public void Run() { bool inMenu = true; int command; while (inMenu) { PrintSpaces(); Console.Write(GetMenu()); try { command = Int32.Parse(Console.ReadLine()); } catch (Exception e) { continue; } switch (command) { case 1: Student s = ReadStudent(); if (s == null) { Console.Write("Incorrect data."); } else { Console.Write(service.AddStudent(s) + "\n"); } break; case 2: s = ReadStudent(); if (s == null) { Console.Write("Incorrect data."); } else { Console.Write(service.UpdateStudent(s) + "\n"); } break; case 3: Console.Write("Id: "); string id = Console.ReadLine(); if (id == null) { Console.Write("Incorrect data."); } else { Console.Write(service.DeleteStudent(id) + "\n"); } break; case 0: inMenu = false; break; } } }