Unplanned
Last Updated: 30 Jul 2026 06:08 by Steve

Importing an XLSX workbook can crash with System.ArgumentNullException: Value cannot be null. Parameter name: key during Workbook.ResumeCalculationMapRegistration().

Root cause:
The XLSX import pipeline queued null RadExpression entries into pendingCalculationMapExpressions.
CalculationMap.AddBatch() passed those entries into ExpressionDependencyMap.AddExpressionsBatch().
GetOrCreateNodeWithCache() then called Dictionary.TryGetValue() with a null key, which threw the exception.
In Development
Last Updated: 29 Jul 2026 15:10 by ADMIN

When opening an Xlsx file with conditional formatting I get an Exception:

"System.ArgumentNullException: 'Value cannot be null. (Parameter 'formatting')'

at Telerik.Windows.Documents.Spreadsheet.Model.ConditionalFormattings.ConditionalFormattingDxfRule..ctor(DifferentialFormatting formatting)
   at Telerik.Windows.Documents.Spreadsheet.FormatProviders.OpenXml.Xlsx.Model.Elements.Worksheets.ConditionalFormattingRuleElement.GetRule(DifferentialFormatting formatting)
   at Telerik.Windows.Documents.Spreadsheet.FormatProviders.OpenXml.Xlsx.Model.Elements.Worksheets.ConditionalFormattingRuleElement.OnAfterRead(IXlsxWorksheetImportContext context)
   at Telerik.Windows.Documents.FormatProviders.OpenXml.Model.Elements.OpenXmlElementBase.ReadChildElements(IOpenXmlReader reader, IOpenXmlImportContext context)
   at Telerik.Windows.Documents.FormatProviders.OpenXml.Model.Elements.OpenXmlElementBase.Read(IOpenXmlReader reader, IOpenXmlImportContext context)
   at Telerik.Windows.Documents.FormatProviders.OpenXml.Model.Elements.OpenXmlElementBase.ReadChildElements(IOpenXmlReader reader, IOpenXmlImportContext context)
   at Telerik.Windows.Documents.FormatProviders.OpenXml.Model.Elements.OpenXmlElementBase.Read(IOpenXmlReader reader, IOpenXmlImportContext context)
   at Telerik.Windows.Documents.FormatProviders.OpenXml.OpenXmlImporter`1.ImportPartFromArchive(ZipArchiveEntry zipEntry, PartBase part, IOpenXmlImportContext context)
   at Telerik.Windows.Documents.FormatProviders.OpenXml.OpenXmlImporter`1.Import(Stream input, IOpenXmlImportContext context)
   at Telerik.Windows.Documents.Spreadsheet.FormatProviders.OpenXml.Xlsx.XlsxFormatProvider.ImportOverride(Stream input)
   at WpfApp1.MainWindow.StartExcel() in C:\Users\larse\source\repos\WpfApp1\MainWindow.xaml.cs:line 49"

To quote my colleage: "After dissecting the Excel template file, I have isolated what is causing the issue. If conditional formatting is used to disable cell boarders it results in the error, if the conditional formatting is updated to turn the necessary borders white, instead of disabling the report exports correctly, the following screenshot also explains."

In Development
Last Updated: 28 Jul 2026 16:17 by ADMIN
CellSelection.SetValue method causes memory leak of CellReferenceRangeExpression objects in some cases when cell value is referenced by formulas. The memory leak is small, but the remaining CellReferenceRangeExpression continue to listen to some events, causing performance issues when their number become large - the time to set the value increases with each set.
In Development
Last Updated: 27 Jul 2026 11:54 by ADMIN
Scheduled for Scheduled for Q3 2026 (August)
When a worksheet has name that has spaces and a hyperlink to this worksheet is being inserted in Excel, quotes are used to surround the name (ex: 'Sheet 12'!A1) for a valid hyperlink. If quotes are not added, the hyperlink is invalid.
In RadSpreadsheet, it is the opposite: (Sheet 12!A1 is correct, while 'Sheet 12'!A1 is incorrect).
Thus, opening such an exported document from RadSpreadsheet in Excel loads it with incorrect hyperlinks; and importing such an Excel document in RadSpreadsheet loads it with incorrect hyperlinks.

