映射对象键：值对到JSON的对象数组的数组

Question

I'm trying to convert the following array into something JSON can understand and be able to append the same key/value pair to each array of objects, but I'm getting stuck on how to go about it.

Given the following array of objects:

{
  "array": [
    {
      "Type": "Current",
      "Item1": "3",
      "Item2": "23",
      "Item3": "90",
      "Item4": null,
      "Year": "2019",
      "Amount": "100"
    },
    {
      "Type": "Current",
      "Item1": "3",
      "Item2": "23",
      "Item3": "90",
      "Item4": null,
      "Year": "2020",
      "Amount": "200"
    },
    {
      "Type": "Current",
      "Item1": "3",
      "Item2": "23",
      "Item3": "90",
      "Item4": null,
      "Year": "2021",
      "Amount": "300"
    },
    {
      "Type": "Change",
      "Item1": null,
      "Item2": null,
      "Item3": null,
      "Item4": null,
      "Year": "2019"
    },
    {
      "Type": "Change",
      "Item1": null,
      "Item2": null,
      "Item3": null,
      "Item4": null,
      "Year": "2020",
      "Amount": ""
    },
    {
      "Type": "Change",
      "Item1": null,
      "Item2": null,
      "Item3": null,
      "Item4": null,
      "Year": "2021",
      "Amount": ""
    }
  ]
}

I need to add the following to each array:

{Title : "title", id : "idNum"}

So that it reads like:

{
  "Title": "title",
  "ID": "idNum",
  "Type": "Current",
  "Item1": "3",
  "Item2": "23",
  "Item3": "90",
  "Item4": null,
  "Year": "2019",
  "Amount": "100"
},
{
  "Title": "title",
  "ID": "idNum",
  "Type": "Current",
  "Item1": "3",
  "Item2": "23",
  "Item3": "90",
  "Item4": null,
  "Year": "2020",
  "Amount": "200"
},

etc.

I'm not even sure if this is actually an array of object arrays, as I'm admittedly guessing a bit on the terminology. Eventually, I need this to be able to be processed as a JSON object for submitting to a SharePoint list using AJAX.

Would I need to loop through each array within the array and then add the object key/value pairs?

Answer 1

You can use Array.map and spread and not mutate the original array:

 const data = { "array": [ { "Type": "Current", "Item1": "3", "Item2": "23", "Item3": "90", "Item4": null, "Year": "2019", "Amount": "100" }, { "Type": "Current", "Item1": "3", "Item2": "23", "Item3": "90", "Item4": null, "Year": "2020", "Amount": "200" }, { "Type": "Current", "Item1": "3", "Item2": "23", "Item3": "90", "Item4": null, "Year": "2021", "Amount": "300" }, { "Type": "Change", "Item1": null, "Item2": null, "Item3": null, "Item4": null, "Year": "2019" }, { "Type": "Change", "Item1": null, "Item2": null, "Item3": null, "Item4": null, "Year": "2020", "Amount": "" }, { "Type": "Change", "Item1": null, "Item2": null, "Item3": null, "Item4": null, "Year": "2021", "Amount": "" } ] } result = data.array.map(x => ({ Title: 'Title', ID: 'idNum', ...x})) console.log(result)