As HTML 5 has become more popular among web developers recently, another popular web client framework jQuery is also proving to be up to date in providing its support for HTML 5. In this article I will be discussing the data attribute features of HTML 5 and the support offered by jQuery with a few examples.
HTML 5 Data Attributes
HTML 5 provides a good feature called the custom data attributes where you can store the data at the page level and can access it from the client scripts as and when it is needed. Developers who have done a few workarounds in the past for storing the data will be relieved. All you need to do is add the prefix “data-“ to the custom attribute of the HTML control and get it working. Below is a sample HTML code.
<body>
<div data-site="www.codeguru.com" data-category="Technology">Hi, Welcome to HTML 5 data attributes!</div>
<div data-name="Dave" data-age=23 data-dept="Clerical">Hi Dave!</div>
</body>
</html>
The beautiful thing with the custom data attributes is that it is backward compatible and it does not have browser dependency issues.
.data() in jQuery API
Nowadays most of the web applications use jQuery, so for developers to make use of HTML 5 features like custom data attributes, it is important that they also have adequate support from jQuery to accomplish the tasks effectively. jQuery provides full support for the HTML 5 custom data attributes. The .data() method of jQuery API is used to play with the HTML 5 custom data attributes.
In the following sections let us see the basic operations set, get and remove what you can do with JQuery on HTML custom data attributes.
Setting Data Attribute Values Using jQuery
In this section let us see about setting the data attribute value through jQuery.
<!DOCTYPE html>
<html>
<head>
<title>Untitled Page</title>
<script type="text/javascript">
$("#btnSet").click(function (e) {
$("#divEmployee").data("name", "Dave");
$("#divEmployee").data("age", "23");
$("#divEmployee").data("dept", "Clerical");
});
</script>
</head>
<body>
<div id="divEmployee">Hi Dave!</div>
<input type="button" id="btnSet" value="Set Value"/>
</body>
</html>
You can also pass a data object as a whole to the .data function, as shown in the below example, instead of writing repeated code.
<script type="text/javascript">
$("#btnSet").click(function (e) {
$("#divEmployee").data({ "name": "Dave", "age": 23, "dept": "Clerical" });
});
</script>
The same also can be written as:
<script type="text/javascript">
$("#btnSet").click(function (e) {
$("#divEmployee").data("name", "age", "dept").data("Dave", 23, "Clerical");
});
</script>
Fetching Data Attribute Values Using jQuery
In this section we will see how to fetch the data attribute values from the HTML controls using jQuery. Below is the sample.
<!DOCTYPE html>
<html>
<head>
<title>Untitled Page</title>
<script type="text/javascript">
$("#btnSet").click(function (e) {
var name = $("#divEmployee").data("name")
var age = $("#divEmployee").data("age")
var dept = $("#divEmployee").data("dept")
});
</script>
</head>
<body>
<div data-name="Dave" data-age="23" data-dept="Clerical" id="divEmployee">Hi Dave!</div>
<input type="button" id="btnGet" value="Get Value"/>
</body>
</html>
If the data attribute of the HTML control has the value as a data object itself then the individual property values can be accessed as shown below.
<!DOCTYPE html>
<html>
<head>
<title>Untitled Page</title>
<script type="text/javascript">
$("#btnSet").click(function (e) {
var name = $("#divEmployee").data("employee").name;
var age = $("#divEmployee").data("employee").age;
var dept = $("#divEmployee").data("employee").dept;
});
</script>
</head>
<body>
<div data-employee='{"name":"Dave", "age": 23, "dept":"Clerical"}' id="divEmployee">Hi Dave!</div>
<input type="button" id="btnGet" value="Get Value"/>
</body>
</html>
Removing Data Attributes Using jQuery
Finally in this section let us see how to remove a data attribute from an HTML control using jQuery API.
<!DOCTYPE html>
<html>
<head>
<title>Untitled Page</title>
<script type="text/javascript">
$("#btnSet").click(function (e) {
$("#divEmployee").removeData("employee");
});
</script>
</head>
<body>
<div data-employee='{"name":"Dave", "age": 23, "dept":"Clerical"}' id="divEmployee">Hi Dave!</div>
<input type="button" id="btnGet" value="Get Value"/>
</body>
</html>
I hope this article was helpful in understanding the different operations that you can perform on data attributes using jQuery.
Happy reading!