dhl:vs2010 -EF4.0 数据层： 通过反射返回泛型的工厂
最近用vs2010做项目，想到了数据层Linq To Entity的实现和以后的扩展，想以接口的形式实现。
总体架构图：
数据层Data：
普通的数据操作数据层：
接口IUserRepository：
public interface IUserRepository
{
IList<UserAccount> GetCommonInterestsUser(int UIN);
void AddUser();....
}
接口的实现类UserRepository:
public class UserRepository:IUserRepository
{
private TaoXueDBEntities _TaoXueDBEntities = new TaoXueDBEntities();
public IList<UserAccount> GetCommonInterestsUser(int UIN)
{
return _TaoXueDBEntities.GetMyLike(UIN).ToList();
}
}
工厂:
public class RepositoryFactory
{
private readonly IDictionary<String, Object> factory = new Dictionary<String, Object>();
/// <summary>
/// 获取用户Repository
/// </summary>
/// <returns>用户仓储接口</returns>
public IUserRepository GetUserRepository()
{
string className = "Taoxue.Data.UserRepository";
if (factory.ContainsKey(className)) return factory[className] as UserRepository;
IUserRepository repo = Activator.CreateInstance(Type.GetType(className)) as IUserRepository;
factory.Add(className, repo);
return repo;
}
}
泛型的数据接口：
代码
public interface IRepository<T> where T : class
{
int Add(T entity);
int Count(ICriteria criteria);
int Delete(T entity);
int ExecuteStoreCommand(string commandText, params ObjectParameter[] paramete);
ObjectResult<T> ExecuteStoreQuery(string commandText, params ObjectParameter[] paramete);
IList<T> Find(ICriteria criteria, int page, int pageSize, OrderBy orderExpr);
IList<T> FindAll();
IList<T> FindAll(Func<T, bool> exp);
ObjectSet<T> FindQuerySet() ;
ObjectContext GetObjectContext();
ObjectQuery<T> GetQuery(string query, params ObjectParameter[] parameter);
int SaveChanges();
int Update(T entity);
}
泛型的实现类：
public class Repository<T> : IRepository<T> where T : class
{
private ObjectContext _objectContext = null;
#region objectContext
/// <summary>
/// 获得提供用于查询和使用对象形式的实体数据功能
/// </summary>
/// <returns>数据库上下文</returns>
public virtual ObjectContext GetObjectContext()
{
return new TaoXueDBEntities();
}
#endregion
public Repository()
{
}
/// <summary>
/// 按条件查询所有对象
/// </summary>
/// <param name="exp">表达式</param>
/// <returns>查询结果</returns>
public IList<T> FindAll(Func<T, bool> exp)
{
using (var objectContext = GetObjectContext())
{
var result = objectContext.CreateObjectSet<T>().Where(exp).ToList();
return result;
}
}
/// <summary>
/// 返回所有对象
/// </summary>
/// <returns></returns>
public IList<T> FindAll()
{
using (var objectContext = GetObjectContext())
{
var v = objectContext.CreateObjectSet<T>();
return v.ToList();
}
}
/// <summary>
/// 获取数据集实例，用于查询，修改，添加，删除
/// </summary>
/// <returns></returns>
public ObjectSet<T> FindQuerySet()
{
if (_objectContext == null)
{
_objectContext = GetObjectContext();
}
var result = _objectContext.CreateObjectSet<T>();
return result;
}
/// <summary>
/// ESQL查询,绑定了EF框架
/// </summary>
/// <param name="query">ESQL语句</param>
/// <param name="parameter">参数(可选)</param>
/// <returns></returns>
public ObjectQuery<T> GetQuery(string query, params ObjectParameter[] parameter)
{
using (var objectContext = GetObjectContext())
{
var result = objectContext.CreateQuery<T>(query, parameter);
return result;
}
}
/// <summary>
/// 执行数据源语句(如SQL)，返回影响的行数
/// </summary>
/// <param name="commandText">查询语句</param>
/// <param name="parameter">参数(可选)</param>
/// <returns></returns>
public int ExecuteStoreCommand(string commandText, params ObjectParameter[] paramete)
{
if (string.IsNullOrEmpty(commandText))
{
return -1;
}
using (var objectContext = GetObjectContext())
{
var result = objectContext.ExecuteStoreCommand(commandText, paramete);
return result;
}
}
/// <summary>
/// 执行数据源查询语句(如SQL)，获得数据查询列表
/// </summary>
/// <param name="commandText">查询语句</param>
/// <param name="parameter">参数(可选)</param>
/// <returns></returns>
public ObjectResult<T> ExecuteStoreQuery(string commandText, params ObjectParameter[] paramete)
{
using (var objectContext = GetObjectContext())
{
var result = objectContext.ExecuteStoreQuery<T>(commandText, paramete);
