Entity Framework 第一篇

这段时间研究了orm框架EF 写一写研究的历程和心得

先贴上核心代码

 public interface ITransaction
{
bool IsTransaction { get;} void BeginTransaction(); int Commit(); void Rollback();
}
 public class BaseRepository : ITransaction, IDisposable
{ private XFDbContext dbContext; /// <summary>
/// 连接字符串名称
/// </summary>
public string ConnectionName { get; set; } private bool disposed; public BaseRepository()
{
this.dbContext = new XFDbContext();
this.IsTransaction = false;
} public BaseRepository(string connectionName)
{
this.ConnectionName = connectionName;
this.dbContext = new XFDbContext(ConnectionName);
this.IsTransaction = false;
} #region 增删改 /// <summary>
/// 新增实体对象
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="model"></param>
/// <returns></returns>
public int Insert<TEntity>(TEntity model) where TEntity : class
{
return this.ChangeObjectState<TEntity>(model, EntityState.Added);
} /// <summary>
/// 新增实体对象集合
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="models"></param>
/// <returns></returns>
public int Insert<TEntity>(IEnumerable<TEntity> models) where TEntity : class
{
return this.ChangeObjectState<TEntity>(models, EntityState.Added);
} /// <summary>
/// 持久化对象更改
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="model"></param>
/// <returns></returns>
public int Update<TEntity>(TEntity model) where TEntity : class
{
return this.ChangeObjectState<TEntity>(model, EntityState.Modified);
} /// <summary>
/// 更新对象集合
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="models"></param>
/// <returns></returns>
public int Update<TEntity>(IEnumerable<TEntity> models) where TEntity : class
{
return this.ChangeObjectState<TEntity>(models, EntityState.Modified);
} /// <summary>
/// 更新对象部分属性
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="predicate"></param>
/// <param name="updateAction"></param>
/// <returns></returns>
public int Update<TEntity>(Expression<Func<TEntity, bool>> predicate, Action<TEntity> updateAction) where TEntity : class
{
if (predicate == null)
throw new ArgumentNullException("predicate");
if (updateAction == null)
throw new ArgumentNullException("updateAction"); //dbContext.Configuration.AutoDetectChangesEnabled = true;
var _model = dbContext.Set<TEntity>().Where(predicate).ToList();
if (_model == null) return ;
_model.ForEach(p =>
{
updateAction(p);
dbContext.Entry<TEntity>(p).State = EntityState.Modified;
});
return Save();
} /// <summary>
/// 删除实体对象
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="model"></param>
/// <returns></returns>
public int Delete<TEntity>(TEntity model) where TEntity : class
{
return this.ChangeObjectState<TEntity>(model, EntityState.Deleted);
} /// <summary>
/// 删除实体对象集合
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="models"></param>
/// <returns></returns>
public int Delete<TEntity>(IEnumerable<TEntity> models) where TEntity : class
{
return this.ChangeObjectState<TEntity>(models, EntityState.Deleted);
} /// <summary>
/// 删除实体对象集合(符合部分条件的)
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="predicate"></param>
/// <returns></returns>
public int Delete<TEntity>(Expression<Func<TEntity, bool>> predicate) where TEntity : class
{
List<TEntity> _list = null; _list = dbContext.Set<TEntity>().Where(predicate).ToList();
foreach (var item in _list)
{
dbContext.Entry<TEntity>(item).State = EntityState.Deleted;
}
return Save();
} #endregion 增删改 #region 查询
public IList<TEntity> Search<TEntity>(Expression<Func<TEntity, bool>> predicate = null) where TEntity : class
{
if (predicate == null)
{
return dbContext.Set<TEntity>().ToList();
}
else
{
return dbContext.Set<TEntity>().Where(predicate).ToList();
} } /// <summary>
/// 查询单个记录
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="predicate"></param>
/// <returns></returns>
public TEntity SearchFirstOrDefault<TEntity>(Expression<Func<TEntity, bool>> predicate = null) where TEntity : class
{
if (predicate == null)
{
return dbContext.Set<TEntity>().FirstOrDefault();
}
else
{
return dbContext.Set<TEntity>().Where(predicate).FirstOrDefault();
} } /// <summary>
/// 查询多笔记录
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="predicate"></param>
/// <returns></returns>
public IList<TEntity> SearchList<TEntity>(Expression<Func<TEntity, bool>> predicate = null) where TEntity : class
{ if (predicate == null)
{
return dbContext.Set<TEntity>().ToList();
}
else
{
return dbContext.Set<TEntity>().Where(predicate).ToList();
}
} public IList<TEntity> GetPaged<TEntity>(out int total, Expression<Func<TEntity, bool>> filter = null, Func<IQueryable<TEntity>, IOrderedQueryable<TEntity>> orderBy = null, int index = , int size = ) where TEntity : class
{
