/// <summary>
/// 获取分页列表
/// </summary>
/// <param name="pagetion"></param>
/// <returns></returns>
public virtual IQueryable <TEntity> GetList(Pagetion pagetion)
{
if (pagetion == null)
{
throw new ArgumentNullException();
}
return(GetList(pagetion, false));
}
/// <summary>
/// 获取筛选结果后的分页列表，按照CreateTime asc排序
/// </summary>
/// <param name="whereLamb">过滤表达式</param>
/// <param name="pagetion"></param>
/// <param name="orderByAscCreateTime"></param>
/// <returns></returns>
public virtual IQueryable <TEntity> GetList(Expression <Func <TEntity, bool> > whereLamb, Pagetion pagetion, bool orderByAscCreateTime)
{
if (pagetion == null)
{
throw new ArgumentNullException("参数不能为空！");
}
Type typeEntity = typeof(TEntity);
IQueryable <TEntity> entities = null;
if (whereLamb == null)
{
entities = GetList();
}
else
{
entities = GetList(whereLamb);
}
#region 动态构建orderby
string strOrderby = orderByAscCreateTime ? "OrderBy" : "orderbydescending";
//创建一个参数c
ParameterExpression param =
Expression.Parameter(typeof(TEntity), "t");
MethodCallExpression orderByCallExpression = null;
if (typeEntity.GetProperty(BaseFields.CreateTime) != null)
{
orderByCallExpression = Expression.Call(
typeof(Queryable), strOrderby,
new Type[] { typeof(TEntity), typeof(DateTime) },
Expression.Constant(entities),
Expression.Lambda(Expression.Property
(param, BaseFields.CreateTime), param));
}
else if (typeEntity.GetProperty(BaseFields.Sort) != null)
{
orderByCallExpression = Expression.Call(
typeof(Queryable), "OrderBy",
new Type[] { typeof(TEntity), typeof(int) },
Expression.Constant(entities),
Expression.Lambda(Expression.Property
(param, BaseFields.Sort), param));
}
if (orderByCallExpression == null)
{
throw new Exception("目标表至少要有CreateTime 获取Sort作为排序字段");
}
#endregion
//生成动态查询
IQueryable <TEntity> query = entities
.Provider.CreateQuery <TEntity>(orderByCallExpression).Skip(pagetion.rows * (pagetion.page - 1)).Take(pagetion.rows);
pagetion.total = entities.Count();
return(query);
}
/// <summary>
/// 获取分页列表，按照CreateTime asc排序
/// </summary>
/// <param name="pagetion"></param>
/// <param name="orderbyAscCreateTime">按照CreateTime 顺序排列</param>
/// <returns></returns>
public virtual IQueryable <TEntity> GetList(Pagetion pagetion, bool orderbyAscCreateTime)
{
return(GetList(null, pagetion, orderbyAscCreateTime));
}
