SentimentAnalyzer

On-device (offline) Sentiment Analysis for .NET applications

A cross-platform, privacy-first library for sentiment analysis that runs entirely on-device without requiring internet connectivity. Powered by ML.NET 5.0.

✨ Features

• 🔒 Privacy-first - All processing happens on-device, no data leaves your app
• 📴 Fully offline - No internet connection required
• 🚀 Cross-platform - Works on .NET Standard 2.0, .NET 8, .NET 10, MAUI, Blazor, Unity
• ⚡ Fast - Thread-safe singleton pattern for optimal performance
• 📦 Lightweight - Single NuGet package, no external dependencies

📦 Installation

dotnet add package SentimentAnalyzer

Or via Package Manager:

Install-Package SentimentAnalyzer

🚀 Quick Start

using SentimentAnalyzer;

// Analyze sentiment
var result = Sentiments.Predict("This product is amazing!");

Console.WriteLine($"Sentiment: {(result.Prediction ? "Positive" : "Negative")}");
Console.WriteLine($"Confidence: {result.Score:P2}");

📖 API Reference

Sentiments.Predict(string text)

Analyzes the sentiment of the provided text.

Parameters:

• text - The text to analyze

Returns: SentimentPrediction

• Prediction (bool) - true for Positive sentiment, false for Negative sentiment
• Score (float) - Confidence score (0.0 to 1.0)

Example Usage

using SentimentAnalyzer;

// Positive sentiment
var positive = Sentiments.Predict("I love this! Best purchase ever!");
// positive.Prediction = true, positive.Score ≈ 0.95

// Negative sentiment
var negative = Sentiments.Predict("Terrible experience, very disappointed.");
// negative.Prediction = false, negative.Score ≈ 0.12

🎯 Platform Support

Platform	Supported	Target Framework
.NET Framework 4.6.1+	✅	netstandard2.0
.NET Core 2.0+	✅	netstandard2.0
.NET 5/6/7	✅	netstandard2.0
.NET 8 (LTS)	✅	net8.0
.NET 10 (LTS)	✅	net10.0
.NET MAUI	✅	All targets
Blazor Server	✅	All targets
Blazor WebAssembly	✅	netstandard2.0
Unity	✅	netstandard2.0

📋 Use Cases

• Customer Feedback Analysis - Automatically categorize reviews and feedback
• Social Media Monitoring - Track brand sentiment in real-time
• Chatbot Intelligence - Detect user mood and respond appropriately
• Content Moderation - Flag negative or toxic content
• IoT/Edge Devices - Run sentiment analysis on resource-constrained devices
• Air-gapped Environments - Perfect for defense, healthcare, and enterprise use

🔄 Migration from v1.x

Version 2.0 maintains full backward compatibility. No code changes required:

<!-- Just update the version -->
<PackageReference Include="SentimentAnalyzer" Version="2.0.0" />

See CHANGELOG.md for detailed release notes.

📚 Learn More

• Blog Post: On-device Machine Learning with SentimentAnalyzer
• ML.NET Documentation

📄 License

This project is licensed under the MIT License - see the LICENSE file for details.

🤝 Contributing

Contributions are welcome! Please feel free to submit a Pull Request.