public static void UpdateRecord() { using (AutoLotEntities context = new AutoLotEntities()) { // EntityKey key = new EntityKey("AutoLotEntities.Cars", "CarID", 2224); Car c = context.Cars.Find(2224); Console.WriteLine(string.Format("Found : {0}", c)); if (c != null) { c.Color = "Blue"; context.SaveChanges(); } Console.WriteLine("changed 2224 to blue"); // Car carToDelete = context. } }
private static void RemoveRecord() { using (AutoLotEntities context = new AutoLotEntities()) { //查找实体,如果存在则将其删除 Car carToDelete = (Car)context.Cars.Where(g => g.CarID == 2222).Select(g => g).FirstOrDefault(); if (carToDelete != null) { context.Cars.Remove(carToDelete); context.SaveChanges(); } } }
private static void UpdateRecord() { using (AutoLotEntities context = new AutoLotEntities()) { Car carToUpdate = (from car in context.Cars where car.CarID == 2222 select car).FirstOrDefault(); if (carToUpdate != null) { carToUpdate.CarNickName = "LiPengfei"; context.SaveChanges(); } } }
public static void RemoveRecord() { using (AutoLotEntities context = new AutoLotEntities()) { // EntityKey key = new EntityKey("AutoLotEntities.Cars", "CarID", 2224); // Car c = context.Cars.Find(2224); Car c = (from car in context.Cars where car.CarID == 2224 select car).FirstOrDefault(); Console.WriteLine(string.Format("Found : {0}" ,c)); if (c != null) { context.Cars.Remove(c); context.SaveChanges(); } Console.WriteLine("removed 2224"); // Car carToDelete = context. } }
private static void RemoveRecordWithLINQ() { // Find a car to delete by primary key. using (AutoLotEntities context = new AutoLotEntities()) { // See if we have it. var carToDelete = (from c in context.Cars where c.CarID == 2222 select c).FirstOrDefault(); if (carToDelete != null) { context.DeleteObject(carToDelete); context.SaveChanges(); } } }
private static void UpdateRecord() { // 通过主键查找要更新的汽车 using (AutoLotEntities context = new AutoLotEntities()) { // 为查找的实体定义主键 EntityKey key = new EntityKey("AutoLotEntities.Cars", "CarID", 2222); // 查找实体,如果存在的话将其删除 Car carToUpdate = (Car)context.GetObjectByKey(key); if (carToUpdate != null) { carToUpdate.Color = "Blue"; context.SaveChanges(); } } }
private static void UpdateRecord() { // Find a car to delete by primary key. using (AutoLotEntities context = new AutoLotEntities()) { // Define a key for the entity we are looking for. EntityKey key = new EntityKey("AutoLotEntities.Cars", "CarID", 2222); // Grab the car, change it, save! Car carToUpdate = (Car)context.GetObjectByKey(key); if (carToUpdate != null) { carToUpdate.Color = "Blue"; context.SaveChanges(); } } }
private static void RemoveRecord() { // Find a car to delete by primary key. using (AutoLotEntities context = new AutoLotEntities()) { // Define a key for the entity we are looking for. EntityKey key = new EntityKey("AutoLotEntities.Cars", "CarID", 2222); // See if we have it. Car carToDelete = (Car)context.GetObjectByKey(key); if (carToDelete != null) { context.DeleteObject(carToDelete); context.SaveChanges(); } } }
private static void AddNewRecord() { // Add record to the Inventory table of the AutoLot // database. using (AutoLotEntities context = new AutoLotEntities()) { try { context.Cars.AddObject(new Car() { CarID = 2222, Make = "Yugo", Color = "Brown" }); context.SaveChanges(); } catch (Exception ex) { Console.WriteLine(ex.InnerException.Message); } } }
private static void AddNewRecord() { using (AutoLotEntities context = new AutoLotEntities()) { try { context.Cars.Add(new Car() { CarID = 2222, Make = "Yugo", Color = "Brown" }); context.SaveChanges(); } catch (Exception ex) { Console.WriteLine(ex.InnerException.Message); } } }
private static void RemoveRecord() { // 通过主键查找要删除的汽车 using (AutoLotEntities context = new AutoLotEntities()) { // 为查找的实体定义主键 //EntityKey key = new EntityKey("AutoLotEntity.Cars", "CarID", 2222); // 查找实体,如果存在的话将其删除 //Car carToDelete = (Car)context.GetObjectByKey(key); var carToDelete = (from c in context.Cars where c.CarID == 2222 select c).FirstOrDefault(); if (carToDelete != null) { context.DeleteObject(carToDelete); context.SaveChanges(); } } }
private static void AddNewRecord() { // 向AutoLot数据库的Inventory表添加一条记录 using (AutoLotEntities context = new AutoLotEntities()) { try { // 对新的记录进行硬编码,仅供测试 context.AddToCars(new Car() { CarID = 2222, Make = "Yugo", Color = "Brown" }); context.SaveChanges(); } catch (Exception ex) { Console.WriteLine(ex.InnerException.Message); } } }
private static void AddNewRecord() { using (AutoLotEntities context = new AutoLotEntities()) { try { context.Cars.Add(new Car() { CarID = 2224, Make = "Yugo", Color = "Brown" }); context.SaveChanges(); Console.WriteLine("added 2224"); } catch (DbUpdateException ex) { Exception e = ex; Console.WriteLine(ex == ex.InnerException); while (e != null) { Console.WriteLine(e.Message); e = e.InnerException; } } catch (Exception ex) { Console.WriteLine(ex); } } }
private static void UpdateRecord() { // Find a car to delete by primary key. using (AutoLotEntities context = new AutoLotEntities()) { // Define a key for the entity we are looking for. EntityKey key = new EntityKey("AutoLotEntities.Cars", "CarID", 2222); // Grab the car, change it, save! Car carToUpdate = (Car)context.GetObjectByKey(key); Console.WriteLine(carToUpdate.EntityState); if (carToUpdate != null) { carToUpdate.Color = "Blue"; context.SaveChanges(); } } }