Strongly Typed Configuration in a DotNet Core EXE

AppSettings.cs

class AppSettings
{
    private IConfigurationRoot _configuration;

    public AppSettings()
    {
        // Build the config with support for reload on change
        _configuration = new ConfigurationBuilder()
            .SetBasePath(Directory.GetCurrentDirectory())
            .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
            .AddEnvironmentVariables()
            .Build();

        // Register for change notifications 
        IChangeToken token = _configuration.GetReloadToken();
        token.RegisterChangeCallback(OnAppSettingsChanged, null);
        _configuration.Bind(this);
    }

    // Handle config changes by reloading data
    private void OnAppSettingsChanged(object _)
    {
        IChangeToken token = _configuration.GetReloadToken();
        token.RegisterChangeCallback(OnAppSettingsChanged, null);
        _configuration.Bind(this);
    }

    // DataConnection section of appsettings.json
    public DataConnectionSettings? DataConnection { get; set; }
    
    // BlobConnection section of appsettings.json
    public BlobConnectionSettings? BlobConnection { get; set; }
}

appsettings.json

{
    "DataConnection": {
        "DataServiceUrl": "https://aserver.somewhere.com",
        "MaxConnections": 10
    },

    "BlobConnection": {
        "Endpoint": "mystorageaccount",
        "Container": "mycontainer"
    }
}

BlobConnectionSettings.cs

// For the BlobConnection sectino of appsettings.json

class BlobConnectionSettings
{
    public string EndPoint { get; set; } = string.Empty;
    public string Container { get; set; } = string.Empty;
}

DataConnectionSettings.cs

// For the DataConnection section of appsettings.json 
class DataConnectionSettings
{
    public string DataServiceUrl { get; set; } = string.Empty;
    public int MaxConnections { get; set; } = 0;
}