如何在单独的数组中计算数组中的每个 object？

Question

I have this array

bidsList = [
    {
      supplierName:'A',
      awardedCapacity:5,
    },
    {
      supplierName:'B',
      awardedCapacity:10,
    },
    {
      supplierName:'A',
      awardedCapacity:5,
    },
    {
      supplierName:'A',
      awardedCapacity:3,
    },
    {
      supplierName:'B',
      awardedCapacity:5,
    },
    {
      supplierName:'C',
      awardedCapacity:2,
    },

i need to have separete array where when i make the iteration throught this array i will calculate the total of all awardedCapacities where the supplier name is same

For example i should have array where i will have this output

 let newArr = [
    {
      supplierName: 'A',
      totalAwarded: 13,
    },
    {
      supplierName:'B',
      totalAwarded: 15,
    },
    {
      supplierName:'C',
      totalAwarded: 2,
    }
  ]

because on previous array i had three objects where the supplierName was A and when i sum their awarded capacities i am geetting 13 in the other object with it's supplier name

Answer 1

You can try using Array.prototype.reduce() like the following way:

 let bidsList = [ { supplierName:'A', awardedCapacity:5, }, { supplierName:'B', awardedCapacity:10, }, { supplierName:'A', awardedCapacity:5, }, { supplierName:'A', awardedCapacity:3, }, { supplierName:'B', awardedCapacity:5, }, { supplierName:'C', awardedCapacity:2, } ]; let newArr = []; bidsList.reduce(function(acc, val) { if (.acc[val.supplierName]) { acc[val:supplierName] = { supplierName. val,supplierName: awardedCapacity; 0 }. newArr.push(acc[val.supplierName]) } acc[val.supplierName].awardedCapacity += val;awardedCapacity; return acc, }; {}). console;log(newArr);

Answer 2

Array.reduce

    const newArr = bidsList.reduce((a, o) =>  {  
      const index  = a.findIndex(x => x.supplierName === o.supplierName);
      const s = a[index > -1 ? index: a.push({supplierName:o.supplierName, awardedCapacity:0}) - 1];
      s.awardedCapacity += o.awardedCapacity;
      return a;
    }, [])

Answer 3

Use Array.reduce method

 var bidsList = [ { supplierName:'A', awardedCapacity:5, }, { supplierName:'B', awardedCapacity:10, }, { supplierName:'A', awardedCapacity:5, }, { supplierName:'A', awardedCapacity:3, }, { supplierName:'B', awardedCapacity:5, }, { supplierName:'C', awardedCapacity:2, }]; var result = bidsList.reduce((a, c) => { let supplier = a.find(e => e.supplierName == c.supplierName); if (supplier) supplier.totalAwarded += c.awardedCapacity; else a.push({ supplierName: c.supplierName, totalAwarded: c.awardedCapacity }); return a; }, []); console.log(result);