The copyWithin() method of TypedArray instances shallow copies part of this typed array to another location in the same typed array and returns this typed array without modifying its length. This method has the same algorithm as Array.prototype.copyWithin.
Syntax
copyWithin(target, start)
copyWithin(target, start, end)
Parameters
target- : Zero-based index at which to copy the sequence to, converted to an integer. This corresponds to where the element at
startwill be copied to, and all elements betweenstartandendare copied to succeeding indices.
- : Zero-based index at which to copy the sequence to, converted to an integer. This corresponds to where the element at
start- : Zero-based index at which to start copying elements from, converted to an integer.
end- : Zero-based index at which to end copying elements from, converted to an integer.
copyWithin()copies up to but not includingend.
- : Zero-based index at which to end copying elements from, converted to an integer.
Return value
The modified typed array.
Description
See Array.prototype.copyWithin for more details. This method is not generic and can only be called on typed array instances.
Examples
Using copyWithin()
const buffer = new ArrayBuffer(8);
const uint8 = new Uint8Array(buffer);
uint8.set([1, 2, 3]);
console.log(uint8); // Uint8Array [ 1, 2, 3, 0, 0, 0, 0, 0 ]
uint8.copyWithin(3, 0, 3);
console.log(uint8); // Uint8Array [ 1, 2, 3, 1, 2, 3, 0, 0 ]