Find element in array and move it to the first position
1 min read
Surely there are several way to do it, this is just one of them. Let me know if you know a better way to do it 💪🏻
To find an element into an array and move to be the first, you have to:
- get the index of the founded item using
findIndex()
📚 The
findIndex()
method returns the index of the first element in the array that satisfies the provided testing function.
const arr = [1, 2, 3, '🐱', 4, 5, 6, 7, 8, 9 , 10]
const itemToFind = '🐱'
const foundIdx = arr.findIndex(el => el == itemToFind) // -> foundIdx = 3
- remove the item in that specific position using
splice()
📚 The
splice()
method changes the contents of an array by removing or replacing existing elements and/or adding new elements in place.
arr.splice(foundIdx, 1)
// splice(start[, deleteCount[, item1[, item2[, ...]]]])
// start = foundIdx
// deleteCount = 1 = number of elements in the array to remove from start
- add the item to the 1st position using
unshift()
📚 The
unshift()
method adds one or more elements to the beginning of an array and returns the new length of the array.
arr.unshift(itemToFind)
Output
console.log(arr)
// (11) ["🐱", 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
To sum up:
const arr = [1, 2, 3, '🐱', 4, 5, 6, 7, 8, 9 , 10]
const itemToFind = '🐱'
const foundIdx = arr.findIndex(el => el == itemToFind)
arr.splice(foundIdx, 1)
arr.unshift(itemToFind)
📚 More info