任務22:課程
-
1.HTTP 處理過程
-
2.WebHost 的配置與啓動
-
3.Middleware 與管道
-
4.Routing MiddleWare 介紹
任務23:Http請求的處理過程
任務24:WebHost的配置
-
1.覆蓋配置文件
-
2.更改啓動URL
-
3.IHostingEnvironment
-
4.IApplicationLifetime
-
5.dotnet watch run
dotnet new web
settings.json
{
"ConnectionStrings":{
"DefaultConnection":"Server=...;Database=...;"
}
}
Program.cs
public static IWebHostBuilder CreateWebHostBuilder(string[] args) =>
WebHost.CreateDefaultBuilder(args)
.ConfigureAppConfiguration(configureDelegate=>{
configureDelegate.AddJsonFile("settings.json");
})
.UseStartup<Startup>();
Startup.cs
using Microsoft.Extensions.Configuration;
public void Configure(IApplicationBuilder app, IHostingEnvironment env, IConfiguration configuration)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
app.Run(async (context) =>
{
// await context.Response.WriteAsync("Hello World!");
// JsonFile
await context.Response.WriteAsync(configuration["ConnectionStrings:DefaultConnection"]);
});
}
啓動HelloCore,輸出結果
Program.cs
public static IWebHostBuilder CreateWebHostBuilder(string[] args) =>
WebHost.CreateDefaultBuilder(args)
.ConfigureAppConfiguration(configureDelegate => {
//configureDelegate.AddJsonFile("settings.json");
configureDelegate.AddCommandLine(args);
})
//.UseUrls("http://localhost:5001")
.UseStartup<Startup>();
Startup.cs
app.Run(async (context) =>
{
// await context.Response.WriteAsync("Hello World!");
// JsonFile
//await context.Response.WriteAsync(configuration["ConnectionStrings:DefaultConnection"]);
// CommandLine
await context.Response.WriteAsync($"name={configuration["name"]}");
});
設置應用程序參數
啓動HelloCore,輸出結果
任務25:IHostEnvironment和 IApplicationLifetime介紹
Startup.cs
app.Run(async (context) =>
{
await context.Response.WriteAsync($"ContentRootPath = {env.ContentRootPath}");
await context.Response.WriteAsync($"EnvironmentName = {env.EnvironmentName}");
await context.Response.WriteAsync($"WebRootPath = {env.WebRootPath}");
});
啓動HelloCore,輸出結果
Startup.cs
public void Configure(IApplicationBuilder app, IHostingEnvironment env, IConfiguration configuration, IApplicationLifetime applicationLifetime)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
applicationLifetime.ApplicationStarted.Register(() =>
{
Console.WriteLine("Started");
});
applicationLifetime.ApplicationStopped.Register(() =>
{
Console.WriteLine("Stopped");
});
applicationLifetime.ApplicationStopped.Register(() =>
{
Console.WriteLine("Stopped");
});
app.Run(async (context) =>
{
await context.Response.WriteAsync($"ContentRootPath = {env.ContentRootPath}");
await context.Response.WriteAsync($"EnvironmentName = {env.EnvironmentName}");
await context.Response.WriteAsync($"WebRootPath = {env.WebRootPath}");
});
}
啓動HelloCore,輸出結果
我心中的ASP.NET Core 新核心對象WebHost(一):
http://www.jessetalk.cn/2017/11/11/aspnet-core-object-webhost/#comment-194
我心中的ASP.NET Core 新核心對象WebHost(二):
http://www.jessetalk.cn/2017/11/14/aspnet-core-object-webhost-build/
任務26:dotnet watch run 和attach到進程調試
New Terminal
dotnet new web --name HelloCore
F5 Start Debug
在csproj 的 ItemGroup 添加引用
<DotNetCliToolReference Include="Microsoft.DotNet.Watcher.Tools" Version="2.0.0" />
New Terminal
dotnet restore
dotnet watch run
修改代碼保存後會自動重啓
瀏覽器刷新即可看到更新結果
attach到進程調試
任務27:Middleware管道介紹
-
1.Middleware 與管道的概念
-
2.用 Middleware 來組成管道實踐
-
3.管道的實現機制(RequestDelegate 與 ApplicationBuilder)
startup.cs
public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
// 添加一箇中間件,傳一個名字爲next的request delegate
app.Use(async (context,next)=>{
await context.Response.WriteAsync("1: before start...");
await next.Invoke();
});
// 接收一個RequestDelegate,返回一個RequestDelegate
app.Use(next=>{
return (context)=>{
context.Response.WriteAsync("2: in the middle of start..");
return next(context);
};
});
app.Run(async (context) =>
{
await context.Response.WriteAsync("3: start...");
});
}
啓動項目,輸出結果
// 如果不調用next,則管道終止,不會輸出"3: start..."
app.Use(next=>{
return (context)=>{
return context.Response.WriteAsync("2: in the middle of start..");
//return next(context);
};
});
// 使用Map構建路由,通過localhost:5000/task訪問
app.Map("/task", taskApp=>{
taskApp.Run(async context=>{
await context.Response.WriteAsync("this is a task");
});
});
// 添加一箇中間件,傳一個名字爲next的request delegate
app.Use(async (context,next)=>{
await context.Response.WriteAsync("1: before start...");
await next.Invoke();
});
// 接收一個RequestDelegate,返回一個RequestDelegate
// 如果不調用next,則管道終止,不會輸出"3: start..."
