DRIT.Spreadsheet

A pure-managed, cross-platform .NET library for creating, reading, manipulating, and converting spreadsheet documents: XLSX, XLS, XLSB, CSV, and TSV. The library provides a formula engine, formatting, charts, tables, pivot tables, protection, encryption, digital signatures, and export workflows without requiring Microsoft Excel or another office installation.

Public examples

This repository contains 58 runnable console examples covering the normal create, load, edit, save, reload, export, and protection workflows. Browse the complete example catalog for source code, generated-output expectations, package-based commands, and current API limitations.

The catalog is organized into foundation, data and analysis, formatting and layout, export and security, and API-gated workflows. Every example uses deterministic data, writes generated files below Out, and verifies its result through a reload, package inspection, or a concise invariant check.

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Table of Contents

• What is DRIT.Spreadsheet?
• Features
• Supported File Formats
• Platform Independence
• Get Started
• Security
• Public Console Examples
• Building and Validation
• Repository Contents
• License

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What is DRIT.Spreadsheet?

DRIT.Spreadsheet is a pure-managed spreadsheet library implemented in C#. It does not depend on Microsoft Excel, Office Interop, LibreOffice, or a third-party spreadsheet engine. Its package model, Open XML reader and writer, legacy binary workbook support, formula calculation, drawing model, and export pipeline are maintained in the product source.

The library supports both ordinary spreadsheet automation and document-quality workflows: calculated formulas, tables and pivots, charts and shapes, workbook protection, AES-256 encryption, XAdES-BES signatures, PDF export, and image rendering.

Features

• Workbook I/O: create, load, save, and reload workbooks from files or streams, with password, warning, and cancellation options.
• Cells and formulas: typed values, merged cells, ranges, shared and array formulas, circular-reference detection, iterative calculation, and broad Excel-function coverage.
• Data workflows: find and replace, sorting, AutoFilter, data validation, DataTable import/export, JSON import/export, CSV/TSV, and Markdown export.
• Formatting and layout: number formats, fonts, borders, fills, rich text, conditional formatting, themes, AutoFit, row and column sizing, grouping, page setup, print settings, headers, footers, and page breaks.
• Workbook structures: worksheets, tables, pivot tables, slicers, defined names, hyperlinks, comments, threaded comments, custom XML, and OLE objects.
• Charts and drawings: chart sheets, bar/column, line, pie, scatter, and other chart types; shapes, pictures, form controls, anchoring, and sparklines.
• Protection and security: worksheet and workbook protection, write protection, ECMA-376 Agile AES-256 encryption, and XAdES-BES digital signatures.
• Conversion and rendering: PDF export, workbook and worksheet-range image export, HTML import/export, and export to GitHub Flavored Markdown.
• Automation: VBA project and module preservation and editing.

Supported File Formats

Format	Read	Write	Notes
XLSX	Yes	Yes	Office Open XML workbook
XLS	Yes	Preservation-only	Legacy Excel binary workbook
XLSB	Yes	Yes	Excel binary workbook
CSV	Yes	Yes	Comma-separated values
TSV	Yes	Yes	Tab-separated values
PDF	No	Yes	Via the integrated DRIT.Pdf companion
PNG, BMP, JPEG, TIFF	No	Yes	Workbook and range image export
EMF	No	Yes	Shared drawing export pipeline
HTML	Yes	Yes	Table-oriented import and export
Markdown	No	Yes	GitHub Flavored Markdown tables
JSON	Yes	Yes	Range and record import/export

PDF export, PDF signing, and image rendering use the integrated DRIT.Pdf and DRIT.Drawing companions.

Platform Independence

DRIT.Spreadsheet targets .NET Framework 4.8, .NET Standard 2.0, and .NET 6.0. It runs on Windows, Linux, and macOS where the target framework and graphics dependencies are supported.

No Microsoft Excel installation or Office Interop assembly is required.

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Get Started

Install from NuGet

Install-Package DRIT.Spreadsheet

Or with the .NET CLI:

dotnet add package DRIT.Spreadsheet

Create and save a workbook

using DRIT.Spreadsheet;

var workbook = new Workbook();
var worksheet = workbook.Worksheets[0];

worksheet.Cells["A1"].Value = "Product";
worksheet.Cells["B1"].Value = "Price";
worksheet.Cells["A2"].Value = "Atlas Server";
worksheet.Cells["B2"].Value = 4899.00;
worksheet.GetRange("A1:B1").Font.Bold = true;

workbook.SaveAs("output.xlsx");

Load and inspect a workbook

using DRIT.Spreadsheet;

var workbook = Workbook.Load("input.xlsx");
Console.WriteLine($"Worksheets: {workbook.Worksheets.Count}");

foreach (var cell in workbook.Worksheets[0].UsedRange.GetAllCells())
		Console.WriteLine($"[{cell.Row.Index},{cell.Column.Index}] = {cell.Value}");

