Using JavaScript Array copyWithin() Method, you can copy the part of the given array with its own elements. This method copies array elements from one position to another in the given array and overwrites the existing values.
array.copyWithin(target, start, end)- target – The index position to copy the elements to.
- start (optional) – The index position to start copying elements from. If omitted, it will copy from index 0.
- end (optional) – The index position to stop copying elements from (end element not included). If omitted, it will copy until the last index.
Note: It does not change the length of the original array.
JavaScript Array copywithin()
Simple example code.
<!DOCTYPE html>
<html>
<body>
<script>
let words = ["Apple", "Ball", "Cat", "Dog"];
// copies element from index 0 to index 3
words.copyWithin(3, 0);
console.log(words);
</script>
</body>
</html>Output:
More examples
const arr = ['a', 'b', 'c', 'd', 'e'];
// copy to index 0 the element at index 3
console.log(arr.copyWithin(0, 3, 4)); //["d", "b", "c", "d", "e"]
// copy to index 1 all elements from index 3 to the end
console.log(arr.copyWithin(1, 3)); // ["d", "d", "e", "d", "e"]Do comment if you have any doubts or suggestions on this JS Array method tutorial.
Note: The All JS Examples codes are tested on the Firefox browser and the Chrome browser.
OS: Windows 10
Code: HTML 5 Version