关于javascript:js-map结构和数组互相转换

1.map 构造转换为数组并合并数据；

// map 转数组
const mapData = {
  '2024-03-04': {
    detail: [{ titId: '1', name: 'aaa', age: 16},
      {titId: '2', name: 'ccc', age: 17},
    ]
   },
   '2024-03-05': {
     detail: [{ titId: '1', name: 'bbb', age: 18},
       {titId: '2', name: 'ddd', age: 19},
     ]
   }
 }
 let arrayData = []
 this.dateDetail = [{ 'titId': '1', 'titName': 'titName1'},
   {'titId': '2', 'titName': 'titName2'}
 ]
 for(let i in mapData) {mapData[i].detail.forEach(item => {item.date = i})
    arrayData.push(mapData[i])
 }
 console.log(arrayData)
 arrayData.forEach((item, index) => {
   // 数据处理
   item.detail.forEach((item1, index1) => {item1[`date`+(index+1)] = item1.date
     item1[`name`+(index+1)] = item1.name
     item1[`age`+(index+1)] = item1.age
     delete item1.date
     delete item1.name
     delete item1.age
     // 合并数据
     this.dateDetail.forEach((item2, index2) => {if(item2.titId === item1.titId) {let mergedObj = {...item2, ...item1}
         this.dateDetail.splice(index2, 1, mergedObj)
       }
     })
   })
  })
  console.log(this.dateDetail)
  // 打印后果为：// [//    { titId: '1', 'titName': 'titName1', date1: '2024-03-04', date2: '2024-03-05', name1: 'aaa', name2: 'bbb', age1: 16, age2: 18},
  //    {titId: '2', 'titName': 'titName2', date1: '2024-03-04', date2: '2024-03-05', name1: 'ccc', name2: 'ddd', age1: 17, age2: 19},
  // ]

2.a 数组转 map

const array = [{ titId: '1', 'titName': 'titName1', date1: '2024-03-04', date2: '2024-03-05', name1: 'aaa', name2: 'bbb', age1: 16, age2: 18},
  {titId: '2', 'titName': 'titName2', date1: '2024-03-04', date2: '2024-03-05', name1: 'ccc', name2: 'ddd', age1: 17, age2: 19}
]
const mapData = {}
array.forEach(item => {for (let key in item) {console.log(item[key], key, key.slice(4))
    if (key.indexOf('date') > -1) {const keyNew = item[key];
      const index = key.slice(4)
      if (!mapData[keyNew]) {mapData[keyNew] = []}
      mapData[keyNew].push({
        titId: item.titId,
        name: item[`name`+index],
        age: item[`age`+index],
      })
    }
  }
})
console.log(mapData)
// 打印后果为：//{
//'2024-03-04': [//    { titId: '1', name: 'aaa', age: 16},
//    {titId: '2', name: 'ccc', age: 17},
//],
//'2024-03-05': [//    { titId: '1', name: 'bbb', age: 18},
//    {titId: '2', name: 'ddd', age: 19},
//]