The copyWithin()
method copies the sequence of array elements within the array to the position starting at target
. The copy is taken from the index positions of the second and third arguments start
and end
. The end
argument is optional and defaults to the length of the array. This method has the same algorithm as Array.prototype.copyWithin
. TypedArray is one of the typed array types here.
Syntax
typedarray.copyWithin(target, start[, end = this.length])
Parameters
target
- Target start index position where to copy the elements to.
start
- Source start index position where to start copying elements from.
end Optional
- Optional. Source end index position where to end copying elements from.
Return value
The modified array.
Description
See Array.prototype.copyWithin
for more details.
This method replaces the experimental TypedArray.prototype.move()
.
Examples
var buffer = new ArrayBuffer(8); var 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 ]
Specifications
Specification | Status | Comment |
---|---|---|
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'TypedArray.prototype.copyWithin' in that specification. |
Standard | Initial definition. |
ECMAScript 2017 Draft (ECMA-262) The definition of 'TypedArray.prototype.copyWithin' in that specification. |
Draft |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | 45.0 | 34 (34) | No support |
36.0 |
No support |
Feature | Android | Chrome for Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|
Basic support | No support | No support | 34.0 (34) | No support | No support | No support |