Beginning ASP.NET 4.5 in CSharp and VB Opsylum

402 x CHAPTER 11 JQUERY
In the following table you see a list of jQuery’s basic filters. Remember, you can try out each example
by replacing the //Examples go here line with the code examples given. Then save the page
and load it in your browser to see the code at work.
FILTER
:first
:last
:odd
:even
:eq(index)
:lt(index)
:gt(index)
PURPOSE
Enables you to select the first or last item in a matched set. The following example
changes the background color of the first or last row of the table to red:
$('#DemoTable tr:first').css('background-color', 'red');
$('#DemoTable tr:last').css('background-color', 'red');
First, the table is found using #DemoTable. Then all its rows are found using tr.
Finally, the first or last row is found using the :first and :last filters.
Enables you to select the odd or even items in a matched set. The following
example changes the background color of the odd rows of the table to red.
Because the numbering is zero-based, you actually see the second and fourth
rows change color (because they have an index of 1 and 3, respectively).
$('#DemoTable tr:odd').css('background-color', 'red');
Matches elements by their index. :eq (equals) returns a single element by its
index, and :lt (less than) and :gt (greater than) return items smaller or greater
than the given index, respectively. Examples:
// Changes the color in the first row (with an index of 0)
$('#DemoTable tr:eq(0)').css('color', 'green');
// Changes only the last two rows. The first three
// with an index of 0, 1 and 2 respectively, are skipped.
$('#DemoTable tr:gt(2)').css('color', 'green');
// Changes the text color of the first two rows to green.
$('#DemoTable tr:lt(2)').css('color', 'green');
:header
Finds all headers (from h1 to h6) in the page. Example:
$(':header').css('color', 'green');
For a complete list of all basic filters, check out the jQuery documentation at http://api.jquery
.com/category/selectors/.
Advanced Filters
Besides the basic filters you just saw, jQuery supports a lot more filters that enable you to get items
based on the text they contain, whether or not they are visible, and also on any attributes they may
have. Additionally, you can find filters to get at form elements (like buttons, check boxes, radio buttons,
and so on) and a number of selectors that enable you to select children, parents, siblings, and
descendants. The following table lists the ones you’ll use most. The online jQuery documentation
gives you access to the complete list, with full working examples showing how they work.