vb.net中的linq和
我需要做一个查询,看起来像是SQL:vb.net中的linq和,vb.net,linq,Vb.net,Linq,我需要做一个查询,看起来像是SQL: SELECT CodProiect, SUM(Valoare) FROM DET WHERE CodProiect = 'cod_pr' GROUP BY CodProiect; 我怎样才能用LINQ写同样的东西 我尝试过这样做: dim gac1 = (From ac1 In t_detalii _ Where ac1!CodProiect = cod_pr1 _ Select ac1!Valoare).
SELECT CodProiect, SUM(Valoare)
FROM DET
WHERE CodProiect = 'cod_pr'
GROUP BY CodProiect;
我怎样才能用LINQ写同样的东西
我尝试过这样做:
dim gac1 = (From ac1 In t_detalii _
Where ac1!CodProiect = cod_pr1 _
Select ac1!Valoare).Sum(Function(ac1) ac1!Valoare)
但是它给了我一个错误“没有为'Double'类型找到默认成员”。您需要选择ac1而不是ac1!Valoare(是属性本身,而不是对应的对象) 编辑 当然,您可以在查询中对其进行分组:
dim gac1 = (From ac1 In t_detalii _
Where ac1!CodProiect = cod_pr1 _
Group By ac1.CodProiect Into ac2
Select ac2.Sum(Function(ac2) ac2!Valoare)
(在这个方向上,我不熟悉vb.net语法,而且我在没有编译器支持atm的情况下编写它。请查看我的编辑,可能会对您有所帮助。
dim gac1 = (From ac1 In t_detalii _
Where ac1!CodProiect = cod_pr1 _
Group By ac1.CodProiect Into ac2
Select ac2.Sum(Function(ac2) ac2!Valoare)