.NET Core 控制台程序没有 ASP.NET Core 的 IWebHostBuilder 与 Startup.cs ，那要读 appsettings.json、注依赖、配日志、设 IOptions 该怎么办呢？因为这些操作与 ASP.NET Core 无依赖，所以可以自己动手，轻松搞定。

1、读 appsettings.json ，ConfigurationBuilder 上

varconf = newConfigurationBuilder() .SetBasePath(Directory.GetCurrentDirectory()) .AddJsonFile("appsettings.json", true, true) .AddJsonFile("appsettings.Development.json", true, true) .Build();

需要安装 nuget 包 Microsoft.Extensions.Configuration 、Microsoft.Extensions.Configuration.FileExtensions 、Microsoft.Extensions.Configuration.Json

2、注依赖，IServiceCollection + IServiceProvider 一起来

IServiceCollection services = newServiceCollection();//...services.AddSingleton<CosClient> ();IServiceProvider serviceProvider = services.BuildServiceProvider();varcosClient = serviceProvider.GetService<CosClient>();

需要安装 nuget 包 Microsoft.Extensions.DependencyInjection

3、配日志， AddLogging 与 ILoggingBuilder 肩并肩

services.AddLogging(builder => builder .AddConfiguration(conf.GetSection("Logging")) .AddConsole());

需要安装 nuget 包 Microsoft.Extensions.Logging 、Microsoft.Extensions.Logging.Configuration 、Microsoft.Extensions.Logging.Console

4、设IOptions，AddOptions() 与 Configure<T> 齐步走

services.AddOptions();services.Configure<CosClientOptions>(conf.GetSection( "cosClient"));

需要安装 nuget 包 Microsoft.Extensions.Options 与 Microsoft.Extensions.Options.ConfigurationExtensions

完整代码：

classProgram{

staticasyncTask Main( string[] args) { varconf = newConfigurationBuilder() .SetBasePath(Directory.GetCurrentDirectory()) .AddJsonFile("appsettings.json", true, true) .AddJsonFile("appsettings.Development.json", true, true) .Build(); IServiceCollection services = newServiceCollection(); services.AddLogging(builder => builder .AddConfiguration(conf.GetSection("Logging")) .AddConsole()); services.AddOptions(); services.Configure<CosClientOptions>(conf.GetSection( "cosClient")); services.AddSingleton<CosClient> (); IServiceProvider serviceProvider = services.BuildServiceProvider();

varcosClient = serviceProvider.GetService<CosClient> (); }}