ASP.NET Core—access Configuration from static class - asp.net-core-mvc

Question

I want a simple static class that accesses the Configuration object. All the config info is already read in from the appsettings.json file in the Startup class. I just need an easy way to access it. Is this possible?
namespace MyNamespace
{
public static class Config
{
public string Username => Configuration["Username"];
public string Password => Configuration["Password"];
}
}
Anywhere else in the app:
string username = Config.Username;
string password = Config.Password;

Answer 1

A slightly shorter version based on the same principle as above...
public Startup(IConfiguration configuration)
{
Configuration = configuration;
StaticConfig = configuration;
}
public static IConfiguration StaticConfig { get; private set; }
To use in another static class:
string connString = Startup.StaticConfig.GetConnectionString("DefaultConnection");

Answer 2

create the ConfigurationHelper static class in the service layer, so it can be used in other layers without circular dependency.
public static class ConfigurationHelper
{
public static IConfiguration config;
public static void Initialize(IConfiguration Configuration)
{
config = Configuration;
}
}
initialize the ConfigurationHelper inside the ConfigureServices method in the Startup class.
ConfigurationHelper.Initialize(Configuration);
Use it wherever you want including your static classes
e.g: ConfigurationHelper.config.GetSection("AWS:Accesskey").Value;

Answer 3

After much research, this works (in ASPNetCore 2.2) for accessing the appsettings.json config from a static class but for some reason appsettings.development.json no longer loads properly but it might be something else in my project messing that up. The reloadOnChange does work. As a bonus it also has IHostingEnvironment and IHttpContextAccessor. While this works, I have recently decided to switch back to a more DI approach to follow the paradigm shift as others have mentioned.
So here is one of many ways to access some DI stuff (including the configuration) in a static class:
AppServicesHelper.cs:
public static class AppServicesHelper
{
static IServiceProvider services = null;
/// <summary>
/// Provides static access to the framework's services provider
/// </summary>
public static IServiceProvider Services
{
get { return services; }
set
{
if (services != null)
{
throw new Exception("Can't set once a value has already been set.");
}
services = value;
}
}
/// <summary>
/// Provides static access to the current HttpContext
/// </summary>
public static HttpContext HttpContext_Current
{
get
{
IHttpContextAccessor httpContextAccessor = services.GetService(typeof(IHttpContextAccessor)) as IHttpContextAccessor;
return httpContextAccessor?.HttpContext;
}
}
public static IHostingEnvironment HostingEnvironment
{
get
{
return services.GetService(typeof(IHostingEnvironment)) as IHostingEnvironment;
}
}
/// <summary>
/// Configuration settings from appsetting.json.
/// </summary>
public static MyAppSettings Config
{
get
{
//This works to get file changes.
var s = services.GetService(typeof(IOptionsMonitor<MyAppSettings>)) as IOptionsMonitor<MyAppSettings>;
MyAppSettings config = s.CurrentValue;
return config;
}
}
}
}
Startup.cs:
public Startup(IHostingEnvironment env)
{
var builder = new ConfigurationBuilder()
.SetBasePath(env.ContentRootPath)
.AddJsonFile("appsettings.json", optional: false, reloadOnChange: true)
.AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true, reloadOnChange: true)
.AddEnvironmentVariables();
Configuration = builder.Build();
}
public void ConfigureServices(IServiceCollection services)
{
//...
services.AddHttpContextAccessor();//For HttpContext.
// Register the IOptions object
services.Configure<MyAppSettings>(Configuration.GetSection(nameof(MyAppSettings)));
//Explicitly register the settings object by delegating to the IOptions object so that it can be accessed globally via AppServicesHelper.
services.AddSingleton(resolver => resolver.GetRequiredService<IOptionsMonitor<MyAppSettings>>().CurrentValue);
}
public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
//...
AppServicesHelper.Services = app.ApplicationServices;
//...
}
Controller:
public class MyController: Controller
{
public MyController()
{
}
public MyAppSettings Config => AppServicesHelper.Config;
public async Task<IActionResult> doSomething()
{
testModel tm = await myService.GetModel(Config.Setting_1);
return View(tm);
}
}
Another class library:
public static class MyLibraryClass
{
public static string GetMySetting_ => AppServicesHelper.Config.Setting_1;
public static bool IsDev => AppServicesHelper.HostingEnvironment.IsDevelopment();
}
MyAppSettings.cs is any class that maps to a MyAppSettings section in appsettings.json:
public class MyAppSettings
{
public string Setting_1 {get;set;}
}
appsettings.json:
{
"Logging": {
"LogLevel": {
"Default": "Warning"
}
},
"AllowedHosts": "*",
"MyAppSettings": {
"Setting_1": "something"
}
}

