What's the best method to access configuration in .NET 6?

Question

The second answer of this question: ASP.NET Core 6 how to access Configuration during startup mentioned that we can access configuration in this way:

A nice feature worth considering it to create a class that represents your settings and then bind the configuration to an instance of that class type. For example, let's assume you create a new class called MyAppSettings with the same structure as your appSettings.json, you can do the following:

var myAppSettings = builder.Configuration.Get<MyAppSettings>();
string logLevel = myAppSettings.Logging.LogLevel.Default;

I am confused about it and I want to know how to do that and what are the benefits of this.

What's more, the best method to access configuration in .NET 6?

---

Explain my question in more detail. The appSetting.json file in my project has only one layer like this:

{
 "name": "jack",
 ...1000+,
 "age": "100"
}

So I cannot configure it using builder.congiguration.GetSection():

builder.Services.Configure<XXX>(builder.Configuration.GetSection("XXX"));

How to configure it at once without changing the structure of appSettings.json?

thank you again~

Answer 1

You can refer to this simple demo to learn about how to

create a class that represents your settings and then bind the configuration to an instance of that class type

The values in appsetting.json :

"UserCred": {
      "Username":"Jack",
      "Password":"123"
},

Create a model class:

public class User
{
    public string Username { get; set; }
    public string Password { get; set; }
}

Configure in your programs.cs :

builder.Services.Configure<User>(builder.Configuration.GetSection("UserCred"));

In the controller, use DI to inject it, then you can get the model with value:

public class HomeController : Controller
{
    private readonly IOptions<User> _configuration;

    public HomeController(IOptions<User> configuration)
    {
        _configuration = configuration;
    }

    //.......
}

What's the benefit?

For me, if there are many data ​​in appsetting.json , Creating a class to map them only needs to map once, You don't need to get them one by one, which makes coding more convenient.