namespace CoreBackend.Api
{ public class Program
    { public static void Main(string[] args)
        {
            BuildWebHost(args).Run();
        } public static IWebHost BuildWebHost(string[] args) => WebHost.CreateDefaultBuilder(args)
                .UseStartup<Startup>()
                .Build();
    }
}

namespace CoreBackend.Api
{ 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)
        {
        } // This method gets called by the runtime. Use this method to configure the HTTP request pipeline. public void Configure(IApplicationBuilder app, IHostingEnvironment env)
        { //判断是否是环境变量 if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            } //这个就是一个简单的中间件写法 app.Run(async (context) => { await context.Response.WriteAsync("Hello World!");
            });
        }
    }
}

        public void Configure(IApplicationBuilder app, IHostingEnvironment env)
        { if (env.IsDevelopment())
            { // 在开发环境中，使用异常页面，这样可以暴露错误堆栈信息，所以不要放在生产环境。  app.UseDeveloperExceptionPage();
            } else {
                app.UseExceptionHandler("/Error"); // 在非开发环境中，使用HTTP严格安全传输(or HSTS) 对于保护web安全是非常重要的。 // 强制实施 HTTPS 在 ASP.NET Core，配合 app.UseHttpsRedirection //app.UseHsts();  } #region Swagger app.UseSwagger();
            app.UseSwaggerUI(c => { //之前是写死的 //c.SwaggerEndpoint("/swagger/v1/swagger.json", "ApiHelp V1"); //c.RoutePrefix = "";//路径配置，设置为空，表示直接在根域名（localhost:8001）访问该文件,注意localhost:8001/swagger是访问不到的，去launchSettings.json把launchUrl去掉 //根据版本名称倒序 遍历展示 typeof(ApiVersions).GetEnumNames().OrderByDescending(e => e).ToList().ForEach(version => {
                    c.SwaggerEndpoint($"/swagger/{version}/swagger.json", $"{ApiName} {version}");
                });
            }); #endregion #region Authen //app.UseMiddleware<JwtTokenAuth>();//注意此授权方法已经放弃，请使用下边的官方验证方法。但是如果你还想传User的全局变量，还是可以继续使用中间件  app.UseAuthentication(); #endregion #region CORS //跨域第二种方法，使用策略，详细策略信息在ConfigureService中 app.UseCors("LimitRequests");//将 CORS 中间件添加到 web 应用程序管线中, 以允许跨域请求。 //跨域第一种版本，请要ConfigureService中配置服务 services.AddCors(); // app.UseCors(options => options.WithOrigins("http://localhost:8021").AllowAnyHeader() //.AllowAnyMethod());  #endregion // 跳转https  app.UseHttpsRedirection(); // 使用静态文件  app.UseStaticFiles(); // 使用cookie  app.UseCookiePolicy(); // 返回错误码 app.UseStatusCodePages();//把错误码返回前台，比如是404  app.UseMvc();
        }

        public void ConfigureServices(IServiceCollection services)
        {
            services.AddMvc(); // 注册MVC到Container
        }

        public void Configure(IApplicationBuilder app, IHostingEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }
            else
            {
                app.UseExceptionHandler();
            }

            app.UseMvc();

//以下不是本系列教程，就看思路即可，不用敲代码 namespace CoreBackend.Api.Controllers
{
    //[Route("api/product")]
    [Route("api/[controller]")]
    public class ProductController: Controller
    {
        [HttpGet]
        public JsonResult GetProducts()
        {
            return new JsonResult(new List<Product>
            {
                new Product
                {
                    Id = 1,
                    Name = "牛奶",
                    Price = 2.5f
                },
                new Product
                {
                    Id = 2,
                    Name = "面包",
                    Price = 4.5f
                }
            });
        }
    }
}

//以下不是本系列教程，就看思路即可，不用敲代码  [Route("{id}", Name = "GetProduct")]
        public IActionResult GetProduct(int id)
        {
            var product = ProductService...(x => x.Id == id);
            if (product == null)
            {
                return NotFound();
            }
            return Ok(product);
        }

        [HttpPost]
        public IActionResult Post([FromBody] ProductCreation product)
        {
            if (product == null)
            {
                return BadRequest();
            }
            var maxId = ProductService.Max(x => x.Id);
            var newProduct = new Product
            {
                Id = ++maxId,
                Name = product.Name,
                Price = product.Price
            };
            ProductService.Add(newProduct);

            return CreatedAtRoute("GetProduct", new { id = newProduct.Id }, newProduct);
        }

//以下不是本系列教程，就看思路即可，不用敲代码 using System;
using System.ComponentModel.DataAnnotations;

namespace CoreBackend.Api.Dtos
{
    public class ProductCreation
    {
        [Display(Name = "产品名称")]
        [Required(ErrorMessage = "{0}是必填项")]
        // [MinLength(2, ErrorMessage = "{0}的最小长度是{1}")]
        // [MaxLength(10, ErrorMessage = "{0}的长度不可以超过{1}")]
　　　　 [StringLength(10, MinimumLength = 2, ErrorMessage = "{0}的长度应该不小于{2}, 不大于{1}")]
        public string Name { get; set; }

        [Display(Name = "价格")]
        [Range(0, Double.MaxValue, ErrorMessage = "{0}的值必须大于{1}")]
        public float Price { get; set; }
    }
}

//以下不是本系列教程，就看思路即可，不用敲代码  [HttpPost]
        public IActionResult Post([FromBody] ProductCreation product)
        {
            if (product == null)
            {
                return BadRequest();
            }

            if (!ModelState.IsValid)
            {
                return BadRequest(ModelState);
            }

            var maxId = ProductService.Max(x => x.Id);
            var newProduct = new Product
            {
                Id = ++maxId,
                Name = product.Name,
                Price = product.Price
            };
            ProductService.Add(newProduct);

            return CreatedAtRoute("GetProduct", new { id = newProduct.Id }, newProduct);
        }

    public class ProductModification
    {
        [Display(Name = "产品名称")]
        [Required(ErrorMessage = "{0}是必填项")]
        [StringLength(10, MinimumLength = 2, ErrorMessage = "{0}的长度应该不小于{2}, 不大于{1}")]
        public string Name { get; set; }

        [Display(Name = "价格")]
        [Range(0, Double.MaxValue, ErrorMessage = "{0}的值必须大于{1}")]
        public float Price { get; set; }
    }

//以下不是本系列教程，就看思路即可，不用敲代码  

[HttpPut("{id}")]
        public IActionResult Put(int id, [FromBody] ProductModification product)
        {
            if (product == null)
            {
                return BadRequest();
            }

            if (product.Name == "产品")
            {
                ModelState.AddModelError("Name", "产品的名称不可以是'产品'二字");
            }

            if (!ModelState.IsValid)
            {
                return BadRequest(ModelState);
            }

            var model = ProductService.SingleOrDefault(x => x.Id == id);
            if (model == null)
            {
                return NotFound();
            }
            model.Name = product.Name;
            model.Price = product.Price;

            // return Ok(model);
            return NoContent();
        }