原文：https://blog.csdn.net/pan_junbiao/article/details/79968226

 
    //歸集每個部門資訊
    List<DeptInfo> deptList = (from emp in empList
                                where emp.Status == "在職"            //篩選“在職”員工     
                                orderby emp.DeptID ascending          //按“部門ID”排序
                                group emp by new
 
                      //按“部門ID”和“部門名稱”分組
                                {
                                    emp.DeptID,
                                    emp.DeptName
                                }
                                into g
                                select new DeptInfo()
                                {
                                    DeptID 
 
= g.Key.DeptID,
                                    DeptName = g.Key.DeptName,
                                    EmplayeeCount = g.Count(),          //統計部門員工數量
                                    WageSum = g.Sum(a => a.Wage),       //統計部門工資總額
                                    WageAvg = g.Average(a => a.Wage),   //
 
統計部門平均工資
                                    EmplayeeList = (from e in g         //歸集部門員工列表
                                                    select new Emplayee()
                                                    {
                                                        EmpID = e.EmpID,
                                                        EmpName = e.EmpName
                                                    }
                                                    ).ToList()
 
                                }).ToList();