public void build_excel()
        {
            IPropertyContainer[] rows =
            {
                new MutablePropertyContainer()
                .WithValue(Sheet1Meta.Name, "Alex")
                .WithValue(Sheet1Meta.Age, 42)
                .WithValue(Sheet1Meta.Date, DateTime.Today.ToLocalDateTime().Date),
                new MutablePropertyContainer()
                .WithValue(Sheet1Meta.Name, "Helen")
                .WithValue(Sheet1Meta.Age,                                     17),
            };

            var documentMetadata = new ExcelDocumentMetadata()
                                   .WithValue(ExcelMetadata.DataType, CellValues.SharedString)
                                   .WithValue(ExcelMetadata.FreezeTopRow, true)
                                   .WithValue(ExcelMetadata.ColumnWidth, 14)
                                   as ExcelDocumentMetadata;

            var transposed = new ExcelSheetMetadata()
                             .WithValue(ExcelMetadata.Transpose, true)
                             as ExcelSheetMetadata;

            ExcelReportBuilder
            .Create("build_excel.xlsx", documentMetadata)
            .AddReportSheet(new Sheet1Report("Sheet1"), rows)
            .AddReportSheet(new Sheet1Report("Sheet2").SetMetadata(transposed), rows)
            .SaveAndClose();
        }
        public void build_excel_with_nulls()
        {
            IPropertyContainer[] rows =
            {
                new MutablePropertyContainer(),
            };

            var documentMetadata = new ExcelDocumentMetadata()
                                   .WithValue(ExcelMetadata.DataType, CellValues.SharedString)
                                   .WithValue(ExcelMetadata.FreezeTopRow, true)
                                   .WithValue(ExcelMetadata.ColumnWidth, 14);

            ExcelReportBuilder
            .Create("build_excel.xlsx", documentMetadata)
            .AddReportSheet(new Sheet1Report("Sheet1"), rows)
            .SaveAndClose();
        }