Question

这是我的表结构 t_physical_inventory

dte_cycle_count | qty | location

我正在使用以下Linq查询来获得结果

int number = 3;
List<t_physical_inventory> Location = (from c in dc.t_physical_inventories
                where (c.dte_cycle_count == null ||
                ((TimeSpan)(Convert.ToDateTime(c.dte_cycle_count) -
                        (DateTime.Now.Date))).Days > 365) 
                && (c.qty > 0)
                orderby (c.location)
                select c).Take(number).ToList();

问题： 我无法获得dte_cycle_count大于365的记录。

Answer 1

尝试：

int number = 3;
List<t_physical_inventory> Location = null;
        Location = (from c in dc.t_physical_inventories
                    where (c.dte_cycle_count == null 
                       || (DateTime.Now.Date - Convert.ToDateTime(c.dte_cycle_count))
                               ).Days > 365) 
                       && (c.qty > 0)
                    orderby (c.location)
                    select c).Take(number).ToList();

Answer 2

使用TotalDays作为Timespan，1年12天从Days返回12，但TotalDays返回Years * 365 + 12

如果Yahya建议，你应该从较晚的日期减去较早的日期。

Answer 3

时间跨度是否正面？您可以使用Duration-method获取绝对值：

List<t_physical_inventory> Location = null;
Location = (from c in dc.t_physical_inventories
            where (c.dte_cycle_count == null 
            || (c.dte_cycle_count.Value - DateTime.Now.Date).Duration.Days > 365)                  
               && (c.qty > 0)
            orderby (c.location)
            select c).Take(number).ToList();

然而，这对于积极的时间跨度与消极时间相同。最好先从后面的DateTime中减去先前的DateTime。

Answer 4

请注意，如果您希望数据一年，则需要采用不同的方式：

List<t_physical_inventory> Location = null;
Location = (from c in dc.t_physical_inventories
            where (c.dte_cycle_count == null || c.dte_cycle_count.Value < DateTime.Now.AddYears(-1)) && (c.qty > 0)
            orderby (c.location)
            select c).Take(number).ToList();

在linq中选择超过365天的数据

4 个答案: