Open Source Web Application Framework for ASP.NET Core
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//[doc-seo]
{
    "Description": "ABP Low-Code System: Build admin panels with auto-generated CRUD UI, APIs, and permissions using C# attributes and Fluent API. No boilerplate code needed."
}

Low-Code System

The ABP Low-Code System lets you define entities using C# attributes or Fluent API and automatically generates:

  • Database tables (via EF Core migrations)
  • CRUD REST APIs (Get, GetList, Create, Update, Delete)
  • Permissions (View, Create, Update, Delete per entity)
  • Menu items (auto-added to the admin sidebar)
  • Full Blazor UI (data grid, create/edit modals, filters, foreign key lookups)

No need to write entity classes, DTOs, application services, repositories, or UI pages manually.

Why Low-Code?

Traditionally, adding a new entity to an ABP application requires:

  1. Entity class in Domain
  2. DbContext configuration in EF Core
  3. DTOs in Application.Contracts
  4. AppService in Application
  5. Controller in HttpApi
  6. Razor/Blazor pages in UI
  7. Permissions, menu items, localization

With Low-Code, a single C# class replaces all of the above:

[DynamicEntity]
[DynamicEntityUI(PageTitle = "Products")]
public class Product
{
    [DynamicPropertyUnique]
    public string Name { get; set; }

    [DynamicPropertyUI(DisplayName = "Unit Price")]
    public decimal Price { get; set; }

    public int StockCount { get; set; }

    [DynamicForeignKey("MyApp.Categories.Category", "Name")]
    public Guid? CategoryId { get; set; }
}

Run dotnet ef migrations add Added_Product and start your application. You get a complete Product management page with search, filtering, sorting, pagination, create/edit forms, and foreign key dropdown — all auto-generated.

Getting Started

1. Register Your Assembly

In your Domain module, register the assembly that contains your [DynamicEntity] classes:

public override void ConfigureServices(ServiceConfigurationContext context)
{
    AbpDynamicEntityConfig.SourceAssemblies.Add(
        new DynamicEntityAssemblyInfo(typeof(YourDomainModule).Assembly)
    );
}

2. Configure DbContext

Call ConfigureDynamicEntities() in your DbContext:

protected override void OnModelCreating(ModelBuilder builder)
{
    base.OnModelCreating(builder);
    builder.ConfigureDynamicEntities();
}

3. Define Your First Entity

[DynamicEntity]
[DynamicEntityUI(PageTitle = "Customers")]
public class Customer
{
    public string Name { get; set; }

    [DynamicPropertyUI(DisplayName = "Phone Number")]
    public string Telephone { get; set; }

    [DynamicForeignKey("Volo.Abp.Identity.IdentityUser", "UserName")]
    public Guid? UserId { get; set; }
}

4. Add Migration and Run

dotnet ef migrations add Added_Customer
dotnet ef database update

Start your application — the Customer page is ready.

Two Ways to Define Entities

Define entities as C# classes with attributes. You get compile-time checking, IntelliSense, and refactoring support:

[DynamicEntity]
[DynamicEntityUI(PageTitle = "Orders")]
public class Order
{
    [DynamicForeignKey("MyApp.Customers.Customer", "Name", ForeignAccess.Edit)]
    public Guid CustomerId { get; set; }

    public decimal TotalAmount { get; set; }
    public bool IsDelivered { get; set; }
}

[DynamicEntity(Parent = "MyApp.Orders.Order")]
public class OrderLine
{
    [DynamicForeignKey("MyApp.Products.Product", "Name")]
    public Guid ProductId { get; set; }

    public int Quantity { get; set; }
    public decimal Amount { get; set; }
}

See Fluent API & Attributes for the full attribute reference.

model.json (Declarative)

Alternatively, define entities in a JSON file without writing C# classes:

{
  "entities": [
    {
      "name": "MyApp.Customers.Customer",
      "displayProperty": "Name",
      "properties": [
        { "name": "Name", "isRequired": true },
        { "name": "Telephone", "ui": { "displayName": "Phone Number" } }
      ],
      "ui": { "pageTitle": "Customers" }
    }
  ]
}

See model.json Structure for the full specification.

Both approaches can be combined. The three-layer configuration system merges Attributes, JSON, and Fluent API with clear priority rules.

