How to create a date counter ? i tried it using reduce function

问题

using id, billStatus and tDate need to make a daycounter which counts date of days leads are received. Example => for id:"1" 2 Billable against 8th of may AND 3 Billable for 9th of may than day counter will become => 1+1 = 2

Note: if I get 1 lead or 7 leads for a single day daycount will be 1 and increment the next day when there will be any new lead on a new day.

 data: [
      { id: "1", billStatus: "Billable", tDate: "05/08/2020", dayCounter: 0 },
      { id: "1", billStatus: "Billable", tDate: "05/08/2020", dayCounter: 0 },
      { id: "1", billStatus: "Non-Billable", tDate: "05/08/2020", dayCounter: 0 },
      { id: "1", billStatus: "Billable", tDate: "05/09/2020", dayCounter: 6 },
      { id: "1", billStatus: "Non-Billable", tDate: "05/09/2020", dayCounter: 0 },
      { id: "1", billStatus: "Billable", tDate: "05/09/2020", dayCounter: 0 },
      { id: "1", billStatus: "Billable", tDate: "05/09/2020", dayCounter: 0 },
      { id: "3", billStatus: "Billable", tDate: "05/10/2020", dayCounter: 0 },
      { id: "2", billStatus: "Billable", tDate: "05/10/2020", dayCounter: 0 },
      { id: "2", billStatus: "Non-Billable", tDate: "05/10/2020", dayCounter: 0 },
      ],




retult:  
data: [
          { id: "1", dayCounter: 0 },
          { id: "2",  dayCounter: 2 },
          { id: "3", dayCounter: 1 }]

回答1:

You can check this solution. Though i'm not clear about your expected output. But hope it will provide you some idea.

const data = [
  { id: "1", billStatus: "Billable", tDate: "05/08/2020", dayCounter: 0 },
  { id: "1", billStatus: "Billable", tDate: "05/08/2020", dayCounter: 0 },
  { id: "1", billStatus: "Non-Billable", tDate: "05/08/2020", dayCounter: 0 },
  { id: "1", billStatus: "Billable", tDate: "05/09/2020", dayCounter: 6 },
  { id: "1", billStatus: "Non-Billable", tDate: "05/09/2020", dayCounter: 0 },
  { id: "1", billStatus: "Billable", tDate: "05/09/2020", dayCounter: 0 },
  { id: "1", billStatus: "Billable", tDate: "05/09/2020", dayCounter: 0 },
  { id: "3", billStatus: "Billable", tDate: "05/10/2020", dayCounter: 0 },
  { id: "2", billStatus: "Billable", tDate: "05/10/2020", dayCounter: 0 },
  { id: "2", billStatus: "Non-Billable", tDate: "05/10/2020", dayCounter: 0 },
];

const billableDates = data.reduce((res, obj) => {
  if (!res[obj.id]) {
    if (obj.billStatus === "Billable") {
      res[obj.id] = { dates: new Set() };
      res[obj.id].dates.add(obj.tDate);
    }
  } else {
    res[obj.id].dates.add(obj.tDate);
  }
  return res;
}, {});

const modifiedData = data.reduce((store, obj) => {
  if (!store[obj.id] && obj.billStatus === "Billable") {
    store[obj.id] = obj;
    store[obj.id].dayCounter = billableDates[obj.id].dates.size;
    store[obj.id].dates = [...billableDates[obj.id].dates];
  }
  return store;
}, {});

console.log(Object.values(modifiedData));

来源：https://stackoverflow.com/questions/61785210/how-to-create-a-date-counter-i-tried-it-using-reduce-function

标签

arrays

MapReduce

counter

counting