Startup.cs

using IGeekFan.AspNetCore.Knife4jUI;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Mvc.Controllers;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Microsoft.OpenApi.Models;
using System.IO;

namespace Knife4jUIDemo
{
    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();
            services.Configure<Knife4UIOptions>(c =>
            {
                Configuration.Bind("Knife4UI", c);
            });
            services.AddSwaggerGen(c =>
            {
                c.SwaggerDoc("v1", new OpenApiInfo { Title = "API V1", Version = "v1" });
                c.AddServer(new OpenApiServer()
                {
                    Url = "http://localhost:81/admin/",
                    Description = "vvv"
                });

                c.CustomOperationIds(apiDesc =>
                {
                    var controllerAction = apiDesc.ActionDescriptor as ControllerActionDescriptor;
                    return controllerAction.ControllerName + "-" + controllerAction.ActionName;
                });

                //var filePath = Path.Combine(System.AppContext.BaseDirectory, "Knife4jUIDemo.xml");
                //c.IncludeXmlComments(filePath, true);
            });
        }

        // 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.UseSwagger();

            app.UseSwaggerUI(c =>
            {
                c.SwaggerEndpoint("v1/swagger.json", "My API V1");
                //c.SwaggerEndpoint("/v1/api-docs", "LinCms");
            });

            app.UseKnife4UI(c =>
            {
                c.RoutePrefix = ""; // serve the UI at root
                c.SwaggerEndpoint("/v1/swagger.json", "V1 Docs");
            });

            app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllers();
                endpoints.MapSwagger("{documentName}/swagger.json");
            });
        }
    }
}