JavaScript Array method: copyWithin()
[this page | pdf | back links]
The copyWithin() method (when applied to a
JavaScript
array) copies
elements to and from specified positions.
It
has the following syntax with the following parameters. It returns an array
(the changed array).
array.copyWithin(target, start, end)
|
Parameter
|
Required / Optional
|
Description
|
|
target
|
Required
|
The index position
where elements start to be copied to
|
|
start
|
Optional
|
The index position
where elements start to be copied from (default is zero)
|
|
end
|
Optional
|
The index position
where elements stop being copied from (default is array.length
|
EXAMPLE:
HTML USED IN THIS EXAMPLE:
<!DOCTYPE html>
<html> <!-- Copyright (c) Nematrian Limited 2018 -->
<head>
<style>
table,th,tr,td {border: 1px solid black; border-collapse: collapse;}
</style>
</head>
<body>
<table>
<tr>
<th>Example</th>
<th>Resulting value of <code>x</code></th>
</tr>
<tr>
<td><code id="Example"></code></td>
<td><code id="Result"></code></td>
</tr>
</table>
<script>
var h = ["a","b","c","d"];
document.getElementById("Example").innerHTML =
'var h = ["a","b","c","d"];' + '<br>' +
'var x = h.copyWithin(2,0);';
document.getElementById("Result").innerHTML
= h.copyWithin(2,0);
</script>
</body>
</html>
|
FUNCTION THAT MAY ASSIST IN TESTING WHETHER FEATURE IS SUPPORTED:
function isSupportedJavaScriptMethodArrayCopyWithin() {
var h = [1, 2, 3]; return !!h.copyWithin;
} |
NAVIGATION LINKS
Contents | Prev | Next | JavaScript Arrays