/*
Example of inline event handlers:
<input type="text" name="date" onchange="validateDate()" />

This is bad.
The purpose of markup is to describe a document's structure, not its programmatic behavior. And what if we need to set handlers for several events on a single element?
*/

// The unobtrusive solution:

<input type="text" name="date" id="date" />

/*
A script that runs when page is loaded into the browser, looks for relevant element(s) and set them up accordingly: (using jquery)
*/

var message = "mouse entered or left.";

// passing the variable in by value through eventData:
$('#date').bind('mouseenter mouseleave', {msg: message}, function(event) {
  alert(event.data.msg);
});

// The unobtrusive solution:

<input type="text" name="date" id="date" />

/*
A script that runs when page is loaded into the browser, looks for relevant element(s) and set them up accordingly: (using jquery)
*/

var message = "mouse entered or left.";

// passing the variable in by value through eventData:
$('#date').bind('mouseenter mouseleave', {msg: message}, function(event) {
  alert(event.data.msg);
});

http://api.jquery.com/bind

unobtrusive multiple event handlers on single element using jQuery

javascript, event, jquery

JavaScript