return result;
}
}
/// <summary>
/// 添加对象
/// </summary>
/// <param name="entity"></param>
/// <returns>修改成功的对象数</returns>
public int Add(T entity)
{
using (var objectContext = GetObjectContext())
{
objectContext.CreateObjectSet<T>().AddObject(entity);
var result = objectContext.SaveChanges();
return result;
}
}
/// <summary>
/// 删除对象
/// </summary>
/// <param name="entity">将被删除的对象</param>
/// <returns>删除的数量</returns>
public int Delete(T entity)
{
//objectContext.Attach(entity);
using (var objectContext = GetObjectContext())
{
try
{
objectContext.CreateObjectSet<T>().Attach(entity);
objectContext.CreateObjectSet<T>().DeleteObject(entity);
}
catch (Exception e)
{
//todo:log it e
}
var result = objectContext.SaveChanges();
return result;
}
}
/// <summary>
/// 提交所有修改
/// </summary>
public int SaveChanges()
{
if (_objectContext != null)
return _objectContext.SaveChanges();
else
return -1;
}
/// <summary>
/// 更新对象
/// </summary>
/// <param name="entity"></param>
/// <returns></returns>
public int Update(T entity)
{
using (var objectContext = GetObjectContext())
{
objectContext.CreateObjectSet<T>().Attach(entity);
//objectContext.SetAllModified(entity);
objectContext.ObjectStateManager.ChangeObjectState(entity, EntityState.Modified);//EF4 新语法
try
{
var result = objectContext.SaveChanges();
return result;
}
catch (OptimisticConcurrencyException e)
{
objectContext.Refresh(RefreshMode.ClientWins, entity); // Last in wins
//logger.Write(e);
var result = objectContext.SaveChanges();
return result;
}
}
//using (var ctx = new AdventureWorksEntities())
//{
// // 先 ApplyChanges() 再 ChangeObjectState(), ChangeRelationshipState()
// ctx.ProductCategories.ApplyChanges(category);
// ctx.ObjectStateManager.ChangeObjectState(category, EntityState.Modified);
// return ctx.SaveChanges();
//}
}
}
工厂RepositoryFactory：
代码
public class RepositoryFactory
{
private readonly IDictionary<String, Object> factory = new Dictionary<String, Object>();
#region RepositoryFactory 为单例
/// <summary>
/// RepositoryFactory 为单例模式
/// </summary>
private static RepositoryFactory Instance;
private RepositoryFactory()
{
}
/// <summary>
/// 获取Repository工厂实例
/// </summary>
/// <returns>Repository工厂实例</returns>
public static RepositoryFactory GetInstance()
{
if (Instance == null) Instance = new RepositoryFactory();
return Instance;
}
#endregion
#region 工厂方法：通过反射返回泛型数据操作接口的实现类
/// <summary>
/// 获取实体类的Repository的接口IRepository
/// </summary>
/// <typeparam name="T">实体Entity</typeparam>
/// <returns>泛型IRepository</returns>
public IRepository<T> GetRepository<T>() where T : class
{
Type t = typeof(T);
if (factory.ContainsKey("Repository" + t.FullName)) return factory["Repository" + t.FullName] as IRepository<T>;
string className = "Taoxue.Data.Repository`1";
className += "[[" + t.FullName + "," + t.Assembly.FullName + "]]";
Type type = Type.GetType(className);
IRepository<T> repo = Activator.CreateInstance(type) as IRepository<T>;
factory.Add("Repository" + t.FullName, repo);
return repo;
}
#endregion
#region 工厂方法：通过反射返回其他数据操作接口的实现类
/// <summary>
/// 获取用户Repository
/// </summary>
/// <returns>用户仓储接口</returns>
public IUserRepository GetUserRepository()
{
string className = "Taoxue.Data.UserRepository";
if (factory.ContainsKey(className)) return factory[className] as UserRepository;
IUserRepository repo = Activator.CreateInstance(Type.GetType(className)) as IUserRepository;
factory.Add(className, repo);
return repo;
}
public ITaokeRepository GetTaoxueRepository()
{
const string className = "Taoxue.Data.TaokeRepository";
if (factory.ContainsKey(className)) return factory[className] as ITaokeRepository;
var repo = Activator.CreateInstance(Type.GetType(className)) as ITaokeRepository;
factory.Add(className, repo);
return repo;
}
#endregion
}
上层业务的调用：
IRepository<Lesson> repository = RepositoryFactory.GetInstance().GetRepository<Lesson>();
IList<Lesson> listAll = repository.FindAll();
return listAll;
