks = ['Book1','Book4']

是否有可能獲得以下結果：

 const filteredBooks = [
     {title:'Book 1', Date: '12/12/2000'},
     {title:'Book 4', Date: '12/12/2003'}
 ]

lodash 或 ES6 中是否有實現它的方法？

Answer 1

您可以將Array.prototype.filter與Array.prototype.includes一起使用：

 const Books = [ { title: 'Book 1', Date: '12/12/2000' }, { title: 'Book 2', Date: '12/12/2001' }, { title: 'Book 3', Date: '12/12/2003' }, { title: 'Book 4', Date: '12/12/2003' } ] const selectedBooks = ['Book 1', 'Book 4'] const filteredBooks = Books.filter(book => selectedBooks.includes(book.title)); console.log(filteredBooks);

Answer 2

您可以filter selectedBooks includes其title的所有元素：

const filteredBooks = Books.filter(book => selectedBooks.includes(book.title))

filter返回給定回調返回真實值的所有條目， includes將告訴您數組是否包含給定值。

Answer 3

是的，試試數組過濾運算符

const filteredBooks = Books.filter(({title}) => selectedBooks.includes(title))

Answer 4

我假設selectedBooks中的項目將與filteredBooks中的title匹配。 如果沒有，您將需要一些方法來 map 這些值。

您需要Array.prototype.filter和Array.prototype.indexOf的組合。

const filteredBooks = Books.filter(book => selectedBooks.indexOf(book.title) !== -1)

Answer 5

 const books = [ { title: 'Book 1', Date: '12/12/2000' }, { title: 'Book 2', Date: '12/12/2001' }, { title: 'Book 3', Date: '12/12/2003' }, { title: 'Book 4', Date: '12/12/2003' } ]; const selectedBooks = ['Book 1', 'Book 4']; const filteredBooks = _.filter(books, book => _.includes(selectedBooks, book.title)); console.log(filteredBooks);

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