How to Remove a Specific Element from a JavaScript Array?

#javascript #webdev #programming #beginners

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Removing an item from an array is a common operation we do in JavaScript programs.

In this article, we’ll look at how to remove a specific element from a JavaScript array.

We can use the array’s splice method to remove an array item with the given index.

For instance, we can write:

const array = [1, 2, 3];
console.log(array);
const index = array.indexOf(2);
if (index > -1) {
  array.splice(index, 1);
}

console.log(array);

We have an array that we want to remove an item from.

We use the indexOf method to find the first index of the given item in the array.

If it returns anything other than -1, then the item is in the array.

And so if index isn’t -1, we call splice with the index and 1 to remove an item with the given index.

This works well with one entry and if we’re looking for a primitive value.

We can also use the filter method to return the array without the given entry.

For instance, we can write:

const value = 3
let arr = [1, 2, 3, 4, 5]
arr = arr.filter(item => item !== value)
console.log(arr)

We look for value in arr and remove it by calling filter with a callback that returns item !== value .

This will keep anything in arr that has value other than value .

This will remove all entries with the given value so it’s more versatile than using indexOf and splice .

It also works with objects, which makes it more versatile.

indexOf doesn’t work with objects since we can’t specify the condition to look with a callback as we do with filter .

We can remove items with the given condition easily from JavaScript arrays.

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