Create a chart

using DRIT.Spreadsheet;
using DRIT.Spreadsheet.Charts;

var workbook = new Workbook();
var worksheet = workbook.Worksheets[0];
worksheet.GetRange("A1:B3").SetValue(new object[,]
{
		{ "Month", "Sales" },
		{ "Jan", 1000 },
		{ "Feb", 1500 }
});

var chart = worksheet.Charts.Add<BarChart>("D2");
chart.DataSource = "Sheet1!$A$1:$B$3";
chart.AddTitle();
chart.AddLegend();

workbook.SaveAs("chart.xlsx");

Export to PDF or an image

using DRIT.Spreadsheet;
using DRIT.Spreadsheet.Export.Image;

var workbook = Workbook.Load("input.xlsx");

workbook.SaveAsPdf("output.pdf");
workbook.SaveAsImage("output\\{sheet}_page{page}.png", new WorkbookImageSaveOptions
{
		Format = ImageExportFormat.Png,
		Dpi = 150,
		ForceGridLines = true
});

PDF and image export require the integrated renderer packages. PDF export also requires a valid DRIT.Pdf license at runtime; a successful package restore does not provide that license.

Encrypt a workbook

using DRIT.Spreadsheet;

var workbook = new Workbook();
workbook.Worksheets[0].Cells["A1"].Value = "Confidential";
workbook.SaveAs("encrypted.xlsx", new XlsxSaveOptions
{
		EncryptionMode = XlsxEncryptionMode.Ecma376Agile,
		Password = "open-password"
});

var loaded = Workbook.Load("encrypted.xlsx",
		new XlsxLoadOptions { Password = "open-password" });

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Security

Capability	Implementation
AES-256 encryption	XlsxSaveOptions with EncryptionMode.Ecma376Agile and Password
Worksheet protection	Worksheet.Protection.Protect() with granular permission flags
Workbook protection	Structure and window protection with password hashing
Write protection	ReadOnlyRecommended and file-sharing metadata
XAdES-BES signing	XlsxDigitalSignatureSaveOptions with a PFX certificate and signer role
Validate signatures	Workbook.ListDigitalSignatures(path)
Remove signatures	Workbook.RemoveDigitalSignatures(path)
PDF signing and encryption	Options provided by the integrated DRIT.Pdf export workflow

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Public Console Examples

The DRIT.Spreadsheet examples catalog contains one focused project per workflow:

Area	Representative examples
Foundation	GettingStarted, Reading, Writing, Preservation, CellValues, RangeOperations, RowColumnOperations, WorksheetManagement
Data and analysis	Tables, AutoFilter, Sorting, DataValidation, FindAndReplace, Hyperlinks, DefinedNames, DataTableImportExport, CsvImportExport, PivotTables, Slicers, JsonImportExport, MarkdownExport
Formatting and layout	Formatting, StylesAndThemes, RichText, PageSetup, HeadersAndFooters, RightToLeftText, UnitConversion, ConditionalFormatting
Charts and drawings	Charts, ChartTypes, ChartFormatting, ChartSheets, Shapes, ShapeAnchoring, Pictures, FormControls, Sparklines, Ole
Protection and metadata	DocumentProperties, WorkbookProtection, WorksheetProtection, WriteProtection, Encryption, DigitalSignature, CustomXml, Vba
Conversion and rendering	HtmlImportExport, PdfExport, ImageExport, ProgressAndCancellation
Other workbook features	FreezeSplit, WorksheetView, Comments, ThreadedComments, Scenarios, EcmaFormulas

The Phase 5 examples HtmlImportExport, ImageExport, ThreadedComments, and Scenarios use APIs that may require a newer package release and are marked package-gated until the released package exposes the same surface. The catalog also documents package-inspection checks for pivot tables, slicers, charts, custom XML, signatures, and metadata where object-model reload is not the complete verification boundary.

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Building and Validation

The examples use released NuGet packages and are intended to build from a clean public checkout:

dotnet build .\DRIT.Spreadsheet.Examples.Console\DRIT.Spreadsheet.Examples.sln -f net8.0 --nologo

The DigitalSignature and Vba examples use net48 because their signing and VBA paths are platform-gated. PDF and image examples require the integrated renderer packages, and PDF execution requires a valid DRIT.Pdf license. Generated files are written under DRIT.Spreadsheet.Examples.Console/Out, which is ignored by Git.

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Repository Contents

Path	Purpose
DRIT.Spreadsheet.Examples.Console/	Standalone projects consuming the NuGet packages

Documentation and Resources

• NuGet package
• Product page
• API documentation
• Support forums

License

DRIT.Spreadsheet is a closed-source, commercial product of DR-IT Ltd. This repository contains examples and documentation only. The examples are provided for evaluation and learning. See the product page for licensing terms.

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