检查嵌套数组中是否存在值

Question

我正在尝试检查嵌套数组中是否存在某个值。这是我正在处理的数据的样子：

[
    {
      name: 'bob',
      occupation: ['Teacher', 'Store Owner'],
    },
    {
      name: 'grace',
      occupation: ['Doctor'],
    },
]

我正在尝试查看职业值是否已经存在。这是我当前的代码：

const occupationExists = (value) => users.some((user) => user.occupation === value);

我知道这是行不通的，因为它没有访问数组中的值，但我该怎么做呢？任何帮助将不胜感激。

Answer 1

您还需要检查 occupation 以及 Array#includes。

const occupationExists = value => users.some(user =>
    user.occupation.includes(value)
);

Answer 2

let aoo = [
    {
      name: 'bob',
      occupation: ['Teacher', 'Store Owner'],
    },
    {
      name: 'grace',
      occupation: ['Doctor', 'Store Owner'],
    },
]

let fullOccupation = []

aoo.map(obj => {
  obj.occupation.map(occ => {
    const check = fullOccupation.includes(occ) 
          console.log(occ)
          if(!check)
          {
            fullOccupation.push(occ)
          }else{
                    alert(occ)

          }
  })
})

Answer 3

这应该可以解决问题，它 returns true/false 取决于职业是否存在。

let users = [
    {
      name: 'bob',
      occupation: ['Teacher', 'Store Owner'],
    },
    {
      name: 'grace',
      occupation: ['Doctor'],
    },
]


const occupationExists = (value) => {
    let res = users.filter((user) =>
        user.occupation.indexOf(value) != -1
    )
    return res.length > 0
}
let value = 'Doctor'
console.log(occupationExists(value))

Answer 4

这是 user.occupation === value 的问题：user.occupation 是一个字符串数组，而 value 是一个字符串，因此您无法比较两者。您可以按照@NinaScholz 的说明使用 Array#includes()，也可以使用另一个（内部）Array#some()，在其中您可以将字符串与字符串进行比较：job === value.

const users = [{name: 'bob',occupation: ['Teacher', 'Store Owner']}, {name: 'grace',occupation: ['Doctor']}];

//const occupationExists = value => users.some(user => user.occupation.includes(value)); //best answer

//Alternative answer
const occupationExists = value => users.some(
    user => user.occupation.some(job => job === value)
);

console.log( occupationExists('Teacher') );
console.log( occupationExists('Developer') );

检查嵌套数组中是否存在值

Check if value exists in nested array

javascript

arrays

data-structures

reactjs