javascript - 遍历对象，其中值是对象数组，并从对象数组的每个对象返回一个值

Question

如何从中获取所有 office 值并将其存储为简单数组？

var data = {
  'XYZ': [{
      office: 'xyz.in',
      reportName: 'payroll',
      event: 'open',
      timestamp: '02-12-2019 00:15:29'
    },
    {
      office: 'xyz.in',
      reportName: 'payroll',
      event: 'processed',
      timestamp: '02-12-2019 00:15:32'
    }
  ],
  'yyy': [{
      office: 'yyy.in',
      reportName: 'payroll',
      event: 'delivered',
      timestamp: '02-12-2019 00:15:29'
    },
    {
      office: 'yyy.in',
      reportName: 'payroll',
      event: 'open',
      timestamp: '02-12-2019 00:15:32'
    }
  ],
  'zzz': [{
      office: 'xyz.in',
      reportName: 'payroll',
      event: 'delivered',
      timestamp: '02-12-2019 00:15:29'
    },
    {
      office: 'xyz.in',
      reportName: 'payroll',
      event: 'open',
      timestamp: '02-12-2019 00:15:32'
    }
  ]
}

输出应该是这样的:

officesArray = ['xyz.in', 'yyy.in', 'xyz.in']

我的代码是

var Office = (Object.entries(grpDatas).flatMap(([k, v]) => (v.forEach(({office})=> office))))

它打印array of undefined。

Answer 1

使用 map 而不是 forEach 并且您正在访问 email 而不是 office:

var data = {
  'XYZ': [{
      office: 'xyz.in',
      reportName: 'payroll',
      event: 'open',
      timestamp: '02-12-2019 00:15:29'
    },
    {
      office: 'xyz.in',
      reportName: 'payroll',
      event: 'processed',
      timestamp: '02-12-2019 00:15:32'
    }
  ],
  'yyy': [{
      office: 'yyy.in',
      reportName: 'payroll',
      event: 'delivered',
      timestamp: '02-12-2019 00:15:29'
    },
    {
      office: 'yyy.in',
      reportName: 'payroll',
      event: 'open',
      timestamp: '02-12-2019 00:15:32'
    }
  ],
  'zzz': [{
      office: 'xyz.in',
      reportName: 'payroll',
      event: 'delivered',
      timestamp: '02-12-2019 00:15:29'
    },
    {
      office: 'xyz.in',
      reportName: 'payroll',
      event: 'open',
      timestamp: '02-12-2019 00:15:32'
    }
  ]
}

var Email = Object.values(data).flatMap(item => [...new Set(item.map(({office})=> office))])
console.log(Email)