javascript - 用map方法求总数？

Question

这个问题已经有答案了:

How to find the sum of an array of numbers (60 个回答)

已关闭 5 年前。

假设我有一些数据。

const cart = [
[{name: "Jose", total: 5}],
[{name: "Rich", total: 10}]
]

如何使用 map 或 forEach 合计这些总数？

Answer 1

How do I total up those totals using map or forEach?

The function Array.map() is to create new arrays applying a specific handler to each element. On the other hand, the function Array.forEach() could be a good approach to loop and sum the values.

最好的方法是使用函数reduce。

假设样本总是有一个只有一个索引的数组。

const cart = [[{name: "Jose", total: 5}],[{name: "Rich", total: 10}]],
      total = cart.reduce((a, [{total} = [obj]]) => a + total, 0);
      
console.log(total);