app.Use(next=>{
return (context)=>{
context.Response.WriteAsync("2: in the middle of start..");
return next(context);
};
});
app.Run(async (context) =>
{
await context.Response.WriteAsync("3: start...");
});
訪問 https://localhost:5001/task
任務28:RequestDelegate管道實現思路
-
1.RequestDelegate
-
2.ApplicationBuilder:多個RequestDelegate拼接
// 添加一箇中間件,傳一個名字爲next的RequestDelegate
app.Use(async (context,next)=>{
await context.Response.WriteAsync("1: before start...");// 完成自己處理
await next.Invoke();// 調用下一步
});
// 封裝一個function交給ApplicationBuilder處理
app.Use(next=>{
return (context)=>{
context.Response.WriteAsync("2: in the middle of start..");
return next(context);
};
});
任務29:自己動手構建RequestDelegate管道
新建一個控制檯程序
dotnet new console --name MyPipeline
新建一個類RequestDelegate.cs
using System;
using System.Threading.Tasks;
namespace MyPipeline
{
public delegate Task RequestDelegate(Context context);
}
新建一個類Context.cs
using System;
using System.Threading.Tasks;
namespace MyPipeline
{
public class Context
{
}
}
using System;
using System.Collections.Generic;
using System.Threading.Tasks;
namespace MyPipeline
{
class Program
{
public static List<Func<RequestDelegate,RequestDelegate>>
_list = new List<Func<RequestDelegate, RequestDelegate>>();
static void Main(string[] args)
{
Use(next=>{
return context=>{
Console.WriteLine("1");
return next.Invoke(context);
};
});
Use(next=>{
return context=>{
Console.WriteLine("2");
return next.Invoke(context);
};
});
RequestDelegate end = (Context)=>{
Console.WriteLine("end...");
return Task.CompletedTask;
};
_list.Reverse();
foreach(var middleware in _list)
{
end = middleware.Invoke(end);
}
end.Invoke(new Context());
Console.ReadLine();
}
public static void Use(Func<RequestDelegate,RequestDelegate> middleware)
{
_list.Add(middleware);
}
}
}
在任何一個Middleware可以結束管道
Use(next=>{
return context=>{
Console.WriteLine("1");
//return next.Invoke(context);
return Task.CompletedTask;// 結束管道調用,只輸出1
};
});
任務30:RoutingMiddleware介紹以及MVC引入
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Routing;
using Microsoft.Extensions.DependencyInjection;
namespace HelloCore
{
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 https://go.microsoft.com/fwlink/?LinkID=398940
public void ConfigureServices(IServiceCollection services)
{
services.AddRouting();// 添加依賴注入配置
}
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
// 通過localhost:5000/action訪問
app.UseRouter(builder=>builder.MapGet("action", async context=>{
await context.Response.WriteAsync("this is a action");
}));
// 使用Map構建路由,通過localhost:5000/task訪問
app.Map("/task", taskApp=>{
taskApp.Run(async context=>{
await context.Response.WriteAsync("this is a task");
});
});
// 添加一箇中間件,傳一個名字爲next的request delegate
app.Use(async (context,next)=>{
await context.Response.WriteAsync("1: before start...");
await next.Invoke();
});
// 如果不調用next,則管道終止,不會輸出"3: start..."
app.Use(next=>{
return (context)=>{
return context.Response.WriteAsync("2: in the middle of start..");
//return next(context);
};
});
app.Run(async (context) =>
{
await context.Response.WriteAsync("3: start...");
});
}
}
}
訪問 https://localhost:5001/action
使用UseRouter方法2
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Routing;
using Microsoft.Extensions.DependencyInjection;
namespace HelloCore
{
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 https://go.microsoft.com/fwlink/?LinkID=398940
public void ConfigureServices(IServiceCollection services)
{
services.AddRouting();// 添加依賴注入配置
}
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
// 使用UseRouter方法2
// 通過localhost:5000/action訪問
RequestDelegate handler = context=>context.Response.WriteAsync("this is a action");
var route = new Route(
new RouteHandler(handler),
"action",
app.ApplicationServices.GetRequiredService<IInlineConstraintResolver>()
);
app.UseRouter(route);
// 使用UseRouter方法1
// 通過localhost:5000/action訪問
app.UseRouter(builder=>builder.MapGet("action", async context=>{
await context.Response.WriteAsync("this is a action");
}));
// 使用Map構建路由,通過localhost:5000/task訪問
app.Map("/task", taskApp=>{
taskApp.Run(async context=>{
await context.Response.WriteAsync("this is a task");
});
});
// 添加一箇中間件,傳一個名字爲next的request delegate
app.Use(async (context,next)=>{
await context.Response.WriteAsync("1: before start...");
await next.Invoke();
});
// 如果不調用next,則管道終止,不會輸出"3: start..."
app.Use(next=>{
return (context)=>{
return context.Response.WriteAsync("2: in the middle of start..");
//return next(context);
};
});
app.Run(async (context) =>
{
await context.Response.WriteAsync("3: start...");
});
}
}
}
訪問 https://localhost:5001/action
RountingMiddleware介紹
var routeHandler = new RouteHandler(context=>context.Response.WriteAsync("test"));
var route = new Route(routeHandler);
new RouteMiddleware(route)
RouteMiddleware.Invoke(httpContext)
_route.RouteAsync(context)
routeMatch(RouteContext)
OnRouteMatched(RouteContext)