如何对对象数组进行分组并转换重复项

Question

大家好，我有这个数据结构，我需要对其进行分组，如果有任何重复项可以将这两个对象转换为一行。.

数据结构

var shipTo = [
  { addressLine1: "address 1", name: "Jeff" },
  { addressLine1: "address 2", name: "Taylor" },
  { addressLine1: "address 1", name: "Megan" },
  { addressLine1: "address 3", name: "Madison" },
];

分组函数

function groupArrayOfObjects(list, key) {
  return list.reduce(function (rv, x) {
    (rv[x[key]] = rv[x[key]] || []).push(x);
    return rv;
  }, {});
}

我有groupedBy 地址 attrube 通过上面这个函数的地址

const groupedAddress = groupArrayOfObjects(shipTo, "addressLine1");

我的新数据结构是

我的最终结果希望是这样的：

货件 1 和 1 的送货地址3 是“地址 1”

货件 2 的送货地址是“地址 2”

Answer 1

reduce 可以将当前数组元素的索引作为第三个参数。然后你可以将它传递给你的累加器，并在最终的数组中可以用它做你想做的事情

var shipTo = [
  { addressLine1: "address 1", name: "Jeff" },
  { addressLine1: "address 2", name: "Taylor" },
  { addressLine1: "address 1", name: "Megan" },
  { addressLine1: "address 3", name: "Madison" },
];

function groupArrayOfObjects(list, key) {
  return list.reduce(function (rv, x, idx) {
    (rv[x[key]] = rv[x[key]] || []).push({...x, index:idx+1});
    return rv;
  }, {});
}

const groupedAddress = groupArrayOfObjects(shipTo, "addressLine1");
console.log(groupedAddress)


//for completeness
Object.values(groupedAddress).forEach((address) => {
    let addressName = address[0].addressLine1
  let joinedIndices = address.map(({index}) => index).join(" & ")
  console.log(`Shipping Address for Shipment ${joinedIndices} is "${addressName}"`)
})