一:了解asp.net core 中的几大部件
1. 从本质上来看, asp.net core 也就是 console程序台程序,所以花了很大的篇幅去介绍console程序。
(WebHost,Startup,launchSettings,wwwroot)
二:WebHost
WebHost => Socket实现的web服务的加强版。。
1. WebHost使用了建造者模式。
2. CreateDefaultBuilder 到底干了什么?
<1> 添加web服务器 支持IIS 和 Kestrel
<2> 添加configuration配置系统
支持 appsettings.json && 多环境的 appsettings.env.json
支持 commandline
<3> 添加日志系统
支持输出到Console和Debug窗口。
//IL_000d: Unknown result type (might be due to invalid IL or missing references)
//IL_0017: Expected O, but got Unknown
return WebHostBuilderExtensions.UseDefaultServiceProvider(WebHostBuilderIISExtensions.UseIISIntegration(WebHostBuilderExtensions.ConfigureLogging(WebHostBuilderKestrelExtensions.UseKestrel((IWebHostBuilder)new WebHostBuilder()).UseContentRoot(Directory.GetCurrentDirectory()).ConfigureAppConfiguration(delegate(WebHostBuilderContext hostingContext, IConfigurationBuilder config)
{
IHostingEnvironment hostingEnvironment = hostingContext.HostingEnvironment;
JsonConfigurationExtensions.AddJsonFile(JsonConfigurationExtensions.AddJsonFile(config, "appsettings.json", true, true), $"appsettings.{hostingEnvironment.EnvironmentName}.json", true, true);
if (hostingEnvironment.IsDevelopment())
{
Assembly assembly = Assembly.Load(new AssemblyName(hostingEnvironment.ApplicationName));
if (assembly != null)
{
UserSecretsConfigurationExtensions.AddUserSecrets(config, assembly, true);
}
}
EnvironmentVariablesExtensions.AddEnvironmentVariables(config);
if (args != null)
{
CommandLineConfigurationExtensions.AddCommandLine(config, args);
}
}), (Action<WebHostBuilderContext, ILoggingBuilder>)delegate(WebHostBuilderContext hostingContext, ILoggingBuilder logging)
{
LoggingBuilderExtensions.AddConfiguration(logging, hostingContext.Configuration.GetSection("Logging"));
ConsoleLoggerExtensions.AddConsole(logging);
DebugLoggerFactoryExtensions.AddDebug(logging);
})), (Action<WebHostBuilderContext, ServiceProviderOptions>)delegate(WebHostBuilderContext context, ServiceProviderOptions options)
{
options.set_ValidateScopes(context.HostingEnvironment.IsDevelopment());
});
在Build方法中做了所有的初始化操作
《1》 初始化了一个IOC容器
《2》初始化到了WebHost
《3》Startup 已单例的方式添加到了IOC容器
我们也可以继承 IStartup 。。。
总结:WebHost在启动之前做了无数的事情。。。
三:Startup
1. ConfigureServices
给程序员添加一些服务的代码区。
比如AddMvc查看mvc源码
internal static void AddViewServices(IServiceCollection services)
{
DataProtectionServiceCollectionExtensions.AddDataProtection(services);
AntiforgeryServiceCollectionExtensions.AddAntiforgery(services);
EncoderServiceCollectionExtensions.AddWebEncoders(services);
ServiceCollectionDescriptorExtensions.TryAddEnumerable(services, ServiceDescriptor.Transient<IConfigureOptions<MvcViewOptions>, MvcViewOptionsSetup>());
ServiceCollectionDescriptorExtensions.TryAddEnumerable(services, ServiceDescriptor.Transient<IPostConfigureOptions<MvcViewOptions>, MvcViewOptionsConfigureCompatibilityOptions>());
ServiceCollectionDescriptorExtensions.TryAddEnumerable(services, ServiceDescriptor.Transient<IConfigureOptions<MvcOptions>, TempDataMvcOptionsSetup>());
ServiceCollectionDescriptorExtensions.TryAddSingleton<ICompositeViewEngine, CompositeViewEngine>(services);
ServiceCollectionDescriptorExtensions.TryAddSingleton<IActionResultExecutor<ViewResult>, ViewResultExecutor>(services);
ServiceCollectionDescriptorExtensions.TryAddSingleton<IActionResultExecutor<PartialViewResult>, PartialViewResultExecutor>(services);
ServiceCollectionDescriptorExtensions.TryAddEnumerable(services, ServiceDescriptor.Transient<IControllerPropertyActivator, ViewDataDictionaryControllerPropertyActivator>());
ServiceCollectionDescriptorExtensions.TryAddTransient<IHtmlHelper, HtmlHelper>(services);
ServiceCollectionDescriptorExtensions.TryAddTransient(services, typeof(IHtmlHelper<>), typeof(HtmlHelper<>));
