Question

我有来自服务器端的JSON数据，但不是我想要的。我的json数据有多个循环，我想将其转换为单个循环。

我正在获取JSON

    [
  [
    "Year",
    "2018-9",
    "2017-9"
  ],
  [
    "JAYANAGAR",
    "2018-9",
    857
  ],
  [
    "MALLESHWARAM",
    "2018-9",
    169
  ],
  [
    "KOLAR",
    "2018-9",
    178
  ],
  [
    "JAYANAGAR",
    "2017-9",
    635
  ],
  [
    "MALLESHWARAM",
    "2017-9",
    56
  ],
  [
    "KOLAR",
    "2017-9",
    90
  ]
]

在这里，例如jayanagar malleshwaram和kolar会重复我的不同约会

我正在尝试将其转换为类似的内容

 [
  [
    "Year",
    "2018-9",
    "2017-9"
  ],
  [
    "Jayanagar",
    857,
    635
  ],
  [
    "Malleshwaram",
    169,
    56
  ],
  [
    "Kolar",
    178,
    90
  ]
]

在我的第一个json数据中，重复的日期是2018-8和2017-8

我想映射数据并将其简化为想要获取的数据。

我知道可以使用JavaScript来完成，但是我不知道该怎么做。

Answer 1

假设每个“位置”的数据按正确的顺序排列，则可以像这样使用reduce和Object.values()：

const input=[["Year","2018-9","2017-9"],["JAYANAGAR","2018-9",857],["MALLESHWARAM","2018-9",169],["KOLAR","2018-9",178],["JAYANAGAR","2017-9",635],["MALLESHWARAM","2017-9",56],["KOLAR","2017-9",90]]

const merged = input.reduce((acc, arr) => {
  const [city, year, value] = arr;
  
  if (city === "Year")
    acc[city] = arr
  else {
    acc[city] = acc[city] || [city]
    acc[city].push(value)
  }
  
  return acc;
}, {})

const output = Object.values(merged)
console.log(output)

Answer 2

您可以将数据分组以创建所需的结构

const first = foo.shift();
const res = Array.from(
  foo.reduce((a, [t,_,n]) => a.set(t, (a.get(t) || []).concat(n)), new Map)
).map(e => [].concat(...e));
res.unshift(first);
console.log(res);

<script>
const foo = [
  [
    'Year',
    '2018-9',
    '2017-9'
  ],
  [
    'JAYANAGAR',
    '2018-9',
    857
  ],
  [
    'MALLESHWARAM',
    '2018-9',
    169
  ],
  [
    'KOLAR',
    '2018-9',
    178
  ],
  [
    'JAYANAGAR',
    '2017-9',
    635
  ],
  [
    'MALLESHWARAM',
    '2017-9',
    56
  ],
  [
    'KOLAR',
    '2017-9',
    90
  ]
];
</script>

Answer 3

const dataSet = [
  [
    "Year",
    "2018-9",
    "2017-9"
  ],
  [
    "JAYANAGAR",
    "2018-9",
    857
  ],
  [
    "MALLESHWARAM",
    "2018-9",
    169
  ],
  [
    "KOLAR",
    "2018-9",
    178
  ],
  [
    "JAYANAGAR",
    "2017-9",
    635
  ],
  [
    "MALLESHWARAM",
    "2017-9",
    56
  ],
  [
    "KOLAR",
    "2017-9",
    90
  ]
];

const dataBody = dataSet.slice(1);
const transformedDataBody = dataBody.reduce(function (currentValue, nextValue){
    currentValue[nextValue[0]] = currentValue[nextValue[0]] || [nextValue[0]];
    currentValue[nextValue[0]].push(nextValue[2]);
    return currentValue; 
}, {})
let finalDataSet = [ dataSet[0] ];
Object.keys(transformedDataBody).map(function(key){
	finalDataSet.push(transformedDataBody[key]);
})
console.log(finalDataSet);

这就是你想要的吗？

如何在一个数组中循环JSON数据

3 个答案: