<EntityType Name="UserAccout"><Key><PropertyRef Name="Id" /></Key><Property Name="Id" Type="Int32" Nullable="false" annotation:StoreGeneratedPattern="Identity" /><Property Name="FirstName" Type="String" Nullable="false" /><Property Name="LastName" Type="String" Nullable="false" /><Property Name="AuditFileds" Type="OrderDB.AuditFields" Nullable="false" /><Property Name="Timestamp" Type="DateTime" Nullable="false" ConcurrencyMode="Fixed" annotation:StoreGeneratedPattern="Computed" /></EntityType>

#region （4.1）测试不设置任何并发测试时，当产生并发EF的处理方法delegate void MyDelegate(Address addressValue);public  StringBuilder sb = new StringBuilder();public Address GetAddress(int id){using (OrderDBContainer context = new OrderDBContainer()){IQueryable<Address> list = context.AddressSet.Where(x => x.Id == id);return list.First();}}/// <summary>/// 修改方法/// </summary>/// <param name="addressValue"></param>public void UpdateAddress(Address addressValue){using (OrderDBContainer context = new OrderDBContainer()){//显示输入新数据的信息Display("Current", addressValue);var obj = context.AddressSet.Where(x => x.Id == addressValue.Id).First();if (obj != null)context.Entry(obj).CurrentValues.SetValues(addressValue);//虚拟操作，保证数据能同时加入到上下文当中Thread.Sleep(100);context.SaveChanges();}}        /// <summary>/// 显示实体当前属性/// </summary>/// <param name="message"></param>/// <param name="addressValue"></param>public void Display(string message, Address addressValue){String data = string.Format("{0}\n  Address Message:\n    Id:{1}  Address1:{2}  " +"address2:{3} \r\n ",message, addressValue.Id, addressValue.Address1, addressValue.Address2 );sb.AppendLine(data);}     /// <summary>/// （1）测试使用EF默认的机制，当配置并发控制时，系统是使用的合并的方式/// </summary>/// <param name="sender"></param>/// <param name="e"></param>private void button3_Click(object sender, EventArgs e){//在更新数据前显示对象信息var beforeObj = GetAddress(1);Display("Before", beforeObj);//更新Person的SecondName，Age两个属性Address _address1 = new Address();_address1.Id = 1;_address1.Address1 = "古溪";_address1.Address2 = beforeObj.Address2;_address1.AuditFields.InsertDate = beforeObj.AuditFields.InsertDate;_address1.AuditFields.UpdateDate = beforeObj.AuditFields.UpdateDate;_address1.City = beforeObj.City;_address1.Zip = beforeObj.Zip;_address1.State = beforeObj.State;//更新Person的FirstName属性Address _address2 = new Address();_address2.Id = 1;_address2.Address1 = beforeObj.Address1;_address2.Address2 = "江苏";_address2.AuditFields.InsertDate = beforeObj.AuditFields.InsertDate;_address2.AuditFields.UpdateDate = beforeObj.AuditFields.UpdateDate;_address2.City = beforeObj.City;_address2.Zip = beforeObj.Zip;_address2.State = beforeObj.State;//使用异步方式同时更新数据MyDelegate myDelegate = new MyDelegate(UpdateAddress);myDelegate.BeginInvoke(_address1, null, null);myDelegate.BeginInvoke(_address2, null, null);Thread.Sleep(1000);//在更新数据后显示对象信息var afterObj = GetAddress(1);Display("After", afterObj);this.textBox1.Text = sb.ToString();}/// <summary>/// 先插入几条数据等着测试/// </summary>/// <param name="sender"></param>/// <param name="e"></param>private void BtnSaveAddress_Click(object sender, EventArgs e){using (OrderDBContainer db = new OrderDBContainer()){Address address = new Address();address.Address1 = "古溪镇";address.Address2 = "安镇";address.State = "2";address.City = "无锡";address.AuditFields.InsertDate = DateTime.Now;address.AuditFields.UpdateDate = DateTime.Now;address.Zip = "21415";db.AddressSet.Add(address);db.SaveChanges();}}/// <summary>/// 还原成初始值，准备再次测试/// </summary>/// <param name="sender"></param>/// <param name="e"></param>private void button5_Click(object sender, EventArgs e){using (OrderDBContainer db = new OrderDBContainer()){Address _address = db.AddressSet.Where(x => x.Id == 1).First();_address.Address1 = "aaa";_address.Address2 = "bbb";db.SaveChanges();}}#endregion

/// <summary>/// 修改方法/// </summary>/// <param name="addressValue"></param>public void UpdateAddress(Address addressValue){using (OrderDBContainer context = new OrderDBContainer()){//显示输入新数据的信息Display("Current", addressValue);var obj = context.AddressSet.Where(x => x.Id == addressValue.Id).First();if (obj != null)context.Entry(obj).CurrentValues.SetValues(addressValue);//虚拟操作，保证数据能同时加入到上下文当中Thread.Sleep(100);context.SaveChanges();}}

//更新对象public int UpdateWithConcurrent(int num, Address addressValue){int returnValue = -1;using (OrderDBContainer context = new OrderDBContainer()){var obj = context.AddressSet.Where(x => x.Id == addressValue.Id).First();//显示对象所处状态DisplayState("Before Update", obj);try{if (obj != null)context.Entry(obj).CurrentValues.SetValues(addressValue);//虚拟操作，保证数据已经在数据库中被异步删除Thread.Sleep(300);context.SaveChanges();returnValue = obj.Id;}catch (Exception){//针对异常要做相应的判断，因为我只测试了删除的情况，就写死直接修改成Added 了//正确的是要区分到底是修改还是删除  OptimisticConcurrencyException ex//把对象的状态更改为 Addedcontext.Entry(obj).State = System.Data.Entity.EntityState.Added;context.SaveChanges();returnValue = obj.Id;}}return returnValue;}