private static void 示範實體狀態用法(ContosoUniversityEntities db) { var one = db.Course.Find(14); db.Entry(one).State = System.Data.Entity.EntityState.Modified; db.SaveChanges(); var c = new Course() { CourseID = 14 }; db.Entry(c).State = System.Data.Entity.EntityState.Deleted; db.Course.Remove(c); db.SaveChanges(); Console.WriteLine(db.Entry(one).State); one.Credits += 1; Console.WriteLine(db.Entry(one).State); //db.Entry(one).State = System.Data.Entity.EntityState.Deleted; db.SaveChanges(); Console.WriteLine(db.Entry(one).State); }
private static void SaveChangesWithEntityStates(ContosoUniversityEntities db) { var c = new Course { Title = "Entity Framework 6.1", Credits = 10, Department = db.Department.Find(1) }; db.Course.Add(c); db.SaveChanges(); var id = c.CourseID; db.Entry(c).State = System.Data.Entity.EntityState.Modified; db.SaveChanges(); db.Entry(c).State = System.Data.Entity.EntityState.Detached; var d = new Course { CourseID = id }; db.Entry(d).State = System.Data.Entity.EntityState.Deleted; db.SaveChanges(); }
private static void DeleteCourse(ContosoUniversityEntities db) { var course = db.Course.Find(9); db.Course.Remove(course); db.SaveChanges(); }
private static void ShowEntityStates(ContosoUniversityEntities db) { var one = db.Course.Find(11); Console.WriteLine(db.Entry(one).State); one.Credits += 10; Console.WriteLine(db.Entry(one).State); db.Course.Remove(one); Console.WriteLine(db.Entry(one).State); db.SaveChanges(); Console.WriteLine(db.Entry(one).State); }
private static void AddCourse(ContosoUniversityEntities db) { var course = new Course { Title = "Entity Framework 6", Credits = 100 }; course.Department = db.Department.Find(2); db.Course.Add(course); db.SaveChanges(); }
private static void UpdateCourse(ContosoUniversityEntities db) { var courses = db.Course.Where(c => c.Title.Contains("Git")); foreach (var course in courses) { course.Credits += 10; course.CreatedOn = DateTime.Now; course.UpdatedOn = DateTime.Now; } db.SaveChanges(); }
private static void UpdateCourse(ContosoUniversityEntities db) { var items = db.Course.Where(p => p.Title.Contains("Git")); foreach (var item in items) { item.Credits += 1; item.CreatedOn = DateTime.Now; item.UpdatedOn = DateTime.Now; } db.SaveChanges(); }
private static void AddCourse(ContosoUniversityEntities db) { var c = new Course() { Title = "Entity Framework 6.1", Credits = 100, IsDeleted = false }; c.Department = db.Department.Find(2); db.Course.Add(c); db.SaveChanges(); }
private static void DeleteCourse(ContosoUniversityEntities db) { //var c = db.Course.Find(9); //var c = db.Course.FirstOrDefault(p => p.Title.StartsWith("Git")); //db.Course.Remove(c); var c = db.Course.Where(p => p.Title.StartsWith("Git")); db.Course.RemoveRange(c); db.SaveChanges(); }