implementing Configuring EF Core to Use a Custom Database Connection String in ASP.NET Core 7
I'm stuck on something that should probably be simple. I'm having trouble configuring Entity Framework Core to use a custom database connection string in my ASP.NET Core 7 application. I want to set the connection string dynamically based on the environment, but I'm running into a question where it defaults to the connection string defined in `appsettings.json` instead of using the one I provide at runtime. I tried setting the connection string in the `Startup.cs` file like this: ```csharp public void ConfigureServices(IServiceCollection services) { var connectionString = Environment.GetEnvironmentVariable("MY_CUSTOM_CONNECTION_STRING"); services.AddDbContext<MyDbContext>(options => options.UseSqlServer(connectionString)); } ``` However, when I run the application, I get the following behavior: `System.InvalidOperationException: Connection string want to be null or empty.` I also checked that the environment variable is set correctly and can be accessed using `Environment.GetEnvironmentVariable`. To troubleshoot, I added logging to see what value is being retrieved for the connection string: ```csharp var connectionString = Environment.GetEnvironmentVariable("MY_CUSTOM_CONNECTION_STRING"); Console.WriteLine(connectionString); ``` But it shows as `null` when I debug. I also tried using `IConfiguration` to pull the connection string from `appsettings.json`, and it works fine, but I need the runtime configuration to override it. Am I missing something in my setup, or is there a different way to ensure the environment variable is used effectively?