even selector
Description: Selects even elements, zero-indexed. See also odd.
version added: 1.0jQuery( ":even" )
In particular, note that the 0-based indexing means that, counter-intuitively, :even selects the first element, third element, and so on within the matched set.
Additional Notes:
- Because
:evenis a jQuery extension and not part of the CSS specification, queries using:evencannot take advantage of the performance boost provided by the native DOMquerySelectorAll()method. To achieve the best performance when using:evento select elements, first select the elements using a pure CSS selector, then use.filter(":even"). - Selected elements are in the order of their appearance in the document.
Example:
Finds even table rows, matching the first, third and so on (index 0, 2, 4 etc.).
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>even demo</title>
<style>
table {
background: #eee;
}
</style>
<script src="https://code.jquery.com/jquery-1.10.2.js" rel="external nofollow" ></script>
</head>
<body>
<table border="1">
<tr><td>Row with Index #0</td></tr>
<tr><td>Row with Index #1</td></tr>
<tr><td>Row with Index #2</td></tr>
<tr><td>Row with Index #3</td></tr>
</table>
<script>
$( "tr:even" ).css( "background-color", "#bbf" );
</script>
</body>
</html> 
