初识ASP.NET CORE
- 2020 年 3 月 31 日
- 笔记
首先创建一个asp.net core web应用程序
第二步
目前官方预置了7种模板项目供我们选择。从中我们可以看出，既有我们熟悉的MVC、WebAPI，又新添加了Razor Page，以及结合比较流行的Angular、React前端框架的模板项目。
空项目模板
Program.cs
using System; using System.Collections.Generic; using System.IO; using System.Linq; using System.Threading.Tasks; using Microsoft.AspNetCore; using Microsoft.AspNetCore.Hosting; using Microsoft.Extensions.Configuration; using Microsoft.Extensions.Logging; namespace WebApplication6 { public class Program { public static void Main(string[] args) { CreateWebHostBuilder(args).Build().Run(); } public static IWebHostBuilder CreateWebHostBuilder(string[] args) => WebHost.CreateDefaultBuilder(args) .UseStartup<Startup>(); } }
实质就是控制台应用
Startup.cs
using System; using System.Collections.Generic; using System.Linq; using System.Threading.Tasks; using Microsoft.AspNetCore.Builder; using Microsoft.AspNetCore.Hosting; using Microsoft.AspNetCore.Http; using Microsoft.AspNetCore.HttpsPolicy; using Microsoft.AspNetCore.Mvc; using Microsoft.Extensions.Configuration; using Microsoft.Extensions.DependencyInjection; namespace WebApplication6 { public class Startup { public Startup(IConfiguration configuration) { Configuration = configuration; } public IConfiguration Configuration { get; } // This method gets called by the runtime. Use this method to add services to the container. public void ConfigureServices(IServiceCollection services) { services.Configure<CookiePolicyOptions>(options => { // This lambda determines whether user consent for non-essential cookies is needed for a given request. options.CheckConsentNeeded = context => true; options.MinimumSameSitePolicy = SameSiteMode.None; }); services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1); } // 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(); } else { app.UseExceptionHandler("/Error"); app.UseHsts(); } app.UseHttpsRedirection(); app.UseStaticFiles(); app.UseCookiePolicy(); app.UseMvc(); } } }
提供最原始的HttpContext。
Web API
创建完整的HTTP服务，使用Controller处理请求，仅返回数据无视图返回
using System; using System.Collections.Generic; using System.Linq; using System.Threading.Tasks; using Microsoft.AspNetCore.Mvc; namespace WebApplication7.Controllers { [Route("api/[controller]")] [ApiController] public class ValuesController : ControllerBase { // GET api/values [HttpGet] public ActionResult<IEnumerable<string>> Get() { return new string[] { "value1", "value2" }; } // GET api/values/5 [HttpGet("{id}")] public ActionResult<string> Get(int id) { return "value"; } // POST api/values [HttpPost] public void Post([FromBody] string value) { } // PUT api/values/5 [HttpPut("{id}")] public void Put(int id, [FromBody] string value) { } // DELETE api/values/5 [HttpDelete("{id}")] public void Delete(int id) { } } }
Startup.cs也加入了相关的MVC的服务和中间件
using System; using System.Collections.Generic; using System.Linq; using System.Threading.Tasks; using Microsoft.AspNetCore.Builder; using Microsoft.AspNetCore.Hosting; using Microsoft.AspNetCore.Http; using Microsoft.AspNetCore.HttpsPolicy; using Microsoft.AspNetCore.Mvc; using Microsoft.Extensions.Configuration; using Microsoft.Extensions.DependencyInjection; namespace WebApplication6 { public class Startup { public Startup(IConfiguration configuration) { Configuration = configuration; } public IConfiguration Configuration { get; } // This method gets called by the runtime. Use this method to add services to the container. public void ConfigureServices(IServiceCollection services) { services.Configure<CookiePolicyOptions>(options => { // This lambda determines whether user consent for non-essential cookies is needed for a given request. options.CheckConsentNeeded = context => true; options.MinimumSameSitePolicy = SameSiteMode.None; }); services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1); } // 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(); } else { app.UseExceptionHandler("/Error"); app.UseHsts(); } app.UseHttpsRedirection(); app.UseStaticFiles(); app.UseCookiePolicy(); app.UseMvc(); } } }
Web 应用程序-Razor Page
在ASP.NET MVC中Razor作为一个高级视图引擎存在，Razor提供了一种新的标记语义，其大大减少了用户输入且具有表现力，主要的特点是使用@符号去书写标记。 而在ASP.NET Core中Razor不仅仅是一种视图引擎，其提供了一种新的页面设计方式——Razor Page。其主要的特点在于：
- 基于文件路径的路由系统；
- Razor Page类似于WebForm，一种MVVM的架构，支持双向绑定；
- Razor Page符合单一职责原则，每个页面独立存在，视图和代码紧密组织在一起。
Web 应用程序-MVC
using System; using System.Collections.Generic; using System.Diagnostics; using System.Linq; using System.Threading.Tasks; using Microsoft.AspNetCore.Mvc; using WebApplication5.Models; namespace WebApplication5.Controllers { public class HomeController : Controller { public IActionResult Index() { return View(); } public IActionResult About() { ViewData["Message"] = "Your application description page."; return View(); } public IActionResult Contact() { ViewData["Message"] = "Your contact page."; return View(); } public IActionResult Privacy() { return View(); } [ResponseCache(Duration = 0, Location = ResponseCacheLocation.None, NoStore = true)] public IActionResult Error() { return View(new ErrorViewModel { RequestId = Activity.Current?.Id ?? HttpContext.TraceIdentifier }); } } }
