Question

我想根据字段（dateType）的a值向查询中添加其他where子句

如果dateType = 1，则（StartDate <= Now && EndDate => Now）//特定日期范围
如果dateType = 2，则（时段=> Now.Month && Year => Now.Year）//月
如果dateType = 3，那么（Period => Now.Month / 4）//季度

我尝试了三元运算符，但这不起作用，这是我查询的开始。

        var query = from e in context.Events
            join c in context.EventCategories on e.CategoryId equals c.CategoryId
            join o in context.Owners on e.OwnerId equals o.OwnerId
            where !e.IsDeleted 
                  && (e.DateType == 1 ? (e.StartDateTimeUtc <= DateTime.UtcNow && e.EndDateTimeUtc =>DateTime.UtcNow))

使用EF Core 2.2

Answer 1

最后的答案，感谢Gert Arnold在对OP的评论中提供指导

    var query = from e in context.Events
                    join c in context.EventCategories on e.CategoryId equals c.CategoryId
                    join o in context.Owners on e.OwnerId equals o.OwnerId
                    where !e.IsDeleted && (e.DateType == 1 && e.StartDateTimeUtc <= DateTime.UtcNow && e.EndDateTimeUtc >= DateTime.UtcNow) //specific date
                                           || (e.DateType == 2 && e.Period >= DateTime.UtcNow.Month && e.Year >= DateTime.UtcNow.Year) // month
                                           || (e.DateType == 3 && e.Period >= DateTime.UtcNow.Month / 3 && e.Year >= DateTime.UtcNow.Year) //quarter

EF Core-根据字段值添加条件

1 个答案: