Here's what my array looks like
[
{ name: "myname", date: dateObj, value: 2 },
{ name: "othername", date: dateObj, value: 3 },
{ name: "newname", date: dateObj, value: 5 },
]
Dates are native date objects.
What would be the smartest way to get the one object with the oldest date? Is there a better way than sorting the whole array by looping through?
You can use Array.reduce() to iterate the array, and on each iteration pick the object with the oldest date:
const data = [
{ name: "myname", date: new Date(2016, 5, 1), value: 2 },
{ name: "othername", date: new Date(2018, 6, 1), value: 3 },
{ name: "newname", date: new Date(2017, 12, 1), value: 5 },
];
const result = data.reduce((r, o) => o.date < r.date ? o : r);
console.log(result);
Yes. The Array must be pre-sorted. :)
In other words, No. Without iterating the whole Array, there seems no way to find out the Object with oldest date. We need to iterate the Array.
This should do what you want, if we call your array myArray:
myArray.sort((objA, objB) => objA.date.getTime() - objB.date.getTime())[0];
dateA, dateB in .sort() contain object. You should use dateB.date
Is there a better way than sorting the whole array by looping through?. Without iterating through the array, how would you know what's inside it to begin with? It might be that this is the result of some DB query, in which case the best way would be to have the DB sort the returned items.