计算嵌套 object 数组中的键值

Question

我有一个这样的数组：

[
   {
        "costs": [{
            "value": "80"
        }],
        "id": 4,
        "name": "Subscription Fee",
        "month": "March"
    },
    [
      {
          "costs": [{
            "value": "200"
          }],
          "id": 2,
          "name": "Tution",
          "month": "March"
      },
      {
          "costs": [{
              "value": "10"
          }],
          "id": 11,
          "name": "DEMO"
      }
   ]
]

我需要汇总成本中的所有值。 我怎样才能做到这一点？

Answer 1

 const data = [ {"costs":[{"value":"80"}],"id":4,"name":"Subscription Fee","month":"March"}, [ {"costs":[{"value":"200"}],"id":2,"name":"Tution","month":"March"}, {"costs":[{"value":"10"}],"id":11,"name":"DEMO"} ] ]; // flatten the arrays to get a list of objects // iterate over this list const res = data.flat().reduce((total, { costs = [] }) => { // add the values of this item's costs with total costs.forEach(({ value = 0 }) => total += +value); return total; }, 0); console.log(res);