Question

Jquery in Action has the following code:

$('#someField').val($.trim($('#someField').val()));

When I rewrite as follows though, the code does not work.

$('#someField').val($.trim($(this));

Can anyone help me understand why this does not work?

Answer 1

Two reasons:

• trim takes a string, not a jQuery object. You’d need $(this).val() at least.

• The selector is not encapsulating a function, so this actually doesn’t get set to the object you selected. this is whatever it was anyway.

The best solution is this:

var $obj = $('#someField');
$obj.val($.trim($obj.val()); // trim object's value