Generic Repository for .NET Core

The Generic Repository pattern is used to simplify data access operations in .NET Core applications. This package offers support for CRUD operations, custom queries, Unit of Work for transaction management, pagination, dynamic ordering, and multiple DbContext support.

Features

• CRUD operations with both sync and async support.
• Custom queries via LINQ and Expression trees.
• IIncludableQueryable-based include API — supports ThenInclude, filtered includes, etc.
• Pagination through PagingRequest / PagingResult<T> and IQueryable.ToPagedAsync() extension.
• Dynamic ordering with OrderByProperty("Author.Name") — supports nested properties.
• Unit of Work generic per DbContext (IUnitOfWork<TContext>) with transaction management.
• Multiple DbContext support — register repositories and unit of works per context, no collisions.
• Marker interfaces — auto-detected so you can inject IAppUnitOfWork instead of IUnitOfWork<ApplicationDbContext>.

Installation

dotnet add package MGenericRepository

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1. Define Your Repository

// 1. (Optional) Create a base repository for your application to avoid repeating ApplicationDbContext
public class ApplicationRepository<TEntity> : Repository<TEntity, ApplicationDbContext>
    where TEntity : class
{
    public ApplicationRepository(ApplicationDbContext context) : base(context) { }
}

// 2. Define your entity-specific repository
public interface IProductRepository : IRepository<Product>
{
}

public class ProductRepository : ApplicationRepository<Product>, IProductRepository
{
    public ProductRepository(ApplicationDbContext context) : base(context) { }
}

The Repository<TEntity, TContext> base class binds your repository to a specific DbContext.

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2. Register Services in Program.cs

Single layer / single project

builder.Services.AddDbContext<ApplicationDbContext>(opt =>
    opt.UseSqlServer(builder.Configuration.GetConnectionString("Default")));

builder.Services.AddGenericRepository<ApplicationDbContext>(options =>
{
    // Optional — defaults to the calling assembly if omitted
    // options.RegisterServicesFromAssembly(typeof(ProductRepository).Assembly);
});

Clean Architecture / Onion Architecture

In layered solutions, the interface lives in the Application layer and the implementation lives in the Persistence/Infrastructure layer. Both assemblies must be scanned:

builder.Services.AddDbContext<ApplicationDbContext>(opt =>
    opt.UseSqlServer(builder.Configuration.GetConnectionString("Default")));

builder.Services.AddGenericRepository<ApplicationDbContext>(options =>
{
    var applicationAssembly = typeof(IProductRepository).Assembly;
    var persistenceAssembly = typeof(ProductRepository).Assembly;

    options.RegisterServicesFromAssemblies(applicationAssembly, persistenceAssembly);
});

Multiple DbContexts (modular monolith / CQRS / Identity split)

You can call AddGenericRepository<TContext> multiple times, once per context:

builder.Services.AddDbContext<ApplicationDbContext>(opt => opt.UseSqlServer(appConn));
builder.Services.AddDbContext<CatalogDbContext>(opt => opt.UseNpgsql(catalogConn));

builder.Services.AddGenericRepository<ApplicationDbContext>(options =>
    options.RegisterServicesFromAssemblies(
        typeof(IProductRepository).Assembly,
        typeof(ProductRepository).Assembly));

builder.Services.AddGenericRepository<CatalogDbContext>(options =>
    options.RegisterServicesFromAssemblies(
        typeof(ICategoryRepository).Assembly,
        typeof(CategoryRepository).Assembly));

Each Repository<TEntity, TContext> is registered only against the matching context — no collisions.

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3. Inject the Unit of Work

Single context

Inject IUnitOfWork<TContext> directly:

public class ProductService
{
    private readonly IProductRepository _repository;
    private readonly IUnitOfWork<ApplicationDbContext> _unitOfWork;

    public ProductService(
        IProductRepository repository,
        IUnitOfWork<ApplicationDbContext> unitOfWork)
    {
        _repository = repository;
        _unitOfWork = unitOfWork;
    }

    public async Task<Product> AddProductAsync(Product product, CancellationToken ct)
    {
        await _repository.AddAsync(product, ct);
        await _unitOfWork.SaveChangesAsync(ct);
        return product;
    }
}

Multiple contexts — use marker interfaces

Writing IUnitOfWork<ApplicationDbContext> everywhere is verbose. Define a marker interface in your Application layer — no class needed, the package auto-registers it:

// Application layer
public interface IAppUnitOfWork : IUnitOfWork<ApplicationDbContext> { }
public interface ICatalogUnitOfWork : IUnitOfWork<CatalogDbContext> { }

That's it. No implementation class to write — the package binds these markers to the correct UnitOfWork<TContext> automatically during DI registration.

public class OrderService
{
    public OrderService(IAppUnitOfWork appUow, ICatalogUnitOfWork catalogUow) { ... }
}

Make sure the assembly containing your marker interfaces is registered via RegisterServicesFromAssembly(...) so the scanner can find them.