int skipCount = (index - ) * size;
var query = Get(filter, orderBy);
total = query.Count();
query = skipCount > ? query.Skip(skipCount).Take(size) : query.Take(size);
return query.ToList();
} public IList<TEntity> GetPaged<TEntity>(out int total, Expression<Func<TEntity, bool>> filter = null, string orderBy = null, int index = , int size = ) where TEntity : class
{
int skipCount = (index - ) * size;
var query = Get(filter, orderBy);
total = query.Count();
query = skipCount > ? query.Skip(skipCount).Take(size) : query.Take(size);
return query.ToList();
} public IQueryable<TEntity> Get<TEntity>(Expression<Func<TEntity, bool>> filter = null, string orderBy = null) where TEntity : class
{
IQueryable<TEntity> query = dbContext.Set<TEntity>();
if (filter != null)
{
query = query.Where(filter);
}
if (!string.IsNullOrEmpty(orderBy))
{
query = query.OrderBy(orderBy);
}
return query.AsQueryable();
} public IQueryable<TEntity> Get<TEntity>(Expression<Func<TEntity, bool>> filter = null, Func<IQueryable<TEntity>, IOrderedQueryable<TEntity>> orderBy = null) where TEntity : class
{
IQueryable<TEntity> query = dbContext.Set<TEntity>();
if (filter != null)
{
query = query.Where(filter);
}
if (orderBy != null)
{
orderBy(query).AsQueryable();
}
return query.AsQueryable();
} #endregion #region 私有方法 private int Save()
{
int effect = ;
if (!this.IsTransaction)
{
effect = dbContext.SaveChanges();
}
return effect;
} /// <summary>
/// 变更上下文管理器(对象)
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="model"></param>
/// <param name="state"></param>
private int ChangeObjectState<TEntity>(TEntity model, EntityState state) where TEntity : class
{
//_context.Configuration.ValidateOnSaveEnabled = false;
dbContext.Entry<TEntity>(model).State = state;
return Save(); } /// <summary>
/// 变更上下文管理器(对象集合)
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="model"></param>
/// <param name="state"></param>
private int ChangeObjectState<TEntity>(IEnumerable<TEntity> model, EntityState state) where TEntity : class
{
if (model == null) return ; //_context.Configuration.AutoDetectChangesEnabled = false;
model.ToList().ForEach(p => dbContext.Entry<TEntity>(p).State = state);
return Save(); } #endregion /// <summary>
/// 执行带参数的sql语句,返回List
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="strsql"></param>
/// <param name="paras"></param>
/// <returns></returns>
public IEnumerable<T> GetList<T>(string strsql, SqlParameter[] paras)
{
return dbContext.Database.SqlQuery<T>(strsql, paras).ToList();
} /// <summary>
/// 执行不带参数的sql语句,返回list
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="strsql"></param>
/// <returns></returns>
public IEnumerable<T> GetList<T>(string strsql)
{
return dbContext.Database.SqlQuery<T>(strsql).ToList();
} /// <summary>
/// 执行带参数的sql语句,返回一个对象
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="strsql"></param>
/// <param name="paras"></param>
/// <returns></returns>
public T GetOneEntity<T>(string strsql, SqlParameter[] paras)
{
return dbContext.Database.SqlQuery<T>(strsql, paras).Cast<T>().First();
} /// <summary>
/// 执行不带参数的sql语句,返回一个对象
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="strsql"></param>
/// <returns></returns>
public T GetOneEntity<T>(string strsql)
{
return dbContext.Database.SqlQuery<T>(strsql).Cast<T>().First();
} public int ExecuteSqlCommand(string sql, params SqlParameter[] paras)
{
if (this.IsTransaction)
{
if (dbContext.Database.CurrentTransaction == null)
{
dbContext.Database.BeginTransaction();
}
}
return dbContext.Database.ExecuteSqlCommand(sql, paras);
} /// <summary>
/// 获取查询数量
/// </summary>
/// <param name="sql"></param>
/// <param name="paras"></param>
/// <returns></returns>
public int GetCount(string sql, SqlParameter[] paras)
{
return dbContext.Database.SqlQuery(typeof(int), sql, paras).Cast<int>().First();
} public void BeginTransaction()
{
this.IsTransaction = true; } public int Commit()
{
int reault = dbContext.SaveChanges();
this.IsTransaction = false;
DbContextTransaction transaction = dbContext.Database.CurrentTransaction;
if (transaction != null)
{
transaction.Commit();
transaction.Dispose();
reault += ;
} return reault;
} public void Rollback()
{
this.IsTransaction = false;
DbContextTransaction transaction = dbContext.Database.CurrentTransaction;
if (transaction != null)
{
transaction.Rollback();
transaction.Dispose();
} } public bool IsTransaction
{
get;
private set;
} public void Dispose()
{
this.Dispose(true);
GC.SuppressFinalize(this);
} public virtual void Dispose(bool disposing)
{
if (!this.disposed)
{
if (disposing)
{
this.dbContext.Dispose();
}
}
this.disposed = true;
}
}
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