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Aspose.Words FOSS for .NET

Create, read, and edit Word documents from .NET — free and open-source, built from the genuine Aspose.Words engine, no Microsoft Word required.

Aspose.Words FOSS for .NET Aspose.Words FOSS
for .NET

Documentation GitHub

Open-Source .NET Library for Word Documents

Aspose.Words FOSS for .NET is a MIT-licensed pure-C# library for working with Word .docx files. It is not a rewrite or a wrapper: it is the actual Aspose.Words for .NET source code, the same document engine that has processed Word documents in production since 2003, reduced down to a free, open-source core.

The library exposes the same Document Object Model used by the commercial product — Document, DocumentBuilder, Section, Paragraph, Run, Table, and hundreds of related classes. Create documents from scratch or open existing ones, manipulate text, tables, lists, styles, headers and footers, bookmarks, comments, and footnotes, and convert between DOCX, Markdown, and plain text. A full field evaluation engine is included, so fields such as DATE, DOCPROPERTY, and mail-merge fields update programmatically (fields that depend on page layout, such as page numbers, evaluate to placeholder values since page layout itself is not part of this edition).

The library targets .NET Standard 2.0, so it runs on .NET Framework 4.6.2+, .NET 6/8/10, on Windows, Linux, and macOS, with no native dependencies. A NuGet package has not been published yet — build the library from source (see below). Developers who need the complete enterprise API — full page layout and rendering, image and PDF output, and additional format converters — can use Aspose.Words for .NET alongside these open-source resources.

Document Creation and Editing

  • Create and open DOCX: Build documents from scratch or load existing .docx files via new Document() and new Document(path).
  • High-level authoring: Use DocumentBuilder to insert text, move the cursor to sections and bookmarks, and apply font, paragraph, and page formatting in a few calls.
  • Full document object model: Walk the node tree directly, or subclass DocumentVisitor to process every node type.
  • Combine and reorganize: Append, clone, and import content between documents using the high-level DocumentBuilder and node APIs.
  • Find and replace: Regular-expression and formatting-aware find/replace across the document.

Where Aspose.Words FOSS Can Be Used

  • Document generation: Produce reports, letters, and contracts from templates without Office installed.
  • Content migration: Read existing DOCX files and restructure, re-style, or extract their content.
  • Format conversion pipelines: Convert DOCX to Markdown or plain text for search indexing or static-site generation.
  • Serverless backends: Process Word documents inside Docker containers or cloud functions with no COM automation.
  • Batch document processing: Apply the same edits across large collections of DOCX files.

Fields, Tables, and Document Structure

  • Field evaluation engine: Update fields such as DATE, DOCPROPERTY, REF, SEQ, and mail-merge fields programmatically via the full field engine.
  • Tables and conditional formatting: Build and style tables with Table/Row/Cell, including per-region conditional formatting via ConditionalStyle.
  • Lists: Create, copy, and retrieve numbered and bulleted list definitions through ListCollection and ListFormat.
  • Tracked changes: Inspect, accept, or reject revisions using the RevisionCollection API.
  • Document protection: Apply password protection and read-only enforcement through the DocumentSecurity enum.

Developer Experience

Aspose.Words FOSS is pure C# targeting .NET Standard 2.0 — no native extensions to compile, no system packages to install. A NuGet package is coming soon; until then, build from source with a single dotnet build command.

The API mirrors the commercial Aspose.Words for .NET object model, so the official documentation and examples largely apply within this edition’s supported feature set. It is MIT-licensed and open-source on GitHub.

Create a Document with a Chart

Use DocumentBuilder.InsertChart() to add a chart shape to a document, then access its Chart object to configure series data. Clear the default generated series before adding real data.

git clone https://github.com/aspose-words-foss/Aspose.Words-FOSS-for-.NET.git
cd Aspose.Words-FOSS-for-.NET
dotnet build Aspose.Words.sln -c Release

using Aspose.Words;
using Aspose.Words.Drawing.Charts;

Document doc = new Document();
DocumentBuilder builder = new DocumentBuilder(doc);

Shape shape = builder.InsertChart(ChartType.Line, 432, 252);
Chart chart = shape.Chart;

// Delete default generated series.
chart.Series.Clear();

string[] categories = new string[] { "AW Category 1", "AW Category 2", "AW Category 3" };
chart.Series.Add("AW Series 1", categories, new double[] { 4.3, 2.5, 3.5 });

doc.Save("chart.docx");

Frequently Asked Questions

What is the licensing model for Aspose.Words FOSS for .NET?

Aspose.Words FOSS for .NET is released under the MIT License. You may use it in personal, commercial, and closed-source projects free of charge, with no royalty and no runtime license key or activation step.

How do I install Aspose.Words FOSS for .NET?

A NuGet package has not been published yet, so the library must be built from source. Clone the repository and build the solution in Release configuration, then add a project reference to Aspose.Words.csproj from your own application.

Which file formats can Aspose.Words FOSS for .NET read and write?

DOCX, DOCM, DOTX, DOTM, and Flat OPC (plus its macro-enabled and template variants) for both load and save, sharing the same OOXML reader/writer, plus Markdown and plain text for both load and save.

Can Aspose.Words FOSS for .NET export documents to PDF, XPS, or image formats?

No. This edition does not include the page-layout and rendering subsystem, so Document.Save() cannot export to PDF, XPS, or image formats. Save to DOCX, DOCM, DOTX, DOTM, Flat OPC, Markdown, or plain text instead.

Can Aspose.Words FOSS for .NET create a digital signature on a document?

No. This edition can inspect and verify digital signatures already attached to a .docx file, but it cannot create new signatures. A signing workflow requires the commercial Aspose.Words for .NET.

Does this edition support executing mail merges, LINQ Reporting, or comparing documents?

No. Mail merge execution, LINQ Reporting, document comparison, and embedded-font subsetting are not included in this FOSS edition.

  

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