Find the highest number in a json object with javascript and a corresponding index or another value-CodePudding

This javascript find the highest number but i want the corresponding id and index too, or the corresponding id. This is not a duplicate question since i'm looking for the id or the index and not just finding the highest number.

const shots = [{
    id: 1,
    amount: 2
  },
  {
    id: 2,
    amount: 4
  },
  {
    id: 3,
    amount: 52
  },
  {
    id: 4,
    amount: 36
  },
  {
    id: 5,
    amount: 13
  },
  {
    id: 6,
    amount: 33
  }
];

var highest = shots.reduce((acc, shot) => acc = acc > shot.amount ? acc : shot.amount, 0);

var highest = Math.max.apply(Math, shots.map(function(o) { return o.amount; }))

In this example the highest number is 52 then it mean that the corresponding index is 2. how to get this index value?

Finally, i need to get the corresponding id.

In real life, i should find the highest bitrate to get the corresponding highest quality video url.

CodePudding user response：

Once you have the highest amount, you can .findIndex to get the object with that amount.

const shots=[{id:1,amount:2},{id:2,amount:4},{id:3,amount:52},{id:4,amount:36},{id:5,amount:13},{id:6,amount:33}];

const highest = Math.max(...shots.map(o => o.amount));
const index = shots.findIndex(o => o.amount === highest);
console.log(index, shots[index].id);

Or if you wanted to do it with just a single iteration

const shots=[{id:1,amount:2},{id:2,amount:4},{id:3,amount:52},{id:4,amount:36},{id:5,amount:13},{id:6,amount:33}];

let index = 0;
let best = -Infinity;
shots.forEach((shot, i) => {
  if (shot.amount > best) {
    best = shot.amount;
    index = i;
  }
});
console.log(index, shots[index].id);

If you only want the index to get to the ID, it's a bit easier.

const shots=[{id:1,amount:2},{id:2,amount:4},{id:3,amount:52},{id:4,amount:36},{id:5,amount:13},{id:6,amount:33}];

const best = shots.reduce((a, b) => a.amount > b.amount ? a : b);
console.log(best);