我有一个需要在整个地方重用的查询,我需要改变哪个属性/列用于连接. 我希望能做的是：query = RestrictByProp(query, x=>x.ID);极简化的RestrictByProp()可能是*：private static IQueryable<Role> RestrictByProp(IQueryable<Role> query, Func<Role, int> selector) {return query.Where(x => selector(x) == 1); }问题是即使这个简单的实现也会导致运行时异常：Method 'System.Object DynamicInvoke(System.Object[])' has no ...
SQL、LINQ、Lambda 三种用法颜色注释： SQL LinqToSql Lambda QA1、 查询Student表中的所有记录的Sname、Ssex和Class列。select sname,ssex,class from studentLinq: from s in Students select new { s.SNAME, s.SSEX, s.CLASS }Lambda: Students.Select( s => new { SNAME = s.SNAME,SSEX = s.SSEX,CLASS = s.CLASS }) 2、 查询教师所有的单位即不重复的Depart列。select distinct d...
SQLLINQ LambdaSELECT *FROM HumanResources.Employee from e in Employees select e Employees .Select (e => e) SELECT e.LoginID, e.JobTitle FROM HumanResources.Employee AS e from e in Employees select new {e.LoginID, e.JobTitle} Employees.Select ( e => new { LoginID = e.LoginID, JobTitle = e.JobTitle } ) SELECT e.LoginID AS ID, e.JobTitle AS Title FROM Hum...