Question

我有这个：

List<string> lstRanksOrder = new List<string>() { 
  "Captain", "Lieutenant", "Sergeant", "Corporal Master", 
  "Corporal Senior", "Corporal 1", "Corporal", "Civilian Pilot" };

var emp = test
  .ToList()
  .Select(x => new
     {
       EID = x.IBM,
       Description = string.Format("{0} {1}", x.FirstName, x.LastName),
       Group = x.RPosition
     })
  .AsEnumerable()
  .OrderBy(x => lstRanksOrder.IndexOf(x.Group))
  .ThenBy(x => x.Description)
  .Distinct()
  .ToList();

ThenBy条款工作正常，但有没有办法在LastName之前FirstName更改订单，而不将Description更改为Description = string.Format("{0} {1}", x.LastName, x.FirstName)？

Answer 1

在调用Select扩展名方法之前订购集合：

var emp = test.ToList() .OrderBy(x => lstRanksOrder.IndexOf(x.RPosition)) .ThenBy(x => x.LastName) .ThenBy(x => x.FirstName) .Select(x => new { EID = x.IBM, Description = string.Format("{0} {1}", x.FirstName, x.LastName), Group = x.RPosition }) .Distinct() .ToList();

Answer 2

在调用Distinct扩展方法之前，

Order然后Select集合：

var emp = test.ToList()
.Distinct()
.OrderBy(x => lstRanksOrder.IndexOf(x.RPosition))
.ThenBy(x => x.LastName)
.ThenBy(x => x.FirstName)
.Select(x => new
{
    EID = x.IBM,
    Description = string.Format("{0} {1}", x.FirstName, x.LastName),
    Group = x.RPosition
})

.ToList();

OrderBy和ThenBy与匿名类

2 个答案: