public void Configure(IApplicationBuilder app, IWebHostEnvironment env, IHostApplicationLifetime appLife)
        {
            Console.WriteLine("Configure...");
            
            //注册服务启动完成事件
            appLife.ApplicationStarted.Register(() =>
            {             
                Console.WriteLine("/***************************************************/");
                Console.WriteLine("Server start successfully.");
                Console.WriteLine("/***************************************************/");
            });

            appLife.ApplicationStopping.Register(() =>
            {
                Console.WriteLine("Server Stopping...");
            });

            appLife.ApplicationStopped.Register(() =>
            {
                Console.WriteLine("Server Stopped.");
            });

    // 省略....
}