DOM Traversal Methods - MarkMail

Chapter 5
Description
This handler is a shortcut for .bind('change', handler) in the first variation, and
.trigger('change') in the second.
The change event is sent to an element when its value changes. This event is limited
to fields, boxes, and elements. For
select boxes, the event is fired immediately when the user makes a selection with the
mouse, but for the other element types the event is deferred until the element loses
focus.
For example, consider the HTML:
Option 1
Option 2
Trigger
The event handler can be bound to the text input and the select box:
$('.target').change(function() {
$(this).log('Change event was triggered.');
});
Now when the second option is selected from the dropdown, the message is
displayed. It is also displayed if we change the text in the field and then click away.
If the field loses focus without the contents having changed, though, the event is not
triggered. We can trigger the event manually when the button is clicked:
$('.trigger').click(function() {
$('.target').change();
});
After this code executes, clicks on the trigger button will also display the message.
The message will be displayed twice, because the handler has been bound to the
change event on both of the form elements.
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