[Export(typeof(IDataExporter))]
    public class ExcelDataExporter : IDataExporter
    {
        public string FormatName { get { return "Excel"; } }

        public void Export(IEnumerable<Feature> dataSource)
        {          
            if (dataSource.Count() == 0)
            {
                MessageBox.Show("No results to export.");
                return;
            }

            var dlg = new SaveFileDialog { Filter = "Excel Document (.xlsx)|*.xlsx", DefaultExt = ".xlsx" };
            if (dlg.ShowDialog() == true)
            {
                var doc = new SpreadsheetDocument();
                doc.ApplicationName = "FDOT.GIS.Framework";
                doc.Creator = "FDOT.GIS.Framework";

                var keys = dataSource.First().FeatureType.Attributes;

                var i = 0;
                foreach (var key in keys)
                {                    
                    doc.Workbook.Sheets[0].Sheet.Rows[0].Cells[i].SetValue(key.Description);
                    i++;
                }


                var j = 1;
                foreach (var feature in dataSource)
                {
                    i = 0;
                    foreach (var key in keys)
                    {
                        var cell = doc.Workbook.Sheets[0].Sheet.Rows[j].Cells[i];

                        if (feature[key] != null && feature[key].GetType() != typeof(string))
                        {
                            Type rowDataType = feature[key].GetType();
                            if (rowDataType == typeof(DateTime))
                            { cell.SetValue((DateTime)feature[key]); }
                            else if (rowDataType == typeof(bool))
                            { cell.SetValue((bool)feature[key]); }

                            decimal rowValue = 0;
                            bool result = Decimal.TryParse(feature[key].ToString(), out rowValue);
                            if (result)
                            { cell.SetValue(rowValue); }
                            else
                            { cell.SetValue((feature[key] ?? "").ToString()); }
                        }
                        else
                        { cell.SetValue((feature[key] ?? "").ToString()); }
                        
                        i++;
                    }
                    j++;
                }

                using (var storage = new ZipStreamProvider(dlg.OpenFile() ))
                {
                    doc.Save(storage);
                }
            }

            LayoutManager.Instance.ShowMessage("Excel export complete.");
        }

        public string IconResourceUri
        {
            get { return "Assets/Images/excel_icon.png"; }
        }

        /// <summary>
        /// Returns true if the command has been initialized.
        /// </summary>
        public bool IsInitialized { get; private set; }

        /// <summary>
        /// Initialize the command with the provided settings.
        /// </summary>
        /// <param name="customSettings"></param>
        public void Initialize(IDictionary<string, string> customSettings)
        {
            if (!IsInitialized)
                OnInitialize(customSettings);

            IsInitialized = true;
        }

        protected virtual void OnInitialize(IDictionary<string, string> customSettings) 
        { }
    }