Key Features

Feature Description Documentation
Attributes & Fluent API Define entities with C# attributes and configure programmatically Fluent API & Attributes
model.json Declarative entity definitions in JSON model.json Structure
Reference Entities Link to existing entities like IdentityUser Reference Entities
Interceptors Pre/Post hooks for Create, Update, Delete with JavaScript Interceptors
Scripting API Server-side JavaScript for database queries and CRUD Scripting API
Custom Endpoints REST APIs with JavaScript handlers Custom Endpoints
Foreign Access View/Edit related entities from the parent's UI Foreign Access
Export Export entity data to Excel (XLSX) or CSV See below

Export (Excel / CSV)

The Low-Code System provides built-in export functionality for all dynamic entities. Users can export filtered data to Excel (XLSX) or CSV directly from the Blazor UI.

How It Works

  1. The client calls GET /api/low-code/entities/{entityName}/download-token to obtain a single-use download token (valid for 30 seconds).
  2. The client calls GET /api/low-code/entities/{entityName}/export-as-excel or GET /api/low-code/entities/{entityName}/export-as-csv with the token and optional filters.

API Endpoints

Endpoint Description
GET /api/low-code/entities/{entityName}/download-token Get a single-use download token
GET /api/low-code/entities/{entityName}/export-as-excel Export as Excel (.xlsx)
GET /api/low-code/entities/{entityName}/export-as-csv Export as CSV (.csv)

Export requests accept the same filtering, sorting, and search parameters as the list endpoint. Server-only properties are automatically excluded, and foreign key columns display the referenced entity's display value instead of the raw ID.

Custom Commands and Queries

The Low-Code System allows you to replace or extend the default CRUD operations by implementing custom command and query handlers in C#.

Custom Commands

Create a class that implements ILcCommand<TResult> and decorate it with [CustomCommand]:

[CustomCommand("Create", "MyApp.Products.Product")]
public class CustomProductCreateCommand : LcCommandBase<DynamicEntityDto>
{
    public override async Task<DynamicEntityDto> ExecuteWithResultAsync(DynamicCommandArgs commandArgs)
    {
        // Your custom create logic here
        // ...
    }
}
Parameter Description
commandName The command to replace: "Create", "Update", or "Delete"
entityName Full entity name (e.g., "MyApp.Products.Product")

Custom Queries

Create a class that implements ILcQuery<TResult> and decorate it with [CustomQuery]:

[CustomQuery("List", "MyApp.Products.Product")]
public class CustomProductListQuery : ILcQuery<DynamicQueryResult>
{
    public async Task<DynamicQueryResult> ExecuteAsync(DynamicQueryArgs queryArgs)
    {
        // Your custom list query logic here
        // ...
    }
}
Parameter Description
queryName The query to replace: "List" or "Single"
entityName Full entity name (e.g., "MyApp.Products.Product")

Custom commands and queries are automatically discovered and registered at startup. They completely replace the default handler for the specified entity and operation.

Internals

Domain Layer

  • DynamicModelManager: Singleton managing all entity metadata with a layered configuration architecture (Code > JSON > Fluent > Defaults).
  • EntityDescriptor: Entity definition with properties, foreign keys, interceptors, and UI configuration.
  • EntityPropertyDescriptor: Property definition with type, validation, UI settings, and foreign key info.
  • IDynamicEntityRepository: Repository for dynamic entity CRUD operations.

Application Layer

  • DynamicEntityAppService: CRUD operations for all dynamic entities (Get, GetList, Create, Update, Delete, Export).
  • DynamicEntityUIAppService: UI definitions, menu items, and page configurations. Provides:
    • GetUiDefinitionAsync(entityName) — Full UI definition (filters, columns, forms, children, foreign access actions, permissions)
    • GetUiCreationFormDefinitionAsync(entityName) — Creation form fields with validation rules
    • GetUiEditFormDefinitionAsync(entityName) — Edit form fields with validation rules
    • GetMenuItemsAsync() — Menu items for all entities that have a pageTitle configured (filtered by permissions)
  • DynamicPermissionDefinitionProvider: Auto-generates permissions per entity.
  • CustomEndpointExecutor: Executes JavaScript-based custom endpoints.

Database Providers

Entity Framework Core: Dynamic entities are configured as EF Core shared-type entities via the ConfigureDynamicEntities() extension method.

See Also