Converting JavaScript Object With Numeric Keys into Array

Converting JavaScript object with numeric keys into array

It's actually very straight forward with jQuery's $.map

var arr = $.map(obj, function(el) { return el });

FIDDLE

and almost as easy without jQuery as well, converting the keys to an array and then mapping back the values with Array.map

var arr = Object.keys(obj).map(function(k) { return obj[k] });

FIDDLE

That's assuming it's already parsed as a javascript object, and isn't actually JSON, which is a string format, in that case a run through JSON.parse would be necessary as well.

In ES2015 there's Object.values to the rescue, which makes this a breeze

var arr = Object.values(obj);

How to convert an Object {} to an Array [] of key-value pairs in JavaScript

You can use Object.keys() and map() to do this

var obj = {"1":5,"2":7,"3":0,"4":0,"5":0,"6":0,"7":0,"8":0,"9":0,"10":0,"11":0,"12":0}
var result = Object.keys(obj).map((key) => [Number(key), obj[key]]);

console.log(result);

Prevent node.js from converting a nested object with numeric keys into array

Try adding the contentType header and using JSON.stringify to serialize the object before passing to $.ajax:

const express = require("express");
const app = express();

const html = `<!DOCTYPE html>
<head>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.6.0/jquery.min.js">
</script>
</head>
<body>
<script>
$.ajax({
  url: "/cctool/report",
  method: "PUT",
  contentType: "application/json",
  data: JSON.stringify({
    new: {
      10: "Test",
      20: "Hello",
    }
  }),
  success: data => console.log(data),
});
</script></body></html>`;

app
  .use(express.json())
  .get("/", (req, res) => res.send(html))
  .put("/cctool/report", (req, res) => {
    console.log(req.body);
    res.json(req.body);
  })
  .listen(3000);

See jQuery posting JSON.

Is there a way to pass keys into a JavaScript array where a a string might match multiple values of an object?

Use filter instead of find and map to remove the values.

const obj = { quay: "foo", key1: "blargh", yaya: "foo", idnet: "blat", blah: "foo", hahas: "blargh" }

const str = 'foo';

const keys = Object.entries(obj).filter(([, val]) => val === str).map(([key]) => key);
console.log(keys);

Converting JavaScript Object With Numeric Keys into Array