DefaultConnectionStringProvider Class

Enables you to resolve connection strings by their names at runtime in .NET Core applications.

Namespace: DevExpress.DataAccess

Assembly: DevExpress.Data.v20.2.dll

NuGet Packages: DevExpress.Data, DevExpress.WindowsDesktop.Data

Declaration

C#

public class DefaultConnectionStringProvider

VB.NET

Public Class DefaultConnectionStringProvider

Remarks

In ASP.NET Core applications, the default connection string provider implementation uses the IConfiguration service to read connection strings. Applications created based on ASP.NET Core templates call the CreateDefaultBuilder method in the Program.cs file to register this service. If the IConfiguration service is not registered, the default provider searches the appsettings.json file in the current directory and reads connection strings from the file’s ConnectionStrings section.

You can override the default connection string provider to get connection strings from a set of different configuration sources, such as appsettings.Development.json, connectionStrings.json, in-memory collection, etc.

1. Create a custom configuration and load connection strings from all the required sources. For instance, create the ConfigurationBuilder class instance and use its extension methods (AddJson, AddInMemoryCollection, etc.) See Configuration in ASP.NET Core for more information.

   C#

   using System.Collections.Generic;
   using Microsoft.Extensions.Configuration;
   
   public IDictionary<string, string> GetGlobalConnectionStrings() {
     var connectionStrings = new Dictionary<string, string> {
       [$"ConnectionStrings:VehiclesInMemory"] = "XpoProvider=SQLite;Data Source=Data/vehicles.db",
       [$"ConnectionStrings:CarsInMemory"] = "XpoProvider=SQLite;Data Source=Data/cars.db;"
     };
     return new ConfigurationBuilder()
       .SetBasePath(hostingEnvironment.ContentRootPath)
       .AddJsonFile("appsettings.json", optional: false, reloadOnChange: true)
       .AddJsonFile($"appsettings.{hostingEnvironment.EnvironmentName}.json", optional: true)
       .AddInMemoryCollection(connectionStrings)
       .AddEnvironmentVariables()
       .Build()
       .GetSection("ConnectionStrings")
       .AsEnumerable(true)
       .ToDictionary(x => x.Key, x => x.Value);
   }
   

2. Call the static DefaultConnectionStringProvider.AssignConnectionStrings method at application startup after the UseDevExpressControls method call to register connection strings globally.

   C#

   using DevExpress.DataAccess;
   
   public class Startup {
     public void Configure(IApplicationBuilder app, IHostingEnvironment env) {
         // ...
         app.UseDevExpressControls();
         DefaultConnectionStringProvider.AssignConnectionStrings(GetGlobalConnectionStrings());
         // ...
     }
   
   }
   

Tip

Online Example: Report Designer - How to read connection strings from different configuration sources in an ASP.NET Core application

Inheritance

Object

DefaultConnectionStringProvider