.net core 2.0 mvc 初步学习

mvc_study

StudyStartup

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using Web.Study.ConfigModel;
using Web.Study.MonsterInterface;

namespace Web.Study.InhertStartup
{
    public class StudyStartup
    {

        protected IConfiguration Configuration { get; set; }

        public StudyStartup()
        {

        }

        /// <summary>
        /// 用于获取配置信息
        /// </summary>
        /// <param name="configuration"></param>
        public StudyStartup(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public IServiceProvider ConfigureServices(IServiceCollection services)
        {

            //注入mvc
            services.AddMvc();

            //添加Options
            services.AddOptions();

            //获取配置信息
            services.Configure<AppSetting>(Configuration.GetSection(nameof(AppSetting)));

            //开启Session功能
            services.AddSession(options ={
                options.IdleTimeout = TimeSpan.FromMinutes(30);
            });

            //构建一个默认的serviceProvider处理对象
            return services.BuildServiceProvider();
        }

        public void Configure(IApplicationBuilder app,
            IHostingEnvironment environment,
            ILoggerFactory loggerFactory,
            IHttpContextFactory httpContextFactory,
            DiagnosticSource diagnosticSource,
            DiagnosticListener diagnosticListener)
        {
            //当前环境为开发环境
            if (environment.IsDevelopment())
            {
                app.UseBrowserLink();
                app.UseDeveloperExceptionPage();
            }
            else
            {
                app.UseExceptionHandler("/Home/Error");
            }

            // 重要: session的注册必须在UseMvc之前，因为MVC里面要用 
            app.UseSession();

            //使用webroot中的静态文件
            app.UseStaticFiles();

            app.UseMvc(routes =>
            {
                routes.MapRoute(
                    name: "default",
                    template: "{controller=Home}/{action=Index}/{id?}");
            });
        }
    }
}

Program

    public static IWebHost BuildWebHost<T>(string[] args) where T:class 
    {
        IWebHostBuilder webHostBuilder = WebHost.CreateDefaultBuilder(args);

        IWebHostBuilder hostBuilder = webHostBuilder.UseStartup<T>();

        IWebHost webHost = hostBuilder.Build();

        return webHost;

    }

---

code explain

construction

public StudyStartup(IConfiguration configuration)

相关源码
IWebHostBuilder webHostBuilder = WebHost.CreateDefaultBuilder(args);

方法解析

public static IWebHostBuilder CreateDefaultBuilder(string[] args)
{
  return new WebHostBuilder()
      .UseKestrel()//Specify Kestrel as the server to be used by the web host.
      .UseContentRoot(Directory.GetCurrentDirectory())//采用当前目录作为内容跟目录
      //配置信息处理
      .ConfigureAppConfiguration((Action<WebHostBuilderContext, IConfigurationBuilder>) ((hostingContext, config) =>
      {
             //注入运行环境
            IHostingEnvironment hostingEnvironment = hostingContext.HostingEnvironment;
              //加载配置文件
            config.AddJsonFile("appsettings.json", true, true).AddJsonFile(string.Format("appsettings.{0}.json", (object) hostingEnvironment.EnvironmentName), true, true);
          //根据运行环境加载相应文件
            if (hostingEnvironment.IsDevelopment())
            {
              Assembly assembly = Assembly.Load(new AssemblyName(hostingEnvironment.ApplicationName));
              if (assembly != (Assembly) null)
                config.AddUserSecrets(assembly, true);
            }

            config.AddEnvironmentVariables();
            if (args == null)
              return;
            config.AddCommandLine(args);
      }))
      //配置日志信息
      .ConfigureLogging((Action<WebHostBuilderContext, ILoggingBuilder>) ((hostingContext, logging) =>
      {
        logging.AddConfiguration((IConfiguration) hostingContext.Configuration.GetSection("Logging"));
        logging.AddConsole();
        logging.AddDebug();
      }))
      .UseIISIntegration()//采用IIS进行发布
      .UseDefaultServiceProvider((Action<WebHostBuilderContext, ServiceProviderOptions>) ((context, options) => options.ValidateScopes = context.HostingEnvironment.IsDevelopment()));//采用默认的处理机制
}

即若需要使用startup的有参构造，则需要在configureappconfiguration中进行配置相应处理类

请求走向:

初始:Run --> ConfigureServices --> Configure

配置信息的获取:

<Controller>

protected AppSetting ConfigInfo { get; set; }

    //读取配置信息
protected BaseController(IOptions<AppSetting> options) => ConfigInfo = options.Value;

DI注入

1.创建的DI注入在ConfigureServices进行处理

注入方式：

services.AddSingleton(u => new MonsterDIController(new GuestDal()));//指定控制器进行注入

services.AddSingleton<IDal,DefaultDal>();//统一注入  全局共享一个

services.AddTransient<IDal, DefaultDal>();//统一注入    每次使用都不一样，不同的类或不同的方法使用都不一样

services.AddScoped<IDal, EmptyDal>();//统一注入   一次请求共享一个对象

注：
    当对同一类型构造传入不同类型对象的注入时，
    不考虑注入类型或范围
    已最终注入类型为传入对象创建实例

例如:
    <Controller>

        protected IDal Dal { get; set; }

        public MonsterDIController(IDal dal)
        {
            this.Dal = dal;
        }

    <ConfigureServices>
        如上述一致

    <Result>
        最终创建实例时，会传入EmptyDal

开启Session功能：

<method --> ConfigureServices>

    services.AddSession(options => {
            options.IdleTimeout = TimeSpan.FromMinutes(30);//存储时长
        });

<method --> Configure >
    // 重要: session的注册必须在UseMvc之前，因为MVC里面要用 
        app.UseSession();