public virtual IQueryable <T> GetEntitiesForPaging <T>(int pageNumber, int pageSize, Expression <Func <T, string> > orderName, string sortOrder, Expression <Func <T, bool> > exp) where T : class
{
using (DbEntities db = new DbEntities())
{
if (sortOrder == "asc") //升序排列
{
return(db.Set <T>().Where(exp).OrderBy(orderName).Skip((pageNumber - 1) * pageSize).Take(pageSize));
}
else
{
return(db.Set <T>().Where(exp).OrderByDescending(orderName).Skip((pageNumber - 1) * pageSize).Take(pageSize));
}
}
}
public virtual T GetEntity <T>(Expression <Func <T, bool> > exp) where T : class
{
using (DbEntities db = new DbEntities())
{
return(db.Set <T>().Where(exp).SingleOrDefault());
}
}
public virtual int GetEntitiesCount <T>(Expression <Func <T, bool> > exp) where T : class
{
using (DbEntities db = new DbEntities())
{
return(db.Set <T>().Where(exp).Count());
}
}
public virtual void Delete <T>(T entity, bool isSubmit) where T : class
{
if (isSubmit && _dbEntities == null)
{
using (DbEntities db = new DbEntities())
{
var obj = db.Set <T>();
if (entity != null)
{
obj.Attach(entity);
db.Entry(entity).State = System.Data.EntityState.Deleted;
obj.Remove(entity);
db.SaveChanges();
}
}
}
else
{
_dbEntities.Set <T>().Attach(entity);
_dbEntities.Entry(entity).State = System.Data.EntityState.Deleted;
_dbEntities.Set <T>().Remove(entity);
_dbEntities.SaveChanges();
}
}
/// <summary>
/// 根据条件获取数据实体集合
/// </summary>
/// <typeparam name="T">实体类型</typeparam>
/// <param name="exp">条件表达式</param>
/// <param name="useBaseContext">是否使用类基础的context，以达到延迟加载的目的</param>
/// <returns></returns>
public virtual IQueryable <T> GetEntities <T>(Expression <Func <T, bool> > exp, bool useBaseContext = false) where T : class
{
if (useBaseContext)
{
return(_dbEntities.Set <T>().Where(exp));
}
using (DbEntities db = new DbEntities())
{
return(db.Set <T>().Where(exp));
}
}
public virtual T Insert <T>(T entity, bool isSubmit) where T : class
{
if (isSubmit && _dbEntities == null)
{
using (DbEntities db = new DbEntities())
{
var obj = db.Set <T>();
T result = obj.Add(entity);
db.SaveChanges();
return(result);
}
}
else
{
_dbEntities.Entry(entity);
T result = _dbEntities.Set <T>().Add(entity);
_dbEntities.SaveChanges();
return(result);
}
}