static void Main(string[] args)
        {
            //var coursesClient = new CoursesClient("BasicHttpBinding_ICourses"); // Not support session
            var coursesClient = new CoursesClient("NetTcpBinding_ICourses"); //support session

            //coursesClient.AddToCourse(new Course{CourseId = 1, CourseName = "Asp.Net"});
            //coursesClient.AddToCourse(new Course{CourseId = 2, CourseName = "Ado.Net"});
            //coursesClient.AddToCourse(new Course{CourseId = 2, CourseName = "C#.Net" });
            //GetCourses(coursesClient);



            //Enumerable.Range(0, 3).ToList().ForEach(i =>
            //{
            //    Console.WriteLine($"Enter Record {i + 1}");
            //    coursesClient.AddToCourse(new Course(){CourseId = int.Parse(Console.ReadLine()), CourseName = Console.ReadLine()});
            //});
            //GetCourses(coursesClient);



            //coursesClient.AddToCourse(new Course { CourseId = 1, CourseName = "Asp.Net" });
            //coursesClient.AddToCourse(new Course { CourseId = 2, CourseName = "Ado.Net" });
            //coursesClient.AddToCourse(new Course { CourseId = 2, CourseName = "C#.Net" });

            //Thread.Sleep(5000);

            //GetCourses(coursesClient);



            coursesClient.AddToCourse(new Course {
                CourseId = 1, CourseName = "Asp.Net"
            });
            GetCourses(coursesClient);

            // 세션이 끝나면 객체를 새로 만들어줘야 한다.
            coursesClient = new CoursesClient("NetTcpBinding_ICourses"); //support session
            coursesClient.AddToCourse(new Course {
                CourseId = 1, CourseName = "Asp.Net"
            });
            GetCourses(coursesClient);



            Console.ReadKey();
        }