コード例 #1
0
        public static void AddUpdateDeleteEntityConnectedMode()
        {
            Console.WriteLine("Adding a new student in connected mode started");

            using (var context = new mySchooldbEntities())
            {
                context.Database.Log = Console.WriteLine;
                //for insertion you need to add the entity into the list of
                //objects and then save it
                var newStudent = context.Students.Add(new Student()
                {
                    StudentName    = "Reza4",
                    StudentAddress = new StudentAddress()
                    {
                        Address1 = "address 12",
                        City     = "Montreal"
                    },
                    Height = decimal.Parse("2.5")
                });

                context.SaveChanges();

                //for update you need to take the object and then modify it
                //and then save it back again
                newStudent.StudentName = "update name";
                context.SaveChanges();

                context.Students.Remove(newStudent);
                context.SaveChanges();
            }
        }
コード例 #2
0
        private static void AddUpdateDeleteEntityDisConnectedMode()
        {
            Console.WriteLine("Adding a new student in disconnected mode started");
            var newStudent = new Student()
            {
                StudentName = "new good student"
            };
            var existingStudent = new Student()
            {
                StudentID = 64, StudentName = "is update by me"
            };

            //Keep in mind if any exception happens during the transaction
            //all the transacation will be rollbacked and cancelled
            using (var context = new mySchooldbEntities())
            {
                context.Database.Log = Console.WriteLine;


                context.Entry(existingStudent).State = existingStudent.StudentID == 0 ?
                                                       System.Data.Entity.EntityState.Added : System.Data.Entity.EntityState.Modified;

                context.Entry(newStudent).State = newStudent.StudentID == 0 ?
                                                  System.Data.Entity.EntityState.Added : System.Data.Entity.EntityState.Modified;


                context.SaveChanges();
            }
            Console.WriteLine("Adding a new student disconnected mode is finished");
        }