分解对象数组(es6)

Question

我想知道如何构造一个对象数组。我正在尝试从country数组中构造partner。项目要求partner是一个对象数组，即使每个obj只应该有一个合作伙伴国家。

arr = [
   { title: "Title A",
     desc: "Desc A",
     role: {role_desc: "Role Desc A", role_name: "Role A"},
     partner: [{country: "Brazil", region: "SA"}]
   },
   { title: "Title B",
     desc: "Desc B",
     role: {role_desc: "Role Desc B", role_name: "Role B"},
     partner: [{country: "US", region: "NA"}]
   }
]

我能够为除partner之外的所有字段填充数据表。

arr.map(
  ({ title, desc, role: {role_name}, partner: [{country}] }) => 
  ({ title, desc, role: {role_name}, partner: [{country}] })
);

我已经提到了Destructure object properties inside array for all elements和Destructuring an array of objects with es6，如果不首先转换数据，就不可能做到这一点。

如有任何帮助，我们将不胜感激(并对此表示歉意)。

Answer 1

由于一个同样简单的错误，我忽略了一个非常简单的答案：

arr.map(
  ({ title, desc, role: {role_name}, partner}) => 
  ({ title, desc, role: {role_name}, partner: (partner[0] && partner[0].country) || 'Undefined' })
);

数组中的每个项都不一定具有"country“属性。对于某些项，partner只是一个空数组。上述情况解决了这个问题。

我同意，如果partner只包含一个对象，那么使它成为数组是没有意义的。然而，客户需求。

Answer 2

当合作伙伴为空数组时，您只需使用默认值来处理该情况，

​

const arr = [{ title: "Title A",desc: "Desc A",role: {role_desc: "Role Desc A", role_name: "Role A"},partner: [{country: "Brazil", region: "SA"}]},{ title: "Title B",desc: "Desc B",role: {role_desc: "Role Desc B", role_name: "Role B"},partner: [{country: "US", region: "NA"}]},{ title: "Title C",desc: "Desc C",role: {role_desc: "Role Desc C", role_name: "Role C"},partner: []}]

const final = arr.map(
  ({ title, desc, role: {role_name}, partner}) => 
  ({ title, desc, role: {role_name}, partner:[ {country} = {country: undefined } ] })
);

console.log(final)

​

尽管如此，我们应该尽可能地保持代码的可读性，在这里，它变得非常困难，而不是试图多保留一行，我们应该选择让它更易读。

​

const arr = [{ title: "Title A",desc: "Desc A",role: {role_desc: "Role Desc A", role_name: "Role A"},partner: [{country: "Brazil", region: "SA"}]},{ title: "Title B",desc: "Desc B",role: {role_desc: "Role Desc B", role_name: "Role B"},partner: [{country: "US", region: "NA"}]},{ title: "Title C",desc: "Desc C",role: {role_desc: "Role Desc C", role_name: "Role C"},partner: []}]

const final = arr.map(
  ({ title, desc, role: {role_name}, partner}) => {
     let country = partner[0] && partner[0].country || undefined
    return { title, desc, role: {role_name}, partner:[ {country}] }
  }
);

console.log(final)

​