IEFContextProviderFactory Interface

When implemented, supplies a service that allows you to obtain the EF Core context from the dependency injection container.

Namespace: DevExpress.DataAccess.Web

Assembly: DevExpress.DataAccess.v24.2.dll

NuGet Package: DevExpress.DataAccess

Declaration

C#

public interface IEFContextProviderFactory

VB.NET

Public Interface IEFContextProviderFactory

Remarks

You can resolve the appropriate Entity Framework Core context from the ASP.NET Core service container for dashboards and reports bound to EFDataSource.

For this, implement the custom service that creates a EF Core context object for the specified data source. Register this service in IServiceCollection to obtain the EF Core context from the DI container.

Example: Reporting for ASP.NET Core - Resolve the Entity Framework Core Context from the DI Container

View Example

Implement the IEFContextProvider and IEFContextProviderFactory interfaces (the CustomEFContextProvider and CustomEFContextProviderFactory classes in this example) to create a service that allows you to get the EF Core Context.

CustomEFContextProvider.cs

using DevExpress.Data.Entity;
using DevExpress.DataAccess.Web;
using System;
using Microsoft.Extensions.DependencyInjection;
namespace WebEFCoreApp.Services {
    public class CustomEFContextProviderFactory : IEFContextProviderFactory {
        private readonly IServiceProvider serviceProvider;
        public CustomEFContextProviderFactory(IServiceProvider serviceProvider) {
            this.serviceProvider = serviceProvider;
        }
        public IEFContextProvider Create() {
            return new CustomEFContextProvider(serviceProvider.CreateScope());
        }
    }
    public class CustomEFContextProvider : IEFContextProvider, IDisposable {
        private readonly IServiceScope scope;
        public CustomEFContextProvider(IServiceScope scope) {
            this.scope = scope;
        }

        public object GetContext(string connectionName, Type contextType) {
            // Returns the context for the specified `EFDataSource.ConnectionName`. 
            if (connectionName == "efCoreConnection")
                return scope.ServiceProvider.GetRequiredService(contextType);
            return null;
        }
        public void Dispose() {
            scope.Dispose();
        }
    }
}

Register the context in the dependency injection container. Call the AddDbContext method in the ConfigureServices method of the Startup class to specify the required connection string. Use the ConfigureServices method of the Startup class to register the factory implementation.

Startup.cs

namespace DXWebApplication1 {
    public class Startup {
        public Startup(IConfiguration configuration, IWebHostEnvironment hostingEnvironment) {
            Configuration = configuration;
        }
        public void ConfigureServices(IServiceCollection services) {
            // ...
            services.ConfigureReportingServices(configurator => {
                configurator.ConfigureWebDocumentViewer(viewerConfigurator => {
                    // ...
                    viewerConfigurator.RegisterEFContextProviderFactory<CustomEFContextProviderFactory>();
                });
                configurator.UseAsyncEngine();
            });
            services.AddDbContext<OrdersContext>(options => options.UseSqlite("Data Source=file:Data/nwind.db"), ServiceLifetime.Transient);
        }
    }
}