如何访问自定义销毁绑定中的变量

所以我使用这个日期选择器库。http://eonasdan.github.io/bootstrap-datetimepicker/Installing/淘汰赛

是否有一种方法可以让我从处理程序中获取值并将其保存在视图模型中?我想在视图模型的处理程序外部公开var picker = $(element).data('DateTimePicker');的值。这可能吗?

/*globals Hilary*/
Hilary.scope('learn').register({
    name: 'DatetimeVM',
    dependencies: ['ko', 'jQuery', 'moment', 'OptionSelectVM'],
    factory: function (ko, $, moment, OptionSelectVM) {
        'use strict';
        return function (date) {
            var self = {
                date: {
                    type: ko.observable(),
                    start: ko.observable(),
                    end: ko.observable()
                }
            };
            if(!ko.bindingHandlers.dateTimePicker) {
                ko.bindingHandlers.dateTimePicker = {
                    init: function (element, valueAccessor, allBindingsAccessor) {
                        //initialize datepicker with some optional options
                        var viewOptions = allBindingsAccessor().dateTimePickerOptions || {},
                            options;
                        options = $.extend({
                            inline: true,
                            debug: true
                        }, viewOptions);
                        $(element).datetimepicker(options);
                        //when a user changes the date, update the view model
                        ko.utils.registerEventHandler(element, 'dp.change', function (event) {
                            var value = valueAccessor();
                            if (ko.isObservable(value)) {
                                if (event.date !== null && !(event.date instanceof Date)) {
                                    value(event.date.toDate());
                                } else {
                                    value(event.date);
                                }
                            }
                        });
                        ko.utils.domNodeDisposal.addDisposeCallback(element, function () {
                            var picker = $(element).data('DateTimePicker');
                            if (picker) {
                                picker.destroy();
                            }
                        });
                    },
                    update: function (element, valueAccessor) {
                        var picker = $(element).data('DateTimePicker');
                        //when the view model is updated, update the widget
                        if (picker) {
                            var koDate = ko.utils.unwrapObservable(valueAccessor());
                            //in case return from server datetime i am get in this form for example /Date(93989393)/ then fomat this
                            // koDate = (typeof (koDate) !== 'object') ? new Date(parseFloat(koDate.replace(/[^0-9]/g, ''))) : koDate
                            picker.date(koDate);
                        }
                    }
                };
            }
            return self;
        };
    }
});