[ASP.NET Core] Configuration

 ASP.NET Core    Configuration    appsettings.json     Service Container  

▌Introduction

---

We will learn the following ways to use Configuration in ASP.NET Core project.

▋Inject to Service Container

▋Create a static config-provider

▌Environment

---

▋Visual Studio 2015 Update 3  

▋Microsoft.AspNetCore.Mvc 1.0.0

▌Implement

---

▋Default way

Here is the default way to read the contents in appsettings.json.

▋Startup.cs

public IConfigurationRoot Configuration { get; } 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)                 .AddEnvironmentVariables();     Configuration = builder.Build();     var siteName = Configuration["Config:SiteName"]; }

▋appsettings.json

{   "Config": {     "SiteName": "ASP.NET Core X Angular2",     "SiteOwner":  "2016 JB"   } }

▋Inject to Service container

Create a class to store the configuration values.

▋ConfigManager.cs

public class ConfigManager {         public string SiteName { get; set; }         public string SiteOwner { get; set; } }

▋Startup.cs

Then inject the configurations as a ConfigManager object to the Service container.

public void ConfigureServices(IServiceCollection services) {       //Skip…       services.Configure<ConfigManager>(Configuration.GetSection("Config")); }

▋Usage in MVC Controller

private ConfigManager _configManager = null;         public HomeController(IOptions<ConfigManager> options)         {             IOptions<ConfigManager> cfgMangerOptions = options;           this._configManager = cfgMangerOptions.Value;         }         public IActionResult Index()         {             ViewBag.Title = this._configManager.SiteName;             ViewBag.Owner = this._configManager.SiteOwner;             return View();         }     }

Result:

▋Create a static config-provider

Here is the other simple way to make the configurations available at any class, not just Controller. Just create a static class to store them.

▋ConfigProvider.cs

public static class ConfigProvider {         public static string SiteName { get; set; }         public static string SiteOwner { get; set; } }

▋Startup.cs

public void ConfigureServices(IServiceCollection services) {       //Skip …       var configManager = new ConfigManager();       Configuration.GetSection("Config").Bind(configManager);       ConfigProvider.SiteName = configManager.SiteName;       ConfigProvider.SiteOwner = configManager.SiteOwner; }

Notice that we could bind the configuration values recursively into a complex class with Configuration.GetSection("Config").Bind() function.

▋Usage

ViewBag.Title = ConfigProvider.SiteName; ViewBag.Owner = ConfigProvider.SiteOwner;

▋IOptionsSnapshot

Requires ASP.NET Core 1.1 or higher.

ASP.NET Core 1.1 and higher versions support reloading configuration data when the configuration file has changed. Take a look at the sample in ASP.NET Core documents.

▌Reference

---

▋ASP.NET Core documents