---

4. Querying

Filter + include + tracking

Include uses the IIncludableQueryable pattern, so ThenInclude works:

var product = await _repository.GetFirstOrDefaultAsyncNoTracking(
    p => p.Id == id,
    include: q => q.Include(p => p.Category)
                   .Include(p => p.Reviews).ThenInclude(r => r.User),
    cancellationToken: ct);

Lists

var products = await _repository.GetListAsync(
    filter: p => p.IsActive,
    include: q => q.Include(p => p.Category),
    cancellationToken: ct);

Building your own query with Query()

When the built-in helpers aren't enough, use Query() to get an IQueryable<T> and compose freely:

var query = _repository.Query(
    filter: p => p.Price > 100,
    include: q => q.Include(p => p.Category));

var topProducts = await query
    .OrderByDescending(p => p.SalesCount)
    .Take(10)
    .ToListAsync(ct);

---

5. Pagination

Through the repository

var request = new PagingRequest
{
    PageNumber = 1,
    PageSize = 20,
    OrderBy = "CreateAppUser.FullName", // nested property paths supported
    IsDesc = true
};

var page = await _repository.GetPagedAsync(
    request,
    filter: p => p.IsActive,
    include: q => q.Include(p => p.CreateAppUser),
    cancellationToken: ct);

// page.Items, page.TotalCount, page.PageNumber, page.PageSize
// page.TotalPages, page.HasPrevious, page.HasNext

On any IQueryable<T> via ToPagedAsync()

If you already have a custom query, paginate it with the extension:

using GenericRepository.Extensions;

var page = await _context.Products
    .AsNoTracking()
    .Where(p => p.IsActive)
    .Include(p => p.Category)
    .ToPagedAsync(new PagingRequest
    {
        PageNumber = 1,
        PageSize = 20,
        OrderBy = "Name"
    }, ct);

Return all records

Pass PageSize = QueryableExtensions.AllRecords (or -1) to skip paging and return everything:

var all = await _repository.GetPagedAsync(
    new PagingRequest
    {
        PageNumber = 1,
        PageSize = QueryableExtensions.AllRecords
    });

Dynamic ordering on its own

using GenericRepository.Extensions;

var ordered = _context.Products
    .OrderByProperty("Category.Name", descending: true);

---

6. Transactions

public async Task TransferAsync(Guid fromId, Guid toId, decimal amount, CancellationToken ct)
{
    await _unitOfWork.BeginTransactionAsync(ct);
    try
    {
        // ... your work ...
        await _unitOfWork.CommitAsync(ct);
    }
    catch
    {
        await _unitOfWork.RollbackAsync(ct);
        throw;
    }
}

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7. Bulk Operations

Insert in batches with AddRangeAsync:

await _repository.AddRangeAsync(products, ct);
await _unitOfWork.SaveChangesAsync(ct);

For bulk update / delete in a single round-trip, use EF Core's native ExecuteUpdateAsync / ExecuteDeleteAsync directly on Query():

await _repository.Query(p => p.IsDiscontinued)
    .ExecuteUpdateAsync(s => s.SetProperty(p => p.IsActive, false), ct);

await _repository.Query(p => p.IsDiscontinued)
    .ExecuteDeleteAsync(ct);

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API Quick Reference

Method	Purpose
Add / AddAsync / AddRange / AddRangeAsync	Insert entities (Sync/Async)
Update / UpdateRange	Update entities
Delete / DeleteRange	Remove entities
GetFirstOrDefault / GetFirstOrDefaultAsync	Get single entity by predicate
GetFirstOrDefaultAsNoTracking / GetFirstOrDefaultAsyncNoTracking	Get single entity (No Tracking)
GetListAsync / GetListAsyncNoTracking	List of entities by predicate
Query	Compose your own IQueryable<T> with optional tracking
GetPagedAsync	Paginated result with optional tracking
Any / AnyAsync	Check existence
CountBy	Count entities matching a predicate
IUnitOfWork<TContext>	BeginTransactionAsync, CommitAsync, RollbackAsync, SaveChangesAsync, SaveChanges

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Breaking Changes (v3.0)

• IUnitOfWork is now generic: IUnitOfWork<TContext>. Update all injection sites.
• AddGenericRepository(...) is now generic: AddGenericRepository<TContext>(...). The UseDbContext<T>() option is removed — pass the context as a generic parameter instead.
• Include parameters now use Func<IQueryable<T>, IIncludableQueryable<T, object>> instead of params Expression<Func<T, object>>[]. Rewrite includes as lambdas: q => q.Include(...).ThenInclude(...).
• GetByExpression / GetByExpressionAsync removed — use GetFirstOrDefault / GetFirstOrDefaultAsync (identical behavior).
• First / FirstAsync / GetFirst / GetFirstAsync removed — use GetFirstOrDefault / GetFirstOrDefaultAsync and handle null explicitly, or call Query().First().
• Sync Where removed — use Query(filter: ...).