const items = [{id: 1}, {id: 2}, {id: 3}];Add new item at the start (unshift)
let item = {id: 0};
items.unshift(item);Add new item at the end (push)
let item = {id: 5};
items.push(item);Add new item in the middle (splice)
let item = {id: 4};
// Array.splice({index where to start}, {how many items to remove}, {items to add});
items.splice(4, 0, item);Find an item in an array by its values (find)
let result = items.find(x => x.id === 2);
Get multiple items from an array that match a condition (filter)
let result = items.filter(x => x.id % 2);
Transform items of an array (map)
let result = items.map(x => x.id);
Add a property to every item of an array (forEach)
items.forEach((x, i) => x['index']= i + 1);
Sort an array by a property (sort)
items.sort((a, b) => a.id < b.id);
Check each item for a specific condition (every, some)
let result = items.some(x => x.id === 2); // true
let result = items.every(x => x.id === 2); // false