ServiceCollectionDescriptorExtensions.TryAddSingleton<IHtmlGenerator, DefaultHtmlGenerator>(services);
ServiceCollectionDescriptorExtensions.TryAddSingleton<ExpressionTextCache>(services);
ServiceCollectionDescriptorExtensions.TryAddSingleton<IModelExpressionProvider, ModelExpressionProvider>(services);
ServiceCollectionDescriptorExtensions.TryAddSingleton<ValidationHtmlAttributeProvider, DefaultValidationHtmlAttributeProvider>(services);
ServiceCollectionDescriptorExtensions.TryAddSingleton<IJsonHelper, JsonHelper>(services);
ServiceCollectionDescriptorExtensions.TryAdd(services, ServiceDescriptor.Singleton<JsonOutputFormatter>(delegate (IServiceProvider serviceProvider) {
return new JsonOutputFormatter(ServiceProviderServiceExtensions.GetRequiredService<IOptions<MvcJsonOptions>>(serviceProvider).get_Value().get_SerializerSettings(), ServiceProviderServiceExtensions.GetRequiredService<ArrayPool<char>>(serviceProvider));
}));
ServiceCollectionDescriptorExtensions.TryAddSingleton<IViewComponentSelector, DefaultViewComponentSelector>(services);
ServiceCollectionDescriptorExtensions.TryAddSingleton<IViewComponentFactory, DefaultViewComponentFactory>(services);
ServiceCollectionDescriptorExtensions.TryAddSingleton<IViewComponentActivator, DefaultViewComponentActivator>(services);
ServiceCollectionDescriptorExtensions.TryAddSingleton<IViewComponentDescriptorCollectionProvider, DefaultViewComponentDescriptorCollectionProvider>(services);
ServiceCollectionDescriptorExtensions.TryAddSingleton<IActionResultExecutor<ViewComponentResult>, ViewComponentResultExecutor>(services);
ServiceCollectionDescriptorExtensions.TryAddSingleton<ViewComponentInvokerCache>(services);
ServiceCollectionDescriptorExtensions.TryAddTransient<IViewComponentDescriptorProvider, DefaultViewComponentDescriptorProvider>(services);
ServiceCollectionDescriptorExtensions.TryAddSingleton<IViewComponentInvokerFactory, DefaultViewComponentInvokerFactory>(services);
ServiceCollectionDescriptorExtensions.TryAddTransient<IViewComponentHelper, DefaultViewComponentHelper>(services);
ServiceCollectionDescriptorExtensions.TryAddEnumerable(services, ServiceDescriptor.Transient<IApplicationModelProvider, TempDataApplicationModelProvider>());
ServiceCollectionDescriptorExtensions.TryAddEnumerable(services, ServiceDescriptor.Transient<IApplicationModelProvider, ViewDataAttributeApplicationModelProvider>());
ServiceCollectionDescriptorExtensions.TryAddSingleton<SaveTempDataFilter>(services);
ServiceCollectionDescriptorExtensions.TryAddTransient<ControllerSaveTempDataPropertyFilter>(services);
ServiceCollectionDescriptorExtensions.TryAddSingleton<ITempDataProvider, CookieTempDataProvider>(services);
ServiceCollectionDescriptorExtensions.TryAddSingleton<ValidateAntiforgeryTokenAuthorizationFilter>(services);
ServiceCollectionDescriptorExtensions.TryAddSingleton<AutoValidateAntiforgeryTokenAuthorizationFilter>(services);
ServiceCollectionDescriptorExtensions.TryAddSingleton<ITempDataDictionaryFactory, TempDataDictionaryFactory>(services);
ServiceCollectionDescriptorExtensions.TryAddSingleton<ArrayPool<ViewBufferValue>>(services, ArrayPool<ViewBufferValue>.get_Shared());
ServiceCollectionDescriptorExtensions.TryAddScoped<IViewBufferScope, MemoryPoolViewBufferScope>(services);
}
MVC大概注册了100多的服务。。。
2. Configure
<1> 这个方法用于在初始化的时候,将所有的中间件添加到 IApplicationBuilder 的componets数组中。
在Request请求发起的时候,按照添加顺序执行一次中间件,具体的我们下一节课说。
。。。。。。 这个方法配置的东西,只会在Request请求的过程中被调用 。。。。。。
<2> 这个方法的参数是不固定的,只要容器里面有,都可以实现依赖注入。。比如ILoggerFactory logger
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
else
{
app.UseExceptionHandler("/Home/Error");
}
环境的不同,程序的行为也不一样。。
四: launchSettings.json 启动文件
解决问题:快速的做环境切换,方便调试和开发。
目的:让你的程序在多环境一样保持稳定。
1. 直接修改文件。
2. 使用vs面板。
五:wwwroot
用来存放静态资源。