DateFormatting.cshtml

@using Quickstart.Web.Extensions
@model Quickstart.Web.Models.Person

@section scripts
{
    <script type="text/javascript" src="/Scripts/moment.min.js"></script>
    <script type="text/javascript" src="/Scripts/knockout.bindings.date.js"></script>
    <script type="text/javascript">
        var viewModel = ko.mapping.fromJS(@Html.Raw(Model.ToJson()));
        ko.applyBindings(viewModel);
    </script>
}

<h2>Date Formatting With Moment.js</h2>

<div>
    <label>Date of Birth:</label>
    <input type="text" data-bind="date: dateOfBirth, format: 'DD MMM YYYY'" />
</div>

knockout.bindings.date.js

ko.bindingHandlers.date = {
    // https://disqus.com/home/discussion/jasonmitchellcom/binding_and_formatting_dates_using_knockout_and_moment_js/#comment-1374417079
    init: function (element, valueAccessor, allBindingsAccessor, viewModel) { 
        ko.utils.registerEventHandler(element, 'change', function () {
        var value = valueAccessor();
        if (element.value !== null && element.value !== undefined && element.value.length > 0) { 
            value(element.value);
        }
        else {
            value('');
        }
        });
    },
    update: function (element, valueAccessor, allBindingsAccessor, viewModel) {
        var value = valueAccessor();
        var allBindings = allBindingsAccessor();
        var valueUnwrapped = ko.utils.unwrapObservable(value);

        // Date formats: http://momentjs.com/docs/#/displaying/format/
        var pattern = allBindings.format || 'DD/MM/YYYY';

        var output = "-";
        if (valueUnwrapped !== null && valueUnwrapped !== undefined && valueUnwrapped.length > 0) {
            output = moment(valueUnwrapped).format(pattern);
        }

        if ($(element).is("input") === true) {
            $(element).val(output);
        } else {
            $(element).text(output);
        }
    }
};