How do you JSON serialize a set of hidden input values (jQuery can be used)?

Question

I have the following DOM structure..

<input id="WorkAssignmentID_3462" type="hidden" value="3462" name="WorkAssignmentID"/>
<input id="WorkItemID_3462" type="hidden" value="3633" name="WorkItemID"/>
<input id="EmployeeID_3462" type="hidden" value="15" name="EmployeeID"/>
<input id="AssignedBy_3462" type="hidden" value="Jonathan Erickson" name="AssignedBy"/>
<input id="AssignedDate_3462" type="hidden" value="8/1/2009 12:00:00 AM" name="AssignedDate"/>
<input id="ExpirationDate_3462" type="hidden" value="" name="ExpirationDate"/>
<input id="RegisteredDate_3462" type="hidden" value="8/1/2009 12:00:00 AM" name="RegisteredDate"/>

lets just say the jQuery selector to get all of those DOM elements is the following:

$('#assignment');

and what I want to do is create a JSON object from that set:

var WA = {
    WorkAssignmentID: '3462',
    WorkItemID: '3633',
    EmployeeID: '15',
    AssignedBy: 'Jonathan Erickson',
    AssignedDate: '8/1/2009 12:00:00 AM',
    ExpirationDate: '',
    RegisteredDate: '8/1/2009 12:00:00 AM',
};

what would be the easiest way to do that?

I was thinking of doing something like this, but it doesn't work because I don't think that you can dynamically create the property of the JSON object... is it possible to dynamically create the property name?

var WA = {};

$('#assignment').each(function(idx, elem) {
    $.extend(WA, {
                     $(elem).attr('name'): $(elem).val()
                 });
});

Answer 1

What about this, using the bracket notation:

var result = {};

$('input[type=hidden]').each(function() {
    result[this.name] = this.value;
});

Answer 2

Calling $.extend() is overkill, IMO. But you've got the basic approach I'd use

var WA = {};
$('input[type="hidden"]').each( function( idx, elem )
{
  WA[elem.name] = elem.value;
}