hide - Understanding jQuery

There is, indeed, a third way to bind and unbind event handlers. An example can be seen below:
var handler = function()
{
alert(‘The quick brown fox jumps over the lazy dog.’);
};
$(‘#orange’).bind(‘click’, handler);
$(‘#orange’).unbind(‘click’, handler);
By naming our event handler (so that it is no longer a function closure) and separating it from
the bind and unbind functions, we are able to explicitly tell jQuery to work with the original
location in memory of the object that we created.
This means that you will be binding and unbinding only click events assigned by your script.
Imagine if some other script (not developed by you) assigns a click event handler to the
HTML element with ID “orange” and that we unbind it by accident using our code. We would
interrupt the flow of that other script.
But Javascript code can be very sensitive to syntax being used. There is one more precaution
you should be aware of when binding and unbinding your event handlers. Consider the code
below:
$(‘#orange’).bind(‘click’, function()
{
alert(‘The quick brown fox jumps over the lazy dog.’);
});
// This will NOT unbind the event handler attached above
$(‘#orange’).unbind(‘click’, function() {
alert(‘The quick brown fox jumps over the lazy dog.’);
});
The unbind event in the example above will not actually unbind the event handler attached
with the bind function right above it. Why not? Because the first function created a function
closure located at an arbitrary address in memory.
The second function did the same thing. Essentially, we are telling Javascript to unbind an
event handler we have just created, yet, instead of giving the unbind function the handle to
that event, in the second example we are trying to unbind a brand new function we are creating
at the same time.
Nameless functions that we have specified “on the fly” will always be stored at a new, unique
address in memory even if their contents are exactly the same.
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