Answer 4

I've similar problems, and after reading the document from Microsoft. I've resolved it:
Create an static ApplicationSettings class
public static class ApplicationSettings
{
public const string User = "UserOptions";
public static UserOptions UserOptions { get; set; } = new UserOptions();
// other options here...
}
Create an options class
public class UserOptions
{
public string Username { get; set; };
public string Password { get; set; };
}
Init the Options class in Program.cs
ConfigurationManager configuration = builder.Configuration;
configuration.GetSection(ApplicationSettings.User).Bind(ApplicationSettings.UserOptions);
Update your appsettings.json
{
"UserOptions": {
"Username": "input_your_username_here",
"Password": "input_your_password_here"
}
}
You can call it anywhere in your project now
public void MethodA()
{
string username = ApplicationSettings.UserOptions.Username;
string password = ApplicationSettings.UserOptions.Password;
}
public static void MethodB()
{
string username = ApplicationSettings.UserOptions.Username;
string password = ApplicationSettings.UserOptions.Password;
}
Hope this could help you well.

Answer 5

I agree with mcbowes, it's in the docs, but the first example looks more like what you need...want:
public class Program
{
public static IConfigurationRoot Configuration { get; set; }
public static void Main(string[] args = null)
{
var builder = new ConfigurationBuilder()
.SetBasePath(Directory.GetCurrentDirectory())
.AddJsonFile("appsettings.json");
Configuration = builder.Build();
Console.WriteLine($"option1 = {Configuration["option1"]}");
// Edit:
IServiceCollection services = new ServiceCollection();
services.AddOptions();
services.Configure<HelloWorldOptions>(_configuration.GetSection("HelloWorld"));
// And so on...
}
}

Answer 6

Try avoid using a static class and use DI
namespace MyNamespace {
public interface IConfig {
string Username { get; }
string Password { get; }
}
public class Config : IConfig {
public Config(IConfiguration configuration) {
_configuration = configuration;
}
readonly IConfiguration _configuration;
public string Username => _configuration["Username"];
public string Password => _configuration["Password"];
}
}
The setup DI in StartUp class
public class Startup {
public void ConfigureServices(IServiceCollection services) {
//...
services.AddTransient<IConfig, Config>();
...
}
}
And use it like so
public class TestUsage {
public TestUsage(IConfig config) {
_config = config;
}
readonly IConfig _config;
public string Username => _config.Username;
public string Password => _config.Password;
}

Answer 7

You can use Signleton pattern to access your configurations from anywhere
public class ConnectionStrings
{
private ConnectionStrings()
{
}
// property with getter only will not work.
public static ConnectionStrings Instance { get; protected set; } = new ConnectionStrings();
public string DatabaseConnection { get; set; }
}
and in your startup class
public class Startup
{
private readonly IConfiguration configuration;
public Startup(IConfiguration configuration)
{
this.configuration = configuration;
configuration.GetSection("ConnectionStrings").Bind(ConnectionStrings.Instance);
}
public void ConfigureServices(IServiceCollection services)
{
}
public void Configure(IApplicationBuilder app)
{
}
}

Answer 8

This has already been said but I'm going to say it.
I believe .Net Core wants developers to get values through Dependency Inject. This is what I've noticed from my research but I am also speculating a bit. As developers, we need to follow this paradigm shift in order to use .Net Core well.
The Options Pattern is a good alternative to the static config. In your case, it'll look like this:
appsettings.json
{
"Username": "MyUsername",
"Password": "Password1234"
}
SystemUser.cs
public class SystemUser
{
public string Username { get; set; } = "";
public string Password { get; set; } = "";
}
Startup.cs
services.Configure<SystemUser>(Configuration);
And to use the SystemUser class, we do the following.
TestController.cs
public class TestController : Controller
{
private readonly SystemUser systemUser;
public TestController(IOptionsMonitor<SystemUser> systemUserOptions)
{
this.systemUser = systemUserOptions.CurrentValue;
}
public void SomeMethod()
{
var username = this.systemUser.Username; // "MyUsername"
var password = this.systemUser.Password; // "Password1234"
}
}
Even though we are not using a static class, I think this is the best alternative that fits your needs. Otherwise, you might have to use a static property inside the Startup class which is a scary solution imo.

