Unplanned
Last Updated: 12 Jan 2026 15:27 by ADMIN
ADMIN
Created by: Deyan
Comments: 12
Category: SpreadProcessing
Type: Feature Request
38
Add support for pivot tables.
Unplanned
Last Updated: 12 Jan 2026 12:02 by Paul

Getting an exception message when trying to view a document as a PDF using the PdfFormatProvider which started happening only after upgrading Telerik to the latest version, 7.1.0 in Telerik UI for Blazor.

Exception Message:

width should be greater or equal than 0. (Parameter 'width')

I have copied the stack trace and source of the exception below:

 

Source: Telerik.Documents.Fixed

Stack Trace:    at Telerik.Windows.Documents.Fixed.Model.Editing.Layout.ContentElementLayoutElementBase`1.DrawHighlights(DrawLayoutElementContext context)
   at Telerik.Windows.Documents.Fixed.Model.Editing.Layout.ContentElementLayoutElementBase`1.Draw(DrawLayoutElementContext context)
   at Telerik.Windows.Documents.Fixed.Model.Editing.Block.Draw(IEnumerable`1 lineElements, DrawLayoutElementContext context)
   at Telerik.Windows.Documents.Fixed.Model.Editing.Block.DrawInternal(FixedContentEditor editor, Rect boundingRect)
   at Telerik.Windows.Documents.Fixed.Model.Editing.Block.Telerik.Windows.Documents.Fixed.Model.Editing.Flow.IDrawArrangedElement.DrawArrangedElement(FixedContentEditor editor, Rect boundingRect)
   at Telerik.Windows.Documents.Fixed.Model.Editing.Flow.SectionInfo.DrawArrangedElement(IBlockElement blockElement, Double horizontalOffset, Double verticalOffset)
   at Telerik.Windows.Documents.Fixed.Model.Editing.Utils.SectionInfoExtensions.DrawArrangedElements(SectionInfo section, IList`1 elements)
   at Telerik.Windows.Documents.Fixed.Model.Editing.RadFixedDocumentEditor.Draw()
   at Telerik.Windows.Documents.Fixed.Model.Editing.RadFixedDocumentEditor.StartNewPage(SectionProperties sectionProperties)
   at Telerik.Windows.Documents.Fixed.Model.Editing.RadFixedDocumentEditor.StartNewPage()
   at Telerik.Windows.Documents.Fixed.Model.Editing.RadFixedDocumentEditor.AddBlock(IBlockElement blockElement, CancellationToken cancellationToken)
   at Telerik.Windows.Documents.Flow.FormatProviders.Pdf.Export.PdfExporter.ExportSection(Section section, RadFixedDocumentEditor editor)
   at Telerik.Windows.Documents.Flow.FormatProviders.Pdf.Export.PdfExporter.ExportDocument(RadFlowDocument document, RadFixedDocumentEditor editor)
   at Telerik.Windows.Documents.Flow.FormatProviders.Pdf.Export.PdfExporter.ExportInternal()
   at Telerik.Windows.Documents.Flow.FormatProviders.Pdf.Export.PdfExporter.Export()
   at Telerik.Windows.Documents.Flow.FormatProviders.Pdf.PdfFormatProvider.ExportToFixedDocument(RadFlowDocument document, CancellationToken cancellationToken)
   at Telerik.Windows.Documents.Flow.FormatProviders.Pdf.PdfFormatProvider.ExportOverride(RadFlowDocument document, Stream output, CancellationToken cancellationToken)
   at Telerik.Windows.Documents.Flow.FormatProviders.Pdf.PdfFormatProvider.ExportOverride(RadFlowDocument document, Stream output)
   at Telerik.Windows.Documents.Common.FormatProviders.FormatProviderBase`1.Export(T document, Stream output)
   at Telerik.Windows.Documents.Common.FormatProviders.BinaryFormatProviderBase`1.Export(T document)

Unplanned
Last Updated: 12 Jan 2026 06:56 by Eric Moreau
Created by: Eric Moreau
Comments: 0
Category: SpreadProcessing
Type: Feature Request
1

