标签：read dha star pre stat readonly string let color
比起 Angular 的依赖注入, core 的相对简单许多, 容易明白
所有 provider 都在 startup 里配置.
public void ConfigureServices(IServiceCollection services) { services.Configure<Business>(Configuration.GetSection("business")); services.Configure<Configuration.Email>(Configuration.GetSection("email")); services.AddEmail(); // Razor template services.AddSingleton<ICompositeViewEngine, CompositeViewEngine>(); services.AddSingleton<IActionContextAccessor, ActionContextAccessor>(); // Entity services.AddScoped(_ => new DB(Configuration.GetConnectionString("DefaultConnection"))); // hangfire services.AddHangfire(config => config.UseSqlServerStorage(Configuration.GetConnectionString("DefaultConnection"))); // MVC services.Configure<RazorViewEngineOptions>(options => { options.ViewLocationExpanders.Add(new FeatureLocationExpander()); }); services.AddMvc(); }
controller 就通过 constructor 来注入就可以了.
private readonly DB db; private ICompositeViewEngine CompositeViewEngine { get; set; } private ActionContext ActionContext { get; set; } private IServiceProvider ServiceProvider { get; set; } private ITempDataProvider TempDataProvider { get; set; } private Configuration.Email EmailConfig { get; set; } public DebugController( DB db, ICompositeViewEngine compositeViewEngine, IActionContextAccessor actionContextAccessor, IServiceProvider serviceProvider, ITempDataProvider tempDataProvider, IOptionsSnapshot<Configuration.Email> emailOptionsAccessor ) { CompositeViewEngine = compositeViewEngine; ActionContext = actionContextAccessor.ActionContext; ServiceProvider = serviceProvider; TempDataProvider = tempDataProvider; EmailConfig = emailOptionsAccessor.Value; this.db = db; }
provider 有 3 个级别
AddSingleton
AddScoped
AddTransient
单列是说整个 App 用一个实例
Scope 一个 request 一个实例
transient 则是每一个注入一个实例
一个模块一般上会提供好多 Service
那么要让 startup 干净一些的话，我们可以包装起来
就好像这样 services.AddEmail();
做法是开一个扩展方法
namespace Project.Email { public static class ServiceCollectionExtensions { public static IServiceCollection AddEmail( this IServiceCollection services) { services.AddSingleton<ICompositeViewEngine, CompositeViewEngine>(); services.AddSingleton<IActionContextAccessor, ActionContextAccessor>(); services.AddScoped<EmailService, EmailService>(); return services; } } public class EmailService { public EmailService() { } public string name { get; set; } = "dada"; } }
标签：read dha star pre stat readonly string let color
原文地址：http://www.cnblogs.com/keatkeat/p/7742543.html
