Lodash从对象数组中查找公用值

Question

从对象数组中找到常用值并为它们加尾音

尝试使用lodash groupBy

var data =[
  {
    "dc": 1,
    "effDate": "1/2/2019",
    "expDate": "1/2/2019",
    "rate": 1,
    "minCharge": 2
  },
  {
    "dc": 1,
    "effDate": "1/2/2019",
    "expDate": "1/2/2019",
    "rate": 2,
    "minCharge": 6
  },
  {
    "dc": 1,
    "effDate": "1/2/2019",
    "expDate": "1/2/2019",
    "rate": 4,
    "minCharge": 7
  }
]

var expectedResult=[
  {
    "dc": 1,
    "effDate": "1/2/2019",
    "expDate": "1/2/2019",
    "rateCharge": [
      {
        "rate": 1,
        "minCharge": 2
      },
      {
        "rate": 2,
        "minCharge": 6
      },
      {
        "rate": 4,
        "minCharge": 7
      }
    ]
  }
]

在数据dc中，effDate，expDate是相同的，因此我需要将常见内容保留为平面结构，并将重复项移到rateCharge中。

var expectedResult=uniqBy(data,(val1.rate,val2.rate) => {
  val1.rate!=val2.rate;    
});

我尝试使用lodash uniqBy属性，但没有得到预期的结果。

Answer 1

您需要按effDate对项目进行effDate ，然后使用_.pick() / _.omit() ， _.map()并将_.uniqBy()与rate作为唯一标识符。

打字稿示例 （打开浏览器控制台）

 const { flow, partialRight: pr, groupBy, map, head, pick, omit, uniqBy } = _ const EFF_DATA = 'effDate' const baseProps = ['dc', EFF_DATA, 'expDate'] const fn = flow( pr(groupBy, EFF_DATA), pr(map, g => ({ ...pick(head(g), baseProps), rateCharge: uniqBy(map(g, pr(omit, baseProps)), 'rate') })) ) const data = [{"dc":1,"effDate":"1/2/2019","expDate":"1/2/2019","rate":1,"minCharge":2},{"dc":1,"effDate":"1/2/2019","expDate":"1/2/2019","rate":2,"minCharge":6},{"dc":1,"effDate":"1/2/2019","expDate":"1/2/2019","rate":4,"minCharge":7}] const result = fn(data) console.log(result) 

 <script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.11/lodash.min.js"></script> 

如果您已经导入了整个lodash软件包，则可以使用链接：

 const { flow, partialRight: pr, groupBy, map, head, pick, omit, uniqBy } = _ const EFF_DATA = 'effDate' const baseProps = ['dc', EFF_DATA, 'expDate'] const data = [{"dc":1,"effDate":"1/2/2019","expDate":"1/2/2019","rate":1,"minCharge":2},{"dc":1,"effDate":"1/2/2019","expDate":"1/2/2019","rate":2,"minCharge":6},{"dc":1,"effDate":"1/2/2019","expDate":"1/2/2019","rate":4,"minCharge":7}] const result = _(data) .groupBy(EFF_DATA) .map(g => ({ ...pick(head(g), baseProps), rateCharge: uniqBy(map(g, pr(omit, baseProps)), 'rate') })); console.log(result) 

 <script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.11/lodash.min.js"></script> 

和lodash / fp版本：

 const { flow, groupBy, map, head, pick, omit, uniqBy, assoc } = _; const EFF_DATA = 'effDate' const baseProps = ['dc', EFF_DATA, 'expDate']; const fn = flow( groupBy(EFF_DATA), map(g => assoc( 'rateCharge', flow(map(omit(baseProps)), uniqBy('rate'))(g), pick(baseProps, head(g)) )) ) const data = [{"dc":1,"effDate":"1/2/2019","expDate":"1/2/2019","rate":1,"minCharge":2},{"dc":1,"effDate":"1/2/2019","expDate":"1/2/2019","rate":2,"minCharge":6},{"dc":1,"effDate":"1/2/2019","expDate":"1/2/2019","rate":4,"minCharge":7}] const result = fn(data) console.log(result) 

 <script src='https://cdn.jsdelivr.net/g/lodash@4(lodash.min.js+lodash.fp.min.js)'></script>