如何将数据推送到嵌套数组中的子数组？

Question

试图构建一个数组，该数组输出数据如下：

• 医疗保健 -数据驱动的洞察力，以改善医疗保健 -城市分析
• 运输 -城市分析
• 城市 -城市分析

我尝试过循环使用“专门知识”/“文本”，但我无法让它们一起工作，从而在console.log中获得所需的输出

任何和所有的帮助都将不胜感激。

    var items = [{
            "item": {
                "id": 0,
                "sector": 'Data',
                "expertise": ["Healthcare"],
                "text": "Data-driven insights to improve healthcare"
            }
        },
        {
            "item": {
                "id": 1,
                "sector": 'Data',
                "expertise": ["Healthcare", "Transport", "Cities"],
                "text": "Urban Analytics"
            }
        }
    }];

    var array = [];

    for (var i = 0; i < items.length; i++) {

        var arr = [{
            'title': items[i].item.sector,
            'items': []
        }];

        for (var j = 0, b = items[i].item.expertise.length; j < b; j++) {
            if (items[i].item.expertise[j] == expertise) {

                arr[0]['items'].push({
                    'list': items[i].item.text
                });

            }
        }

        array.push(arr);

    }

    console.log(array);

Answer 1

我首先要建立一个相关专业知识和文本列表的对象，然后输出您想要的任何内容。例如：

​

var items = [{
  "item": {
    "id": 0,
    "sector": 'Data',
    "expertise": ["Healthcare"],
    "text": "Data-driven insights to improve healthcare"
  }
}, {
  "item": {
    "id": 1,
    "sector": 'Data',
    "expertise": ["Healthcare", "Transport", "Cities"],
    "text": "Urban Analytics"
  }
}]
    
const obj = items.reduce((res, { item }) => {
  item.expertise.forEach(e => {
    res[e] = res[e] || []
    if(res[e].indexOf(item.text) < 0){ res[e].push(item.text) }
  })
  return res
}, {})

Object.keys(obj).forEach(k => {
  console.log(k)
  obj[k].forEach(text => console.log(`-- ${text}`))
})

​

Answer 2

你应该用地图

const array =  items.map(el => ({
    text: el.item.sector,
    items: [...el.item.expertise, {
        list : el.item.text
    }]
});

Answer 3

这里有另一种使用reduce()的方法，也可以使用destructuring和spread operator

​

var items = [
  {
    "item": {
      "id": 0,
      "sector": 'Data',
      "expertise": ["Healthcare"],
      "text": "Data-driven insights to improve healthcare"
    }
  },
  {
    "item": {
      "id": 1,
      "sector": 'Data',
      "expertise": ["Healthcare", "Transport", "Cities"],
      "text": "Urban Analytics"
    }  
  }
];

let res = items.reduce((acc, {item: {expertise, text}}) =>
{
     expertise.forEach(x => acc[x] = [...(acc[x] || []), text]);
     return acc;
}, {});


Object.entries(res).forEach(([k, v]) =>
{
    console.log(k + "\n->" + v.join("\n->"));
});

​