如何从ASP.NET Core2.1读取IIS中提供的连接字符串？

{
  "ConnectionStrings": {
    "MyConnectionString": ""
  }
}

public void ConfigureServices(IServiceCollection services)
{
    // 其他配置代码...

    // 读取连接字符串配置
    var connectionString = Configuration.GetConnectionString("MyConnectionString");

    // 注册连接字符串到依赖注入容器
    services.AddSingleton(connectionString);

    // 其他配置代码...
}

public class MyController : Controller
{
    private readonly string _connectionString;

    public MyController(string connectionString)
    {
        _connectionString = connectionString;
    }

    // 其他代码...
}