BlazorOrderApp — Orders & Order Items Master-Detail

A production-ready Blazor Server application with MudBlazor, EF Core (SQL Server), Repository + Specification patterns, and FluentValidation.

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🏗️ Architecture

BlazorOrderApp/
├── Domain/
│   ├── Entities/
│   │   ├── Order.cs               # Master entity + OrderStatus enum
│   │   └── OrderItem.cs           # Detail entity
│   └── Specifications/
│       ├── BaseSpecification.cs   # Generic specification base
│       └── OrderSpecifications.cs # Filtered, paged, by-id specs
│
├── Application/
│   ├── DTOs/
│   │   └── OrderDtos.cs           # OrderDto, OrderItemDto, CreateOrderDto, PagedResult<T>
│   ├── Interfaces/
│   │   ├── IRepository.cs         # Generic repository contract
│   │   ├── IOrderRepository.cs    # Order-specific contract
│   │   └── IOrderService.cs       # Service contract
│   ├── Services/
│   │   └── OrderService.cs        # All CRUD + business logic
│   └── Validators/
│       └── OrderValidators.cs     # FluentValidation rules
│
├── Infrastructure/
│   ├── Data/
│   │   ├── AppDbContext.cs         # EF Core DbContext with seed data
│   │   └── SpecificationEvaluator.cs # Translates spec → IQueryable
│   └── Repositories/
│       ├── Repository.cs           # Generic EF Core implementation
│       └── OrderRepository.cs      # Order-specific (GenerateOrderNumber)
│
└── Web/
    ├── App.razor                   # Root HTML shell
    ├── Routes.razor
    ├── _Imports.razor
    ├── Components/
    │   ├── Layout/
    │   │   └── MainLayout.razor    # AppBar + Drawer + MudTheme
    │   ├── Pages/
    │   │   ├── Index.razor         # Dashboard with KPI cards
    │   │   ├── Orders.razor        # Master list + filter + pagination
    │   │   └── OrderDetail.razor   # Detail view + inline item CRUD
    │   ├── Dialogs/
    │   │   ├── OrderDialog.razor   # Create / Edit order dialog
    │   │   ├── OrderItemDialog.razor # Add / Edit single item
    │   │   └── ConfirmDialog.razor # Reusable delete confirmation
    │   └── Shared/
    │       └── OrderStatusChip.razor # Colored status badge
└── Program.cs                      # DI, EF, MudBlazor registration

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🚀 Getting Started

1. Configure the connection string

Edit appsettings.json:

"ConnectionStrings": {
  "DefaultConnection": "Server=(localdb)\\mssqllocaldb;Database=BlazorOrderApp;Trusted_Connection=True;"
}

2. Apply EF Core migrations

# Add first migration
dotnet ef migrations add InitialCreate --output-dir Infrastructure/Data/Migrations

# Apply to database (also runs automatically on startup via MigrateAsync)
dotnet ef database update

3. Run

dotnet run

Navigate to https://localhost:5001

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✨ Features

Feature	Implementation
Master list	Orders.razor — MudTable with server-side data
Detail view	OrderDetail.razor — customer card + items table
Create order	OrderDialog.razor — dynamic item rows, live total
Edit order	Same dialog, pre-populated
Delete order	ConfirmDialog.razor — guard against accidents
Add / edit / delete items	OrderItemDialog.razor + inline icon actions
Update status	Inline MudSelect on detail page
Filtering	Search term, status, date range
Pagination	OrdersFilteredSpecification with Skip/Take
Validation	FluentValidation — errors shown inline
Repository pattern	IRepository<T> + IOrderRepository
Specification pattern	BaseSpecification<T> + SpecificationEvaluator
Seed data	3 orders × multiple items in OnModelCreating
Dashboard	KPI cards (total, pending, delivered, revenue)

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🔑 Key Patterns

Specification

// Define the query as a reusable object
var spec = new OrdersFilteredSpecification(filter);
var orders = await _orderRepo.GetAsync(spec);

Repository

// Injected via IOrderRepository
await _orderRepo.AddAsync(order);
await _orderRepo.UpdateAsync(order);
await _orderRepo.DeleteAsync(order);

FluentValidation (wired manually in dialogs)

var validator = new CreateOrderValidator();
var result = await validator.ValidateAsync(model);
if (!result.IsValid) { /* show errors */ }