Answer 9

Personally I like the method used in this link
Essentially it just adding a static field to your options class.
public class WeblogConfiguration
{
public static WeblogConfiguration Current;
public WeblogConfiguration()
{
Current = this;
}
}
Then in any static class you can do:
WeblogConfiguration.Current
Simple and very straight forward

Answer 10

If you are using environment variables as your configuration, you can access the environment variable directly rather than via the configuration object.
using System;
namespace My.Example
{
public static class GetPaths
{
private static readonly string MyPATH =
Environment.GetEnvironmentVariable("PATH");
private static readonly string MySpecialPath =
Environment.GetEnvironmentVariable("PREFIX_SpecialPath");
...
}
}

Answer 11

I think you could use extension function, something like this
public static string ConfigToSomeThing(this IConfiguration config, int value)
{
return config[value.ToString()] ?? "";
}
Then any place , just injection IConfiguration and use extension method
_systemConfiguration.ConfigToSomeThing(123);

Answer 12

I just created below class:
/// <summary>
///
/// </summary>
public static class ConfigurationManager
{
/// <summary>
///
/// </summary>
public sealed class ConfigurationManagerAppSettings
{
/// <summary>
///
/// </summary>
internal ConfigurationManagerAppSettings() { }
/// <summary>
///
/// </summary>
/// <param name="key"></param>
/// <returns></returns>
public string this[string key] => (TheConfiguration ?? throw new Exception("Set ConfigurationManager.TheConfiguration in Startup.cs")).GetSection($"AppSettings:{key}").Value;
}
/// <summary>
///
/// </summary>
public static IConfiguration? TheConfiguration { get; set; }
/// <summary>
///
/// </summary>
public static readonly ConfigurationManagerAppSettings AppSettings = new ConfigurationManagerAppSettings();
}
and below is my code:
public class Startup
{
public Startup(IConfiguration configuration) {
Configuration = configuration;
}
public IConfiguration Configuration { get; }
// This method gets called by the runtime. Use this method to add services to the container.
public void ConfigureServices(IServiceCollection services) {
ConfigurationManager.TheConfiguration = Configuration;

Answer 13

I've used this approach and it seems to work well. In your static class, add a public IConfiguration property.
namespace MyNamespace
{
public static class Config
{
public static IConfiguration Configuration { get; set; }
public string Username => Configuration["Username"];
public string Password => Configuration["Password"];
}
}
In Startup.cs constructor, use dependency injection to get the configuration, and then assign it to the public member of your static class.
public class Startup
{
public Startup(IConfiguration configuration)
{
MyNamespace.Config.Configuration = configuration;
}
// The rest of the startup code...
}

Answer 14

I was getting same issue and I wanted to access app setting in static class so I put this solution. Write this below code in static class in my code class name was EncryptionUtility
private static string _saltKey = string.Empty;
private static IConfiguration configuration;
public static void AppSettingsConfigure(IConfiguration _config)
{
configuration = _config;
_saltKey = Convert.ToString(configuration["Security:EncyptPassword"]);
}
Call Appsettingconfiure from the program.cs file. Here, EncryptionUtility is static class or you can only write static method as your requirement. I had put this line above app.Run();
EncryptionUtility.AppSettingsConfigure(app.Services.GetRequiredService<IConfiguration>());
appsettings.json :
{
"Security": {
"EncyptPassword": "Password"
}
}

Answer 15

Here is a way to obtain the configuration values from a NET.Core page without having to reference these statically but then still being able to pass them to other static functions called from the non-static class.
At the top of your non-static class add this:
private readonly IConfiguration _configuration;
Then in the constructor function bring in the existing configuration as input to the function:
IConfiguration configuration
Then assign the configuration to your read only variable inside the constructor function:
_configuration = configuration;
Here is an example of what it should look like:
public class IndexModel : PageModel
{
private readonly IConfiguration _configuration;
public IndexModel(IConfiguration configuration)
{
_configuration = configuration;
}
}
After this you can reference the configuration in any function in the class by referencing _configuration and can even then pass this on to other static functions that you call from other classes:
public async Task OnGetAsync()
{
AnotherClass.SomeFunction(_configuration);
}
Then in the called static class I can make use of the configuration values:
public static string SomeFunction(IConfiguration configuration)
{
string SomeValue = configuration.GetSection("SomeSectionOfConfig")["SomeValue"];
}
I have a class that calls some stored procedures for viewing and amending data and passes parameter values from appsettings.json using this approach.

Answer 16

Consider using the instructions here for ASP.NET Core Configuration.
You can create a class to store your configuration settings and then access the values, something like this:
_config.UserName
In Startup - ConfigureServices:
services.Configure<Config>(Configuration.GetSections("General"));
Then just inject your object wherever you need as:
IOptions<Config> config

Answer 17

The IConfiguration is Injectable anywhere within the Project. But in the case of static class, the option I am using and maybe only approach...
var Configuration = new ConfigurationBuilder()
.AddUserSecrets<Startup>()
.Build();
And, you can add required section, such in this code block above, I added 'UserSecrets'.