Binding event handlers using jquery on method

The syntax for using on() and off() methods is very similar to using bind() and unbind() methods. The following example is the same example we worked with in Part 33. Instead of using bind() and unbind() we are using on() and off() methods.

<html>
<head>
    <title></title>
    <style>
        .ButtonStyle {
            background-color: red;
            cursor: pointer;
            font-weight: bold;
            color: white;
        }
    </style>
    <script src="jquery-1.11.2.js"></script>
    <script type="text/javascript">
        $(document).ready(function () {
            $('#btnClickMe').on('click mouseover mouseout', function (event) {
                if (event.type == 'click') {
                    $('#divResult').html('Button Clicked at ' + 'X = '
                        + event.pageX + ' Y = ' + event.pageY);
                }
                else if (event.type == 'mouseover') {
                    $(this).addClass('ButtonStyle');
                }
                else {
                    $(this).removeClass('ButtonStyle');
                }
            });

            $('#btnEnableMouseOverEffect').click(function () {
                $('#btnClickMe').on('mouseover', function () {
                    $(this).addClass('ButtonStyle');
                });
            });

            $('#btnDisableMouseOverEffect').click(function () {
                $('#btnClickMe').off('mouseover');
            });
        });
    </script>
</head>
<body style="font-family:Arial">
    <input id="btnClickMe" type="button" value="Click Me" />
    <input id="btnEnableMouseOverEffect" type="button"
           value="Enable Mouse Over Effect" />
    <input id="btnDisableMouseOverEffect" type="button"
           value="Disable Mouse Over Effect" />
    <br /><br />
    <div id="divResult"></div>
</body>
</html>

In the example above we are binding a single anonymous function as the event handler for all the 3 events
1. click
2. mouseover
3. mouseout

If you want to bind a different anonymous function, you could do so using the following syntax.
$('#btnClickMe').bind({
    click: function (event) {
        $('#divResult').html('Button clicked at X = '
            + event.pageX + ' Y = ' + event.pageY);
    },
    mouseover: function () {
        $(this).addClass('ButtonStyle');
    },
    mouseout: function () {
        $(this).removeClass('ButtonStyle');
    }
});

jQuery shorthand functions (.click, .mouseover, .mouseout etc.) call on() method behind the scenes.

So far in this video series we have seen 3 different ways of binding event handlers in jQuery
1. Using jQuery shorthand functions (.click, .mouseover, .mouseout etc.)
element.click(function () { ... });

2. With jQuery version < 1.7, bind() method can be used
element.bind('click', function () { ... });

3. With jQuery version 1.7 or higher, on() method can be used. 
element.on('click', function () { ... });

According to jQuery.com, as of jQuery 1.7, the .on() method is the preferred method for attaching event handlers. 

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