Startup.cs 作用就是，对项目中用到的 静态文件，管道，服务，日志，路由，数据库连接，过滤器的注册 等 所有的有关程序的启动运行中用到的
没有startup.cs可以手动新建一个Startup.cs类（具体代码可视自身情况修改）
public class Startup
{public Startup(IConfiguration configuration){Configuration = configuration;}public IConfiguration Configuration { get; }//在依赖注入容器中注册服务public void ConfigureServices(IServiceCollection services){services.AddSingleton<IDbConfig.IDbConfig, DbConfig.DbConfig>();services.AddTransient<IBaseService, BaseService>();services.AddControllers();services.AddSwaggerGen(c =>{c.SwaggerDoc("v1", new OpenApiInfo { Title = "这里填写项目的名称", Version = "v1" });});}public void Configure(IApplicationBuilder app, IWebHostEnvironment env){if(env.IsDevelopment()){app.UseDeveloperExceptionPage();app.UseSwagger();app.UseSwaggerUI(c => c.SwaggerEndpoint("/swagger/v1/swagger.json", "这里填写项目的名称 v1"));}app.UseRouting();app.UseAuthorization();app.UseEndpoints(endpoints =>{endpoints.MapControllers();});}
}上面写完后可以就到了第二步
program.cs内部更新逻辑
Startup.cs 类所需的所有对象都存在于 builder 对象中，因此我们可以将所需的对象传递给和方法。
var builder = WebApplication.CreateBuilder(args);var startup = new Startup(builder.Configuration);
startup.ConfigureServices(builder.Services);var app = builder.Build();
startup.Configure(app, builder.Environment);
)
)
