请问关于c的具体应用场景有哪些？

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我在ASP.NET核心上经历了+configuration+文档。文档说明您可以从应用程序的任何位置访问配置。下面是模板创建的Startup.cs内容：

csharppublic class Startup{ public Startup(IHostingEnvironment env) { var builder=new C

我在ASP.NET核心上经历了 configuration documentation.文档说您可以从应用程序的任何位置访问配置.

下面是模板创建的Startup.cs

public class Startup { 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); if (env.IsEnvironment("Development")) { // This will push telemetry data through Application Insights pipeline faster, allowing you to view results immediately. builder.AddApplicationInsightsSettings(developerMode: true); } builder.AddEnvironmentVariables(); Configuration = builder.Build(); } public IConfigurationRoot Configuration { get; } // This method gets called by the runtime. Use this method to add services to the container public void ConfigureServices(IServiceCollection services) { // Add framework services. services.AddApplicationInsightsTelemetry(Configuration); services.AddMvc(); } // This method gets called by the runtime. Use this method to configure the HTTP request pipeline public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory) { loggerFactory.AddConsole(Configuration.GetSection("Logging")); loggerFactory.AddDebug(); app.UseApplicationInsightsRequestTelemetry(); app.UseApplicationInsightsExceptionTelemetry(); app.UseMvc(); } }

所以在Startup.cs中我们配置了所有设置,Startup.cs也有一个名为Configuration的属性

我无法理解您如何在控制器或应用程序中的任何位置访问此配置？ MS建议使用options pattern,但我只有4-5个键值对,所以我不想使用选项模式.我只想访问应用程序中的Configuration.如何在任何课程中注入它？

更新

使用ASP.NET Core 2.0将automatically在依赖注入容器中添加应用程序的IConfiguration实例.这也与WebHostBuilder上的ConfigureAppConfiguration结合使用.

例如：

public static void Main(string[] args) { var host = WebHost.CreateDefaultBuilder(args) .ConfigureAppConfiguration(builder => { builder.AddIniFile("foo.ini"); }) .UseStartup<Startup>() .Build(); host.Run(); }

就像在ConfigurationServices中将IConfiguration实例作为单个对象添加到服务集合一样简单：

public void ConfigureServices(IServiceCollection services) { services.AddSingleton<IConfiguration>(Configuration); // ... }

Configuration是Startup类中的实例.

这允许您在任何控制器或服务中注入IConfiguration：

public class HomeController { public HomeController(IConfiguration configuration) { // Use IConfiguration instance } }