在 JS 中的数组中加法

Question

我必须在javascript中做一个添加，使用如下数组：[{name: "toto",note: 2},{name: "titi",note: 4},{name: "toto",note: 5}]我想得到2 + 4 + 5 = 11（平均值更好，为3.6666）。我尝试了.reduce，但我做不到。有什么帮助吗？谢谢

Answer 1

方式.reduce()

let data = [

{name: "toto",note: 2},

{name: "titi",note: 4},

{name: "toto",note: 5}

]

let result = data.reduce((a,v) => v.note + a, 0);

console.log(result);

Answer 2

相当短的代码

    const data = [

        { name: "toto", note: 2 },

        { name: "titi", note: 4 },

        { name: "toto", note: 5 }

    ];

    const average = data.reduce((a, { note }) => {

        return a + note;

    }, 0) / data.length;

    console.log(average);

Answer 3

你也可以使用一个循环（在我的测试中，它比 reduce（）快50%）来构建总和：

let a = [

{name: "toto",note: 2},

{name: "titi",note: 4},

{name: "toto",note: 5}

];

let sum = 0;

for(var i=0; i< a.length; i++){

    sum += a[i].note;

}

// sum = 11

如果你想要平均值：

let avg = sum / a.length;

// avg = 3.6666~

Answer 4

你可以试试：

const arr = [

  {name: "toto",note: 2},

  {name: "titi",note: 4},

  {name: "toto",note: 5}

]

const result = arr.reduce((acc, { note }) => acc += note,0)

console.log((result/arr.length).toFixed(4))