entity异常　不允许启动新事务，因为有其他线程正在该会话中运行。

代码：

IOrderedQueryable<TOHOSPITAL_TBL> tb = ent.TOHOSPITAL_TBL.Where(record =>

(record.TOHOSPITAL_STATE_TYPE_TBL.VALUE == (int)ToHospitolState.treatment) ||

(record.TOHOSPITAL_STATE_TYPE_TBL.VALUE == (int)ToHospitolState.Clinic)).

OrderByDescending(record => record.TOHOSPITAL_TIME);

foreach (TOHOSPITAL_TBL tohospotal in tb)

{

if (!tohospotal.TOHOSPITAL_STATE_TYPE_TBLReference.IsLoaded)

{

tohospotal.TOHOSPITAL_STATE_TYPE_TBLReference.Load();

}

ChangeState(tohospotal);

　　 ent.SaveChanges();

}

原因IOrderedQueryable<TOHOSPITAL_TBL> tb还在查询中，调用ent.SaveChanges();产生的。

ent.SaveChanges();提出即可

代码：

IOrderedQueryable<TOHOSPITAL_TBL> tb = ent.TOHOSPITAL_TBL.Where(record =>

(record.TOHOSPITAL_STATE_TYPE_TBL.VALUE == (int)ToHospitolState.treatment) ||

(record.TOHOSPITAL_STATE_TYPE_TBL.VALUE == (int)ToHospitolState.Clinic)).

OrderByDescending(record => record.TOHOSPITAL_TIME);

foreach (TOHOSPITAL_TBL tohospotal in tb)

{

if (!tohospotal.TOHOSPITAL_STATE_TYPE_TBLReference.IsLoaded)

{

tohospotal.TOHOSPITAL_STATE_TYPE_TBLReference.Load();

}

ChangeState(tohospotal);

}

ent.SaveChanges();