将键/值对添加到数组数组中的对象？

Question

给定以下结构：

const data = {
  "show": "Family Guy",
  "characters": [
      [{name: 'Peter', age: 40, city: 'Quahog'}],
      [{name: 'Louis', age: 30}],
      [{name: 'Chris', age: 16}],
      [{name: 'Stewie', age: 1}]
    ]
 }

我们如何添加每个字符city的密钥/值对：'quahog'，因此输出看起来如下：

const item = {
  "show": "Family Guy",
  "characters": [
      [{name: 'Peter', age: 40, city: 'Quahog'}],
      [{name: 'Louis', age: 30, city: 'Quahog'}], // city added
      [{name: 'Chris', age: 16, city: 'Quahog'}], // city added
      [{name: 'Stewie', age: 1, city: 'Quahog'}]  // city added
    ]
 }

我们尝试使用：

let city = data.characters.[0][0].city;
costs = _.map(items, (itemArray) => {
            items = _.map(itemArray, (item) => {
              if(!item.city) {
                item.city = city;
              }
        });

但是它不按预期工作，我们可以t获得所需的输出。有什么想法如何实现这一目标？

Answer 1

这是用.duce（）进行操作的另一种方法：

const data = {
  "show": "Family Guy",
  "characters": [
  [{name: 'Peter', age: 40, city: 'Quahog'}],
  [{name: 'Louis', age: 30}],
  [{name: 'Chris', age: 16}],
  [{name: 'Stewie', age: 1}]
]
 };

data.characters.reduce((a,c)=>
 (c[0].city=a[0].city,a));

console.log(data);

当使用.duce（）而无需第二个参数时，它将选择第一个数组元素作为初始值，然后将其用作模板，以将.city属性复制到所有其他元素。丢弃.Reduce（）方法的实际返回值，但输入数组本身（data）在过程中进行了修改，然后在Console中显示.log（）表达式。

Answer 2

尝试这个

let city = data.characters.[0][0].city;
let newdata = [];
data.characters.map(items, (itemArray) => {
        items = _.map(itemArray, (item) => {
          if(item.city === undefined) {
              newdata.push({...item , city});
          } else { 
           newdata.push({...item});
           }

    })
    costs = {...newdata}

Answer 3

您可以在没有Lodash的情况下这样做

const data = {
  "show": "Family Guy",
  "characters": [
      [{name: 'Peter', age: 40, city: 'Quahog'}],
      [{name: 'Louis', age: 30}],
      [{name: 'Chris', age: 16}],
      [{name: 'Stewie', age: 1}]
    ]
 }

const chars = data.characters.map((x)=>{

    return {...x[0] , city : x[0].city ? x[0].city : city} 
})

const items = {...data , characters : chars};

Answer 4

const { city } = data.characters.find(([item]) => !!item.city?.length)[0];

const newData = {
    ...data,
    characters: data.characters.map(([char]) => [{ ...char, city }])
};

Answer 5

不确定拥有这些单个项目数组的原因，但是该解决方案将完成工作（我建议您查看创建此数据格式的过程，这有点奇怪）

const data = {
  "show": "Family Guy",
  "characters": [
      [{name: 'Peter', age: 40, city: 'Quahog'}],
      [{name: 'Louis', age: 30}],
      [{name: 'Chris', age: 16}],
      [{name: 'Stewie', age: 1}]
    ]
 }
 
 const city = data.characters.find(characters => characters.find(character => character.city))[0].city

const dataWithCities = {
 ...data,
 characters: data.characters.map(characters => characters.map(character => character.city ? character : {...character, city}))
 }
 
 console.log(dataWithCities)