问如何在.net核心(不是强类型的)中拥有和访问可变数量的连接字符串？

EN

{
  "ConnectionStrings": {
    "SqlServerConnection" : "Server=.\\sql2012express;Database=aspnet-IdentityServer4WithAspNetIdentity;Trusted_Connection=True;MultipleActiveResultSets=true",
    "SqLiteConnection": "Data\\LynxJournal.db"
  },
}

_config.GetConnectionString("SqliteConnection")

    public Startup(IHostingEnvironment env)
    {
        var builder = new ConfigurationBuilder()
            .SetBasePath(env.ContentRootPath)
            .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
            .AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true);

        builder.AddEnvironmentVariables();
        Configuration = builder.Build();

        Environment = env;
    }

    public IConfigurationRoot Configuration { get; }
    private IHostingEnvironment Environment { get; }

    public void ConfigureServices(IServiceCollection services)
    {
        services.AddMemoryCache();
        services.AddEntityFrameworkSqlite().AddDbContext<LynxJournalDbContext>();


        services.AddMvcCore()
            .AddAuthorization()
            .AddJsonFormatters();


        services.AddSingleton<IConfiguration>(Configuration);
        services.AddSingleton<IHostingEnvironment>(Environment);

        Services = services;
    }