Access Dictionary value by key name in ASP.Net using C#

That was my solution.  

In the DateRange.ascx

<%   
    DateTime fromDate = MonatSession.HistoryFromDate;
    DateTime toDate = MonatSession.HistoryToDate;
    string dateTimeFormat = "{0:" + MonatSession.CurrentCustomer.Preferences["Date Format"].ToString() + " H:mm:ss}";
    string dateFormat = MonatSession.CurrentCustomer.Preferences["Date Format"].ToString().ToUpper();


    // Date and Time Format for OV Preference
    //string[] prefArray = MonatSession.CurrentCustomer.Preferences.Values.ToArray();
    //string prefDate = prefArray[0].ToLower();
    //string prefTime = prefArray[1];

    string prefDate = MonatSession.CurrentCustomer.Preferences["Date Format"].ToLower();
    string prefTime = MonatSession.CurrentCustomer.Preferences["Time Format"];

    if (prefTime.Contains("tt"))
        prefTime = prefTime.Replace("tt", "A");
    if (prefTime.Contains("mm"))
        prefTime = prefTime.Replace("mm", "ii");
%>

in the javaScript datePicker:

<script type="text/javascript">

    var popLocation = '<%=Request.Browser.IsMobileDevice ? "bottom" : "center"%>';
    $(document).ready(function () {

        var prefDate = '<%= prefDate %>';
        //var dFormat = prefDate.replace("yyyy", "yy");
        var dFormat = prefDate.replace("yyyy", "yyyy");
        var tFormat = '<%= prefTime %>';

        //New dates pulled from values passed at top of file
        let from = new Date("<%=fromDate%>");
        let to = new Date("<%=toDate%>");

        $('#datePickMobi').mobiscroll().datepicker({
            theme: 'ios',
            controls: ['calendar', 'time'],
            select: 'range',
            display: popLocation,
            defaultSelection: [from, to],
            dateFormat: dFormat.toUpperCase(),
            //timeFormat: tFormat,
            startInput: '#Mobi_startDate',
            endInput: '#Mobi_endDate',
            onChange: function (event, inst) {
                var Dates = inst.getVal();
                var startDate = Dates[0];
                var endDate = Dates[1];
                setSessionDates(startDate, endDate);
                //$('#Mobi_startDate').val(moment(inst._tempStartText).format('<%=dateFormat%>'));
               //$('#Mobi_endDate').val(moment(inst._tempEndText).format('<%=dateFormat%>'));
            }
        });
    });

Thanks.