#define A
#if B
using Model.B;
using DBaccess.B;
#endif
#if A
using Model.A;
using DBaccess.A;
#endif

public class DMbase{protected DbContext db;public DMbase(DbContext db){this.db = db;}/// <summary>/// select one/// </summary>/// <typeparam name="T"></typeparam>/// <param name="entity">这里的entity并无实际作用，只是用于编译器推敲类型</param>/// <param name="predicate">λ表达式</param>/// <returns>返回第一条匹配的记录，若无记录返回null</returns>public virtual T FindOne<T>(T entity, Func<T, bool> expression) where T : class, new(){return this.db.Set<T>().FirstOrDefault(expression);}/// <summary>/// select all/// </summary>/// <typeparam name="T"></typeparam>/// <param name="entity">这里的entity并无实际作用，只是用于编译器推敲类型</param>public virtual IQueryable<T> FindAll<T>(T entity) where T : class, new(){return this.db.Set<T>();}public virtual void Insert<T>(params T[] entities)where T : class, new(){if (entities != null && entities.Length > 0){var set = this.db.Set<T>();foreach (var item in entities){set.Add(item);}}}public virtual void Delete<T>(params T[] entities)where T : class, new(){if (entities != null && entities.Length > 0){var set = this.db.Set<T>();foreach (var item in entities){set.Remove(item);}}}/// <summary>/// 提交事务/// </summary>public void Commit(){this.db.SaveChanges();}}

        public object FindAllTeacher(){//取得一个Contextvar context = ContextFactory.GetContext();//从Factory中取得Teacher和Contact//这里必须要用varvar a = ModelFactory.GetTeacher();var b = ModelFactory.GetContact();var aList = ModelListFactory.GetTeacherList();DMbase dm = new DMbase(context);//用之前取得的Teacher与Contact传入DM层，方便编译器推敲类型var contact = dm.FindAll(b);var teacher = dm.FindAll(a);//业务逻辑，将Teacher与Contact关联起来var result = teacher.Join(contact, o => o.ID, r => r.TeacherID, (o, r) => new { tt = o, aa = r });result = result.OrderByDescending(o => o.aa.Email);//处理数据foreach (var item in result){a = item.tt;a.Contact = item.aa;aList.Add(a);}return aList;}

        public bool AddTeacher<T, T1>(T teacher, T1 contact)where T : class,new()where T1 : class,new(){try{var context = ContextFactory.GetContext();DMbase dm = new DMbase(context);dm.Insert(teacher);dm.Insert(contact);dm.Commit();return true;}catch{return false;}}