ASP.NET CORE 跨平台开发从入门到实战

第五章 CORE

5.1 CORE 介绍

5.1.1 CORE 应用

Program.cs

 public class Program
    {
        public static void Main(string[] args)
        {
            var host = new WebHostBuilder()
                .UseKestrel()
                .UseContentRoot(Directory.GetCurrentDirectory())
                .UseIISIntegration()
                .UseStartup<Startup>()
                .UseApplicationInsights()
                .Build();

            host.Run();
        }
    }

5.1.2 Startup:用来定义请求处理管道和配置应用需要的服务，该类必须是公开（public）的，而且必须含有以下两个方法。

 public class Startup
    {
        // This method gets called by the runtime. Use this method to add services to the container.
        // For more information on how to configure your application, visit 
        public void ConfigureServices(IServiceCollection services)
        {
        }

        // 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();

            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }

            app.Run(async (context) =>
            {
                await context.Response.WriteAsync("Hello World!");
            });
        }
    }

5.1.3 服务

5.1.4 中间件

5.1.5 服务器

5.1.6 内容根目录

默认情况下，内容根目录与宿主目录应用的可执行程序的应用根目录相同；其他位置可以通过WebHostBuilder来设置。

5.1.7 网站根目录

。

5.1.8 配置

5.1.9 环境

5.2 Application StartUp

5.2.1 实战中间件

• Core Web Application项目，选择空模板
  然后为项目添加一个Microsoft.Extensions.Loggin.Console
  NuGet命令执行：
  Install-Package Microsoft.Extensions.Logging.Console

  
  
• 新建一个类RequestIpMiddleware.cs

 public class RequestIpMiddleware
    {
        private readonly RequestDelegate _next;
        private readonly ILogger _logger;

        public RequestIpMiddleware(RequestDelegate next, ILoggerFactory loggetFactory)
        {
            _next = next;
            _logger = loggetFactory.CreateLogger<RequestIpMiddleware>();
        }
        public async Task Invoke(HttpContext context)
        {
            _logger.LogInformation("User Ip :" +
                context.Connection.RemoteIpAddress.ToString());
            await _next.Invoke(context);
        }
    }

• 再建一个RequestIPExtensions.cs

public static class RequestIPExtensions
    {
        public static IApplicationBuilder UseRequestIp(this IApplicationBuilder builder)
        {
            return builder.UseMiddleware<RequestIpMiddleware>();
        }
    }

这样就编写好了一个中间件（好吧，不知所以……）

• 使用中间件，在Startup.cs中添加app.UseRequestIp();