Connect a Non-XAF Application to a Middle Tier Security Server (EF Core)

• Mar 27, 2025
• 2 minutes to read

The following steps outline how to connect a non-XAF .NET application to a database through the EF Core-based Middle Tier Security application.

Note

The technique described in this topic was not tested with .NET MAUI and Blazor WebAssembly clients. With these platforms, we recommend that you use our Web API Service on the backend as demonstrated in the following examples on GitHub:

• How to Create a Web API Service Backend for a .NET MAUI Application
• How to Create a Web API Service Backend for a Blazor WebAssembly Application

1. Install the following NuGet package: DevExpress.ExpressApp.EFCore.

2. Create a Middle Tier client:

   // The following code sample sets the Middle Tier server URL to the default value for debug mode
   // This setting may be different in your application
   // You can check this setting in the following Middle Tier project's file: Properties/launchSettings.json
   var middleTierClient = new MiddleTierClientBuilder<MainDemoDbContext>()
       .UseServer(" https://localhost:44319/ ")
       .UsePasswordAuthentication("John", "")
       .Build();
   

3. After the client successfully connects to the Middle Tier server and passes authentication, you can access security permissions for the current user.

   var objectSpace = middleTierClient.CreateObjectSpace();
   bool isReadGranted = middleTierClient.Security.CanRead<Employee>(objectSpace);
   bool isWriteGranted = middleTierClient.Security.CanWrite<Employee>(objectSpace, nameof(Employee.Address1));
   

4. You can use the Middle Tier Security as a database provider to access data through an EF Core DbContext or Object Space:

   // Use DbContext to access data:
   var dbContext = middleTierClient.CreateDbContext();
   var users = dbContext.Employees.ToList();
   
   // Use Object Space to access data:
   var objectSpace = middleTierClient.CreateObjectSpace();
   var users = objectSpace.GetObjectsQuery<Employee>().ToList();
   

5. You need to dispose the Middle Tier client when it is no longer needed:

   middleTierClient.Dispose();
   

Tip

You can use DevExpress Template Kit for Visual Studio to create WinForms and WPF applications that implement the described approach.