Currently, RadSpreadProcessing supports the following options:

namespace Telerik.Windows.Documents.Model.Drawing.Charts
{
    /// <summary>
    /// Specifies where a chart legend is placed relative to the plot area.
    /// </summary>
    public enum LegendPosition
    {
        /// <summary>
        /// Positions the legend to the right of the plot area.
        /// </summary>
        Right,

        /// <summary>
        /// Positions the legend below the plot area.
        /// </summary>
        Bottom,

        /// <summary>
        /// Positions the legend to the left of the plot area.
        /// </summary>
        Left,

        /// <summary>
        /// Positions the legend above the plot area.
        /// </summary>
        Top
    }
}

MS Excel supports setting "Top Right" Legend Position:

Unplanned
Last Updated: 09 Jan 2026 10:51 by ADMIN
Created by: Tanya
Comments: 4
Category: Telerik Document Processing
Type: Feature Request
31
Allow customers to create, modify and convert .pptx files.
Unplanned
Last Updated: 09 Jan 2026 09:59 by David
InvalidOperationException is thrown when the parser incorrectly interprets delimiter characters within literal strings as structural tokens instead of string data.
Unplanned
Last Updated: 09 Jan 2026 05:47 by Eric Moreau

Currently, if you have a decimal column in the DataTable, it is imported as a text column in the workbook. It should be preserved as a numeric column after importing.

Note: When importing a DataTable, each of the column's type is checked and a respective cell type is imported. 

 if (dataType.IsValueType && dataType.IsPrimitive && !dataType.IsEnum)
                    {
                        newValue = new NumberCellValue(Convert.ToDouble(value));
                    }
The check ensures only “simple” CLR value types are treated as numbers when importing from DataTable to the worksheet.

IsValueType: filters out reference types.

IsPrimitive: narrows to CLR primitives (sbyte, byte, short, ushort, int, uint, long, ulong, float, double, char, IntPtr, UIntPtr, bool).

!IsEnum: excludes enums.

In this code path, primitives are interpreted as numeric and converted to a Double for NumberCellValue. This avoids trying to numeric-convert arbitrary structs (e.g., guid, TimeSpan, custom structs), which should not be treated as numbers.

Decimal is not primitive, so it falls back to text, losing numeric semantics. This is the reason for the observed behavior.
Unplanned
Last Updated: 30 Dec 2025 07:59 by ismayil

This is the code for import/export which result is illustrated below:

            string inputFilePath = "test1.doc";
            Telerik.Windows.Documents.Flow.Model.RadFlowDocument document;
            Telerik.Windows.Documents.Flow.FormatProviders.Doc.DocFormatProvider doc_provider = new Telerik.Windows.Documents.Flow.FormatProviders.Doc.DocFormatProvider();
            using (Stream input = File.OpenRead(inputFilePath))
            {
                document = doc_provider.Import(input, TimeSpan.FromSeconds(10));
            }

            Telerik.Windows.Documents.Flow.FormatProviders.Docx.DocxFormatProvider docx_provider = new Telerik.Windows.Documents.Flow.FormatProviders.Docx.DocxFormatProvider();
            string outputFilePath = "Exported.docx";
            using (Stream output = File.OpenWrite(outputFilePath))
            { 
                docx_provider.Export(document, output, TimeSpan.FromSeconds(10));
            }

            Process.Start(new ProcessStartInfo() { FileName = outputFilePath, UseShellExecute = true });

Unplanned
Last Updated: 23 Dec 2025 10:20 by Pallav
Created by: Pallav
Comments: 0
Category: WordsProcessing
Type: Feature Request
1
Add support for images as list bullets.
Unplanned
Last Updated: 19 Dec 2025 14:40 by Vitalii
SkiaImageFormatProvider: Blacked out images due to incorrectly resolved clipping.
Unplanned
Last Updated: 05 Dec 2025 08:35 by David
PdfFormatProvider: Incorrect column width for tableGrid tables with merged cells.
Unplanned
Last Updated: 03 Dec 2025 14:24 by Domenico

This is the code for reproducing the incorrect PDF document. If the step with changing the font is commented, the document is exported properly:

 //Step 1: Create an instance of XlsxFormatProvider to import the Excel file
            XlsxFormatProvider xlsxFormatProvider = new XlsxFormatProvider();
            Telerik.Windows.Documents.Spreadsheet.FormatProviders.Pdf.PdfFormatProvider pdfFormatProvider = new Telerik.Windows.Documents.Spreadsheet.FormatProviders.Pdf.PdfFormatProvider();

