how can i get sum of all the qty from nested array object

Question

I want to get sum of the qty values from the data. I tried, but I am only getting the total qty for the first item in the array.

I just want the result 10 from below (4 + 5 + 0 + 1)

let xyz = [{
    catid: '1',
    catName: 'abc',
    product: [{
        id: 1,
        qty: 4,
      },
      {
        id: 2,
        qty: 5,
      }
    ]
  },
  {
    catid: '2',
    catName: 'efg',
    product: [{
        id: 3,
        qty: 0,
      },
      {
        id: 4,
        qty: 1,
      }
    ]
  }
]

Answer 1

To do what you require you can use reduce() . You will need to nest two reduce() calls, one to sum the inner qty for each product, then another to sum the total for all products:

 let xyz = [ {catid: "1", catName: "abc", product: [{ id: 1, qty: 4 }, { id: 2, qty: 5 }]},{ catid: "2", catName: "efg", product: [{ id: 3, qty: 0 },{ id: 4, qty: 1 }]}]; var total = xyz.reduce((t0, o) => t0 + o.product.reduce((t1, prod) => t1 + prod.qty, 0), 0); console.log(total);

Answer 2

Uglier way with 2 forEach..

 let xyz = [{ catid: '1', catName: 'abc', product: [{ id: 1, qty: 4, }, { id: 2, qty: 5, } ] }, { catid: '2', catName: 'efg', product: [{ id: 3, qty: 0, }, { id: 4, qty: 1, } ] } ] let sum = 0; xyz.forEach(element => { element.product.forEach(product => { sum += product['qty']; }); }); console.log(sum);

Answer 3

let totalqTy = 0;
xyz.forEach(o => {
  totalqTy += o.product.map(p => p.qty).reduce(((previousValue, currentValue) => previousValue + currentValue));
});

Answer 4

Lodash fp if you don't mind

 const xyz = [ {catid: "1", catName: "abc", product: [{ id: 1, qty: 4 }, { id: 2, qty: 5 }]},{ catid: "2", catName: "efg", product: [{ id: 3, qty: 0 },{ id: 4, qty: 1 }]}]; const result = _(xyz).flatMap('product').sumBy('qty'); console.log(result);

 .as-console-wrapper { max-height: 100%;important: top: 0 }

 <script src="https://cdn.jsdelivr.net/npm/lodash@4.17.21/lodash.min.js"></script>

Answer 5

You need a nested loop. Array#reduce will do the trick.

 let xyz = [{ catid: '1', catName: 'abc', product: [{ id: 1, qty: 4, }, { id: 2, qty: 5, } ] }, { catid: '2', catName: 'efg', product: [{ id: 3, qty: 0, }, { id: 4, qty: 1, } ] } ] const quantity = (input) => input.reduce((p, { product }) => p + product.reduce((p, { qty }) => p + qty, 0), 0) console.log(quantity(xyz)) // 10