A way to workaround this issue is to modify the hyperlinks on import/export from/to RadSpreadsheet. You can find attached a project demonstrating this approach.
Unplanned
Last Updated: 13 Jul 2026 08:19 by ADMIN
ADMIN
Created by: Deyan
Comments: 19
Category: SpreadProcessing
Type: Feature Request
84
Add support for creating Tables and applying tables styles (predefined ones or custom).
In Development
Last Updated: 02 Jul 2026 08:21 by ADMIN
ADMIN
Created by: Deyan
Comments: 2
Category: SpreadProcessing
Type: Feature Request
23
Add support for array formulas (CellFormulaType "array"). These formulas can accept as parameters and return results containing whole arrays (one- or two- dimensional) of data. In MS Excel, such formulas are inserted with CTRL + SHIFT + Enter, and visualized enclosed with curly brackets ('{' and '}'). 
Completed
Last Updated: 24 Jun 2026 10:48 by ADMIN
Release 2026.2.624 (2026 Q2)
Opening a file where there is a format string with modificator [Color11] causes an ArgumentException "Invalid modificator" This prevents the file from opening.
Completed
Last Updated: 24 Jun 2026 10:31 by ADMIN
Release Scheduled For = 2026.2.624 (2026 Q2)

An error occurs while importing an XLSX document with charts. Here is the stack trace:

   at Telerik.Windows.Documents.Spreadsheet.FormatProviders.OpenXml.Xlsx.Contexts.XlsxWorkbookImportContext.PairSeriesGroupsWithAxes()
   at Telerik.Windows.Documents.FormatProviders.OpenXml.Model.Elements.Chart.PlotAreaElement.CopyPropertiesTo(IOpenXmlImportContext context, DocumentChart chart)
   at Telerik.Windows.Documents.FormatProviders.OpenXml.Model.Elements.Chart.ChartElement.CopyPropertiesTo(IOpenXmlImportContext context, DocumentChart chart)
   at Telerik.Windows.Documents.FormatProviders.OpenXml.Model.Elements.Chart.ChartSpaceElement.OnAfterRead(IOpenXmlImportContext context)
   at Telerik.Windows.Documents.FormatProviders.OpenXml.Model.Elements.OpenXmlElementBase.Read(IOpenXmlReader reader, IOpenXmlImportContext context)
   at Telerik.Windows.Documents.FormatProviders.OpenXml.Model.Parts.ChartPart.Import(IOpenXmlReader reader, IOpenXmlImportContext context)
   at Telerik.Windows.Documents.FormatProviders.OpenXml.Model.Parts.OpenXmlPartBase.Import(Stream stream, IOpenXmlImportContext context)
   at Telerik.Windows.Documents.FormatProviders.OpenXml.OpenXmlImporter`1.ImportPartFromArchive(ZipArchiveEntry zipEntry, PartBase part, IOpenXmlImportContext context)
   at Telerik.Windows.Documents.FormatProviders.OpenXml.OpenXmlImporter`1.Import(Stream input, IOpenXmlImportContext context)
   at Telerik.Windows.Documents.Spreadsheet.FormatProviders.OpenXml.Xlsx.XlsxFormatProvider.ImportOverride(Stream input, CancellationToken cancellationToken)
   at Telerik.Windows.Documents.Spreadsheet.FormatProviders.WorkbookFormatProviderBase.Import(Stream input, Nullable`1 timeout)

Completed
Last Updated: 24 Jun 2026 10:31 by ADMIN
Release Scheduled For = 2026.2.624 (2026 Q2)
This is the stack trace: 
   at Telerik.Windows.Documents.Spreadsheet.Utilities.SpreadsheetHelper.UpdateFloatingImageSize(FloatingShapeBase shape)
   at Telerik.Windows.Documents.Spreadsheet.Utilities.SpreadsheetHelper.CalculateRotatableShapeBoundingRect(Point position, FloatingTransformableShape shape)
   at Telerik.Windows.Documents.Spreadsheet.Layout.RadWorksheetLayout.CalculateShapeBoundingRect(FloatingShapeBase shape)
   at Telerik.Windows.Documents.Spreadsheet.Layout.RadWorksheetLayout.UpdateShapesSizeAndPosition()
   at Telerik.Windows.Documents.Spreadsheet.Layout.RadWorksheetLayout.Measure(CancellationToken cancellationToken)
   at Telerik.Windows.Documents.Spreadsheet.Layout.RadWorksheetLayout.Measure(CellIndex frozenCellIndex, CancellationToken cancellationToken)
   at Telerik.Windows.Documents.Spreadsheet.Model.Workbook.UpdateWorksheetLayout(RadWorksheetLayout worksheetLayout, Worksheet worksheet, Boolean isForPrinting, CancellationToken cancellationToken)
   at Telerik.Windows.Documents.Spreadsheet.Model.Workbook.GetWorksheetLayout(Worksheet worksheet, Boolean isForPrinting, CancellationToken cancellationToken)
   at Telerik.Windows.Documents.Spreadsheet.Model.Workbook.GetWorksheetLayout(Worksheet worksheet, Boolean isForPrinting)
   at Telerik.Windows.Documents.Spreadsheet.FormatProviders.OpenXml.Xlsx.Contexts.XlsxWorksheetImportContext.ImportShapesSizes()
   at Telerik.Windows.Documents.Spreadsheet.FormatProviders.OpenXml.Xlsx.Contexts.XlsxWorksheetImportContext.EndImport(XlsxWorkbookImportContext workbookContext)
   at Telerik.Windows.Documents.Spreadsheet.FormatProviders.OpenXml.Xlsx.Contexts.XlsxWorkbookImportContext.EndImport()
   at Telerik.Windows.Documents.FormatProviders.OpenXml.OpenXmlImporter`1.Import(Stream input, IOpenXmlImportContext context)
   at Telerik.Windows.Documents.Spreadsheet.FormatProviders.OpenXml.Xlsx.XlsxFormatProvider.ImportOverride(Stream input, CancellationToken cancellationToken)
   at Telerik.Windows.Documents.Spreadsheet.FormatProviders.WorkbookFormatProviderBase.Import(Stream input, Nullable`1 timeout)
Completed
Last Updated: 28 May 2026 11:11 by ADMIN
Release 2026.2.519 (2026 Q2)

For example:
Renaming a sheet named "Sheet1" to "Sheet 1", should update formulas references to it to 'Sheet 1!' (notice single quotes), which it does not. The formula =SUM(Sheet1!A2:C2) changes to the invalid expression =SUM(Sheet 1!A2:C2). This breaks formulas referencing that sheet.

Workaround:
Iterate all cells with formulas in the workbook and add single quotes to the beginning and end of sheet name reference. The attached project changes the name of Sheet1 and then fixes all formula references to it by enclosing its name in single quotes.

Completed
Last Updated: 28 May 2026 10:46 by ADMIN
Release 2026.2.519 (2026 Q2)
This happens only on import, that is, if the values are created through UI or through the model, it does not happen. A sheet has a formula A which depends on a cell B and this cell also has a reference to another cell C and the formula A is so placed in the sheet so that it will be imported before cell B. When cell C is updated, the value in A will not be recalculated.
Unplanned
Last Updated: 22 May 2026 09:54 by ADMIN

When a chart is created with RadSpreadProcessing, by default it is exported with legend showing category list. If an xlsx file with a chart with legend showing only series is imported and exported, it will be changed to category list as well. API to switch between the two should be added.

Legend showing category list:

Legend showing series:

Unplanned
Last Updated: 22 May 2026 08:25 by Alexander

Charts with Series-based legends are exported as Categories during import/export.

Completed
Last Updated: 19 May 2026 20:44 by ADMIN
Release 2026.3.519 (2026 Q2)
Code to reproduce: 
            Workbook wb = new Workbook();
            Worksheet worksheet = wb.Worksheets.Add(); 
            PatternFill fill = new PatternFill(PatternType.DiagonalStripe, Colors.Red, Colors.Transparent);
            worksheet.Cells[0, 0].SetFill(fill);

            string outputFilePath = "Sample.pdf";
            File.Delete(outputFilePath);
            Telerik.Windows.Documents.Spreadsheet.FormatProviders.Pdf.PdfFormatProvider pdfFormatProvider =
                new Telerik.Windows.Documents.Spreadsheet.FormatProviders.Pdf.PdfFormatProvider(); 
          
            //export to file
            using (Stream output = File.OpenWrite(outputFilePath))
            {
                pdfFormatProvider.Export(wb, output, TimeSpan.FromSeconds(10));
            }

            Process.Start(new ProcessStartInfo() { FileName = outputFilePath, UseShellExecute = true });
Completed
Last Updated: 14 May 2026 16:33 by ADMIN
Release 2026.2.514 (2026 Q2)
Images don't move with cells when a row/column is inserted.
Completed
Last Updated: 14 May 2026 16:33 by ADMIN
Release 2026.2.514 (2026 Q2)
Created by: Dimitar
Comments: 0
Category: SpreadProcessing
Type: Feature Request
13
Introduce calculation chain functionality. This will provide a better mechanism for handling dependent expressions.
Completed
Last Updated: 02 Apr 2026 11:49 by ADMIN
Release 2026.1.402 (2026 Q1)
Created by: EUNKYUNG
Comments: 0
Category: SpreadProcessing
Type: Feature Request
1
XlsFormatProvider: Add support for hidden rows.
Completed
Last Updated: 02 Apr 2026 11:49 by ADMIN
Release 2026.1.402 (2026 Q1)

Add support for superscript and subscript font effects for cell formatting. Currently, this is not supported by the model and is omitted on import.
			
Completed
Last Updated: 02 Apr 2026 11:48 by ADMIN
Release 2026.1.402 (2026 Q1)
Created by: Christophe
Comments: 2
Category: SpreadProcessing
Type: Feature Request
10
At this point, XlsFormatProvider doesn't support images and they are not imported into Workbook while reading an .xls file.
Completed
Last Updated: 02 Apr 2026 11:47 by ADMIN
Release 2026.1.402 (2026 Q1)
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