            Workbook workbook;
            using (FileStream input = new FileStream("Input.xlsx", FileMode.Open))
            {
                workbook = xlsxFormatProvider.Import(input, TimeSpan.FromSeconds(10));
            }

            //Step 2: Export the workbook to PDF RadFixedDocument to modify fonts
            Telerik.Windows.Documents.Spreadsheet.FormatProviders.Pdf.PdfFormatProvider spread_pdf_provider = new Telerik.Windows.Documents.Spreadsheet.FormatProviders.Pdf.PdfFormatProvider();
            RadFixedDocument fixedDocument = spread_pdf_provider.ExportToFixedDocument(workbook, TimeSpan.FromSeconds(10));

            foreach (var page in fixedDocument.Pages)
            {
                foreach (var content in page.Content)
                {
                    if (content is TextFragment text)
                    {
                        // Replace the font with Helvetica or HelveticaBold based on the original font style
                        text.Font = text.Font.Name.ToLower().Contains("bold")
                            ? FontsRepository.HelveticaBold
                            : FontsRepository.Helvetica;
                    }
                }
            }

            //Step 3: Save the modified RadFixedDocument back to PDF
            string outputFileName = "ExportedWorkbook.pdf";
            Telerik.Windows.Documents.Fixed.FormatProviders.Pdf.PdfFormatProvider fixed_pdf_provider = new Telerik.Windows.Documents.Fixed.FormatProviders.Pdf.PdfFormatProvider();
            using (FileStream output = new FileStream(outputFileName, FileMode.Create))
            {
                fixed_pdf_provider.ExportSettings.DocumentUnhandledException += ExportSettings_DocumentUnhandledException;
                fixed_pdf_provider.ExportSettings.FontEmbeddingType = Telerik.Windows.Documents.Fixed.FormatProviders.Pdf.Export.FontEmbeddingType.Subset;
                fixed_pdf_provider.Export(fixedDocument, output, TimeSpan.FromSeconds(10));
            }
            Process.Start(new ProcessStartInfo() { FileName = outputFileName, UseShellExecute = true });

Unplanned
Last Updated: 27 Nov 2025 12:52 by Vitalii

When importing a large document (e.g. 2.3GB) , the library fails to parse int value that exceeds the limit which leads to endless importing:

Unplanned
Last Updated: 27 Nov 2025 12:45 by Yannick Patton

LocalizableException is thrown after removing columns from a workbook with set Print Titles.

Workaround - Remove the PrintTitles before removing the columns:

WorksheetPageSetup pageSetup = workbook.ActiveWorksheet.WorksheetPageSetup;
pageSetup.PrintTitles.RepeatedRows = null;
pageSetup.PrintTitles.RepeatedColumns = null;

 

Unplanned
Last Updated: 27 Nov 2025 08:49 by Petter

HtmlFormatProvider: Styles are not correctly preserved when a <b> tag is applied to the same styled element.

Workaround: Apply bold through CSS instead of using <b>.

Unplanned
Last Updated: 26 Nov 2025 12:41 by ADMIN
Opening a file where there is a format string with modificator [Color11] causes an ArgumentException "Invalid modificator" This prevents the file from opening.
Unplanned
Last Updated: 17 Nov 2025 16:05 by Bart
Unable to obtain cached formula values for formulas whose expressions contain named ranges.
Unplanned
Last Updated: 12 Nov 2025 10:43 by Scott
Created by: Scott
Comments: 0
Category: PdfProcessing
Type: Feature Request
10
Add support for ShadingType 1.
Unplanned
Last Updated: 11 Nov 2025 11:45 by Martin Ivanov
Currently, you cannot sort filtered cell ranges that contain merged cells. This is supported in Excel.
Unplanned
Last Updated: 10 Nov 2025 15:01 by Foxy
Handle the import of documents with an invalid cross-reference stream offset.
Unplanned
Last Updated: 04 Nov 2025 09:29 by EUNKYUNG
Created by: EUNKYUNG
Comments: 0
Category: SpreadProcessing
Type: Feature Request
1
XlsFormatProvider: Add support for hidden rows.
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