.NET Core 2.1 升級 .NET Core 3.1 踩坑（二）

目錄

問題描述

Startup 文件對比

.Net Core 2.1

.Net Core 3.1

解決辦法

---

問題描述

無法使用 app.UseMvc(options) 方法

Startup 文件對比

.Net Core 2.1

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.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
            {
                // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
                app.UseHsts();
            }

            app.UseHttpsRedirection();
            app.UseMvc();
        }
    }

.Net Core 3.1

 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.AddControllers();
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }

            app.UseHttpsRedirection();

            app.UseRouting();

            app.UseAuthorization();

            app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllers();
            });
        }
    }

解決辦法

將 .Net Core 2.1 的 Startup 文件修改成 .net Core 3.1 版本的即可；標準的模版參考如上代碼。項目具體解決參考如下代碼：

 // This method gets called by the runtime. Use this method to add services to the container.
        public void ConfigureServices(IServiceCollection services)
        {
    services.AddMvc(options => options.EnableEndpointRouting = false)
                .SetCompatibilityVersion(CompatibilityVersion.Latest);

            services.AddControllers(); 
        }

// 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
            {
                //https://localhost:44367/swagger/v1.0/index.html
                app.UseExceptionHandler("/Error");
                // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
                app.UseHsts();
            }

            app.UseHttpsRedirection();
            app.UseStaticFiles();
            
            // 2.1 > 3.1將 UseMvcWithDefaultRoute() 改爲 UseRouting() + UseEndpoints() 就可以了
            //app.UseMvc(routes =>
            //{
            //    routes.MapRoute(
            //        name: "default",
            //        template: "cese2/{controller}/{action=Index}/{id?}");
            //});

            app.UseRouting();
            app.UseAuthorization();  
            app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllerRoute(
                    name: "default",
                    pattern: "cese2/{controller}/{action=Index}/{id?}");
                //endpoints.MapRazorPages();
                endpoints.MapControllers();
            });
        }