Question

请我是新手。我搜寻了一下，看到的东西让我感到困惑。

如何减少数组中的重复项并将重复键的值添加到唯一的键中，如下所示。

我想要像arrayA

let arrayA = [
  { name: "temperature", data: {"2000-09-26": 82} },
  { name: "temperature", data: {"1997-03-08": 71} },
  { name: "current", data: {"1993-08-11": 79} },
  { name: "frequency", data: {"2004-01-17": 16} },
  { name: "current", data: {"1997-02-14": 65} }
]

let arrayB = [
  { name: "temperature", data: {"2000-09-26": 82, "1997-03-08": 71} },
  { name: "current", data: {"1993-08-11": 79, "1997-02-14": 65} },
  { name: "frequency", data: {"2004-01-17": 16} }
]

Answer 1

您可以使用array#reduce和Object.values()。创建name的哈希，并为给定的data添加name值。然后使用Object.values()从对象获取值。

let arrayA = [ { name: "temperature", data: {"2000-09-26": 82} }, { name: "temperature", data: {"1997-03-08": 71} }, { name: "current", data: {"1993-08-11": 79} }, { name: "frequency", data: {"2004-01-17": 16} }, { name: "current", data: {"1997-02-14":
65} } ],
    result = Object.values(arrayA.reduce((r,{name, data}) => {
      r[name] = r[name] || {name, data: {}};
      Object.assign(r[name].data, data);
      return r;
    },{}));
console.log(result);

Answer 2

您在这里

let arrayB = arrayA.reduce((acc, curr) => {

    const found = acc.find(i => i.name === curr.name)
    if (found) {
        // If this object is already there, merge their `data` property 
        Object.assign(found.data, curr.data)
    } else {
        // Otherwise add to the accumulator (`acc`)
        acc.push(curr)    
    }

    return acc
}, [])

关于reduce函数的参考： https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/reduce

Answer 3

var arrayA = [ { name: "temperature", data: {"2000-09-26": 82} }, { name: "temperature", data: {"1997-03-08": 71} }, { name: "current", data: {"1993-08-11": 79} }, { name: "frequency", data: {"2004-01-17": 16} }, { name: "current", data: {"1997-02-14": 65} } ]
var arrayB=_.map(_.groupBy(arrayA, 'name'),function(list){
    
    return _.reduce(list,function(nObj,obj){
                    if(nObj.data && _.difference(_.keys(nObj.data),_.keys(obj.data))){
                         nObj.data=_.assign(nObj.data,obj.data)
                    }else{
                       nObj=obj
                    }
                  return nObj
               },{})
})
console.log(arrayB)

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.5.1/lodash.js"></script>

过滤重复的键

3 个答案: