嵌套对象减少分组和求和 - javascript

如何解决嵌套对象减少分组和求和 - javascript

我有一个带有数据的 json 对象，我需要按名称对这些对象进行分组，按名称对权重求和，然后对成绩求和。我已经尝试了2天了。它应该看起来像 {name,weightTotal,grade{grade1total:,grade2total,grade2total}}...我查看了大约 30 个堆栈 qs 并尝试减少和 foreach groupby 并且我不明白其中任何一个，我是第三名一年级学生做我的第一个实习。需要它在前端进展以将这些显示为表格。顺便说一下，这些来自休息端点。

数据

"data": [
    {
      name: "france Naicin",avgTotalWeight: 16,grade: {
        grade1: 16,grade2: 0,grade3: 0,},{
      name: "pacific gigas",{
      name: "france Naicin",avgTotalWeight: 13,grade: {
        grade1: 13,avgTotalWeight: 14,grade: {
        grade1: 14,avgTotalWeight: 15,grade: {
        grade1: 15,],

我获取这个json的代码：

let a = [];

    for (let i = 0; i <= data.length; i++) {
      if (!data[i]) {
        continue;
      }

      const {avgTotalWeight} = data[i];
      const {name} = data[i].truerun.batch.shellfish;
      const {alias} = data[i].truerun.grade_list;
      const {updatedAt} = data[i];
      const {isExist} = data[i].truerun;

      if (avgTotalWeight !== null) {
        let grade1,grade2,grade3 = 0;

        if (alias === "G1") {
          grade1 = avgTotalWeight;
        } else grade1 = 0;

        if (alias === "G2") {
          grade2 = avgTotalWeight;
        } else grade2 = 0;

        if (alias === "G3") {
          grade3 = avgTotalWeight;
        } else grade3 = 0;

        let b = {
          name: name,avgTotalWeight: avgTotalWeight,//updatedAt: updatedAt,//isExist: isExist,grade: {
            grade1: grade1,grade2: grade2,grade3: grade3,};

        a.push(b);
      }
    }

    return a;

解决方法

您可以使用 reduce

轻松实现此结果

如果某些情况下 grade 键增加，那么您可以添加动态代码，以便它可以与 grade 中的无限键一起使用。直接替换

isExist.grade.grade1 += grade.grade1;
isExist.grade.grade2 += grade.grade2;
isExist.grade.grade3 += grade.grade3;

与

Object.keys(isExist.grade).forEach((key) => {
  isExist.grade[key] += curr.grade[key];
});

const obj = {
  data: [
    {
      name: "france Naicin",avgTotalWeight: 16,grade: {
        grade1: 16,grade2: 0,grade3: 0,},{
      name: "pacific gigas",{
      name: "france Naicin",avgTotalWeight: 13,grade: {
        grade1: 13,avgTotalWeight: 14,grade: {
        grade1: 14,avgTotalWeight: 15,grade: {
        grade1: 15,],};

const result = obj.data.reduce((acc,curr) => {
  const { name,avgTotalWeight,grade } = curr;
  const isExist = acc.find((o) => o.name === name);
  if (isExist) {
    isExist.weightTotal += avgTotalWeight;
    isExist.grade.grade1 += grade.grade1;
    isExist.grade.grade2 += grade.grade2;
    isExist.grade.grade3 += grade.grade3;
  } else {
    acc.push({
      name,weightTotal: avgTotalWeight,grade,});
  }
  return acc;
},[]);

console.log(result);