c# - sql 到 linq 查询转换

Question

我尝试将 SQL 转换为 LINK 查询

我试试这个

SQL 查询

Select name, count(*) from tblVehicles
WHERE MID = 23065 and name<> '' Group By name

LINQ 查询

var re = (from vehvoila in DB.tblVehicles
             where vehvoila.MID='23065' && vehvoila.name
             group vehvoila by new{vehvoila.name} into g
             select new
             {
                 g.Key.name,
                 cnt=g.Select(t=>t.name).Count()
             });

我如何在 LINQ 中使用 <> ？

Answer 1

对你有用的是

where vehvoila.MID == "23065" && !(vehvoila.name == null || vehvoila.name == "")

或者只是

where vehvoila.MID == "23065" && vehvoila.name != ""

String.IsNullOrEmpty 在 Linq-SQL 中不受支持:

Method 'Boolean IsNullOrEmpty(System.String)' has no supported translation to SQL.