小编Dav*_*vid的帖子

假设我有一个如下所示的数据库表:

ID          name       salary      start_date              city       region
----------- ---------- ----------- ----------------------- ---------- ------
          1 Jason            40420 1994-02-01 00:00:00.000 New York   W
          2 Robert           14420 1995-01-02 00:00:00.000 Vancouver  N
          3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
          4 Linda            40620 1997-11-04 00:00:00.000 New York   N
          5 David            80026 1998-10-05 00:00:00.000 Vancouver  W
          6 James            70060 1999-09-06 00:00:00.000 Toronto    N
          7 Alison           90620 2000-08-07 00:00:00.000 New York   W
          8 Chris            26020 2001-07-08 00:00:00.000 Vancouver  N
          9 Mary             60020 2002-06-09 00:00:00.000 Toronto    W

是否可以通过start_date降序对其进行排序,然后通过最新的start_date对每个城市组进行排序？例如: …

假设我有一个对象:

public class CustomObj
{
    DateTime Date { get; set; }
    String Name { get; set; }
}

然后,假设我有一个包含20种不同元素的列表.

var stuff = new List<CustomObj>
{
    { Date = DateTime.Now, Name = "Joe" },
    { Date = DateTime.Now.AddDays(1), Name = "Joe2" },
    { Date = DateTime.Now.AddDays(2), Name = "Joe3" },
    { Date = DateTime.Now.AddDays(3), Name = "Joe4" },
    { Date = DateTime.Now.AddDays(4), Name = "Joe5" },
    { Date = DateTime.Now.AddDays(5), Name = "Joe6" },
    { Date = DateTime.Now.AddDays(6), Name = "Joe7" …