将 SQL 语句转换为 Linq

Question

这是我的示例查询

Select id from employee where id in
(select employeeid from employeecenter where CenterCodeId in 
(select CenterCodeId from employeecenter where employeeid=40))

我们如何使用 Linq 实现上述目标

//Gets all the centerCodeIds allotted to an employee
Session["LoggedUserId"] = 40;
List<int> _centerCodeIds = _cmn.GetCenterEmpwise(Convert.ToInt32(Session["LoggedUserId"]))
                           .Select(x => x.Id).ToList();

//Get all employees having the above centercodids
List<int> _employeeIds = _db.EmployeeCenters
                        .Where(x => _centerCodeIds.Any(cc => x.Id == cc))
                        .Select(x => x.Employee.Id).ToList();

Answer 1

这里是：

List<int> _employeeIds = _db.EmployeeCenters.Where(x => _db.EmployeeCenters
                        .Where(y => y.EmployeeId == 40)
                        .Select(y => y.CenterCodeId)
                        .Contains(x.CenterCodeId))
                      .Select(x => x.EmployeeId)
                      .ToList();

但是你确定你的查询中需要第二个子选择吗？