Aspose.Words Document Comparer for .NET

Aspose.Words Document Comparer for .NET provides developers with a powerful tool to compare two Word documents and generate revisions that highlight every detected difference. Whether for legal, technical, or editorial review, this plugin ensures accurate tracking of text edits, formatting changes, and structural modifications directly in your .NET applications.

Installation and Setup

  1. Install the NuGet package Aspose.Words Document Comparer into your project.
  2. Apply metered licensing at application startup ( Metered Licensing Guide ).
  3. See the Installation Guide for prerequisites and detailed steps.

Supported Environments:

  • OS: Windows, Linux, macOS
  • Frameworks: .NET Framework, .NET Standard, .NET Core, .NET 5/6+, Mono
  • IDEs: Microsoft Visual Studio (2010–2022), Xamarin, MonoDevelop

Quick Start: Compare Documents in .NET 

using Aspose.Words;

var docA = new Document(MyDir + "Blank.docx");
var docB = new Document(MyDir + "Document.docx");

// Compare documents. Differences are added as revisions to docA
docA.Compare(docB, "User", DateTime.Now, new CompareOptions { IgnoreFormatting = true });

// Inspect revisions
foreach (Revision revision in docA.Revisions)
{
    Console.WriteLine("Type: " + revision.RevisionType);
    Console.WriteLine("Author: " + revision.Author);
    Console.WriteLine("Date: " + revision.DateTime);
    Console.WriteLine("Revision text: " + revision.ParentNode.ToString(SaveFormat.Text));
}

This snippet demonstrates comparing two documents and iterating through the generated revisions.

Features and Functionalities

Core Document Comparison

  • Compares DOC, DOCX, RTF, HTML, PDF, OpenOffice, Markdown, and more.
  • Inserts insertions, deletions, and formatting changes from the second document into the first.
  • Preserves original content and applies Word’s familiar Track Changes style.

Revision Tracking and Management

  • Categorizes revisions as Insert, Delete, or FormatChange.
  • Supports programmatic accept/reject operations.
  • Allows iteration for building custom reports or summaries.

Custom Comparison Settings

  • Toggle case sensitivity.
  • Choose whether to track whitespace changes (spaces, tabs, breaks).
  • Control comparison granularity: character, word, or paragraph level.
  • Skip nodes like comments, bookmarks, or headers.

Element-Level Comparison

  • Text: Detects additions, deletions, and moved text.
  • Formatting: Identifies font, paragraph, and style changes.
  • Tables: Tracks row/column insertions, deletions, and cell merges/splits.
  • Objects: Flags inserted, deleted, or repositioned images, shapes, and OLE objects.

Performance and Scalability

  • Stream-based APIs allow comparing very large documents efficiently.
  • Multi-threaded comparisons supported for batch processing.
  • Configurable memory footprint with load and save options.

Best Practices

  • Apply licensing early to avoid evaluation messages.
  • Normalize documents (styles, remove tracked changes) before comparison.
  • Adjust whitespace/case sensitivity to reduce false positives.
  • Use the Revisions collection for structured change logs.
  • For bulk workloads, run comparisons asynchronously and manage concurrency.

Troubleshooting Common Issues

Unexpected results or missing changes? ✔ Check document integrity and formatting consistency.

Evaluation watermark or limited functionality? ✔ Ensure licensing is correctly applied.

Slow performance with large documents? ✔ Use stream-based APIs and enable parallel processing where possible.

Frequently Asked Questions

Q: What is Aspose.Words Document Comparer for .NET? A plugin for detecting differences between documents and applying them as revisions for review.

Q: Which file formats are supported? DOC, DOCX, RTF, HTML, PDF, OpenOffice formats, Markdown, and images (JPG, PNG, etc.).

Q: Can I accept or reject revisions programmatically? Yes. The API supports accepting/rejecting revisions in bulk or individually.

Q: How does this integrate with Aspose.Words? It works directly with Aspose.Words document objects, ensuring seamless integration with existing workflows.

Q: Which industries benefit from this tool? Legal, finance, publishing, and enterprise sectors use it for audits, compliance, and editorial review.