如何将javascript对象数组从一种格式排列为另一种格式？

Question

我觉得这是一个非常简单的答案，但我很难弄明白。

我想把这个对象数组：

[{
    client: 'lalala@email.com',
    amount: 0,
    date: '2018-12'
},
{
    client: 'lalala@email.com',
    amount: '30',
    date: '2018-11'
}, {
    client: 'lalala@email.com',
    amount: '5',
    date: '2018-10'
}]

如下所示：

[{
    client: 'lalala@email.com',
    '2018-12': 0,
    '2018-11': '30',
    '2018-10': '5'
}]

我一直在尝试着使用reduce()函数，但是没有得到任何结果。

感谢您能抽出时间来。

Answer 1

reduce是正确的方法-以下是如何做到这一点：

​

const data = [{
    client: 'lalala@email.com',
    amount: 0,
    date: '2018-12'
},
{
    client: 'lalala@email.com',
    amount: '30',
    date: '2018-11'
}, {
    client: 'lalala@email.com',
    amount: '5',
    date: '2018-10'
}]

const result = data.reduce((memo, {client, date, amount}) => {
  memo.client = client;
  memo[date] = amount;
  return memo;
}, {});

console.log(result)

​

Answer 2

使用Array.prototype.reduce，这将会起作用：

​

const a = [{
    client: 'lalala@email.com',
    amount: 0,
    date: '2018-12'
}, {
    client: 'lalala@email.com',
    amount: '30',
    date: '2018-11'
}, {
    client: 'lalala@email.com',
    amount: '5',
    date: '2018-10'
}]

const b = a.reduce((acc, {date, amount}) => {
  return { ...acc, [date]: amount }
}, { client: a[0].client })

console.log([b])

​

Answer 3

因为客户机始终是相同的，所以可以在reduce()中很好地使用Object.assign

​

const data = [{client: 'lalala@email.com',amount: 0,date: '2018-12'},{client: 'lalala@email.com',amount: '30',date: '2018-11'}, {client: 'lalala@email.com',amount: '5',date: '2018-10'}]

const result = data.reduce((obj, {client, date, amount}) => 
    Object.assign(obj, {client, [date]:amount}), {});

console.log([result])

​