Enhances Entity Framework Core with functional programming patterns and
DDD-friendly features. Includes base entity classes, soft delete support, audit trails, query
filters, optimistic concurrency, PostgreSQL integration, query performance monitoring, and
domain event handling. Perfect for building maintainable and scalable data access layers in
modern .NET applications.
CSharpEssentials is a comprehensive ecosystem of .NET libraries designed to modernize C# development. It bridges the gap between Object-Oriented and Functional Programming, providing robust tools for error handling, domain modeling, and enterprise application development.
Goal: Make C# code more expressive, safer, and easier to test without sacrificing performance.
📦 Ecosystem Overview
CSharpEssentials is modular. You can use the meta-package to get everything, or install specific modules to keep dependencies light.
Attributes for controlling Enum serialization behavior.
🚀 Getting Started
Install the main package to get the core functional tools:
dotnet add package CSharpEssentials
Or pick individual packages as needed (e.g., dotnet add package CSharpEssentials.Results).
💡 Feature Highlights
1. Functional Error Handling (Results & Errors)
Stop throwing exceptions for flow control. Use Result<T> to express success or failure explicitly.
using CSharpEssentials.ResultPattern;
using CSharpEssentials.Errors;
public Result<User> RegisterUser(string email)
{
if (string.IsNullOrEmpty(email))
return Error.Validation("User.EmailRequired", "Email cannot be empty.");
if (_repo.Exists(email))
return Error.Conflict("User.Exists", "User already exists.");
var user = new User(email);
return user; // Implicit conversion to Result<User>
}
2. Safe Optionals (Maybe)
Eliminate NullReferenceException by explicitly modeling the absence of a value.
using CSharpEssentials.Maybe;
public Maybe<User> GetUserById(Guid id)
{
var user = _repo.Find(id);
return user; // Implicit conversion from User?
}
// Chaining with LINQ
var zipCode = GetUserById(id)
.Map(u => u.Address)
.Map(a => a.ZipCode)
.GetValueOrDefault("00000");
3. Business Rules Engine
Compose complex logic from simple, reusable rules.
var rule = Rule.And(
new MinimumAgeRule(18),
new KycCompletedRule()
);
var result = RuleEngine.Evaluate(rule, userContext);
4. Robust Web APIs (AspNetCore)
Automatically convert Result failures into standard RFC 7807 Problem Details responses using the Global Exception Handler.
// Program.cs
builder.Services.AddExceptionHandler<GlobalExceptionHandler>();
builder.Services.AddEnhancedProblemDetails();
// Controller
[HttpPost]
public IActionResult Create(CreateUserRequest request)
{
Result<User> result = _service.Create(request);
// Returns 200 OK with data, or 400/404/409 ProblemDetails based on Error Type
return result.ToActionResult();
}
5. Domain Modeling (Entity)
Build rich domain models with built-in Audit logs and Domain Events.
public class Order : EntityBase<Guid>
{
public void MarkAsPaid()
{
Status = OrderStatus.Paid;
Raise(new OrderPaidEvent(Id)); // Domain Event
SetUpdatedInfo(DateTimeOffset.UtcNow, "System"); // Auditing
}
}
🛠️ Development & Publishing
This repository includes a smart build script (build-and-publish-nugets.sh) that manages dependency orders and versioning for all packages.
# Build and Test all packages
./build-and-publish-nugets.sh
# Publish to NuGet (requires API Key)
./build-and-publish-nugets.sh --parallel YOUR_API_KEY
🤝 Contributing
Contributions are welcome! Please read our CONTRIBUTING.md guide.
📄 License
This project is licensed under the MIT License. See the LICENSE file for details.
