JSFiddle - React, Tailwind, and code Playground

by timvdh

JavaScript

var arr = [];
var index = {};

var o1 = {id: 0, key: "A", data: "X"};
var o2 = {id: 1, key: "B", data: "Y"};

arr.push(o1);
arr.push(o2);
index[o1.key] = o1;
index[o2.key] = o2;

var lookupKey = "B";

// modify object
arr[1].data = "Z";

// get data for key "B" - alerts "Z"
alert(index[lookupKey].data);