Linq orderby使用自定义比较器进行两列排序

Question

List<MyObject> objects = (from a in alist
    join b in blist on a.ID equals b.ID
    where a.Number != 4
    orderby b.Rank, a.CustomField
    select a).ToList();

这是我的查询，我想为CustomField属性使用自定义Comparer。有没有办法以双场顺序执行此操作？

我能够做到这一点：

List<MyObject> objects = objects.OrderBy(a => a.CustomField, new MyComparer<object>())

但是我需要它按s.Rank和a.CustomField排序。

Answer 1

将OrderBy()与ThenBy()一起用于您的自定义比较器。

// I'm pretty sure it is not possible to specify
// your custom comparer within a query expression
List<MyObject> objects = (from a in alist
                          join b in blist on a.ID equals b.ID
                          where a.Number != 4
                          select new { a, b })
                         .OrderBy(o => o.b.Rank, new MyRankComparer())
                         .ThenBy(o => o.a.CustomField, new MyComparer<object>())
                         .Select(o => o.a)
                         .ToList();

Answer 2

试试这个：

List<MyObject> objects = objects
    .OrderBy(a => a.Rank)
    .ThenBy(a => 
        a.CustomField, new MyComparer<object>()
    ).ToList();

首先按Rank字段排序，然后按CustomField排序自定义比较器。