在 LINQ 中对 IEnumerable 进行排序答案

【问题标题】：Sorting an IEnumerable in LINQ在 LINQ 中对 IEnumerable 进行排序
【发布时间】：2012-09-03 13:34:41
【问题描述】：

如何对给定的示例进行排序。

        IEnumerable<extra> eList = new List<extra>()
        {
            new extra{ id = 1, text = "a"},
            new extra{ id = 2, text = "g"},
            new extra{ id = 3, text = "i"},
            new extra{ id = 4, text = "e"},
            new extra{ id = 5, text = "f"},
            new extra{ id = 6, text = "d"},
            new extra{ id = 7, text = "c"},
            new extra{ id = 8, text = "h"},
            new extra{ id = 9, text = "b"}
        };

        IEnumerable<sample> sam = new List<sample>()
        {
            new sample{ id = 1, name = "sample 1", list = new List<int>{1,5,6}},
            new sample{ id = 2, name = "sample 1", list = new List<int>{2,9}},
            new sample{ id = 3, name = "sample 1", list = new List<int>{8,3,7}},
            new sample{ id = 4, name = "sample 1", list = new List<int>{3,4,8}},
            new sample{ id = 5, name = "sample 1", list = new List<int>{1,5,7}},
            new sample{ id = 6, name = "sample 1", list = new List<int>{6,9,7}}
        };

我有这段代码可以对示例列表进行排序并将其加入到上面的额外对象中。

           var s2 = (from d1 in sam
                  select new
                  {
                      name = d1.name,
                      id = d1.id,
                      list =
                      (
                         from d2 in d1.list
                         join e in eList on d2 equals e.id
                         select new {  
                             id = d2, text = e.text
                         }
                      ).OrderBy(item => item.text.FirstOrDefault())
                  });

上面的代码运行良好，它连接了两个数据并对列表的值进行了排序。但我想要的是's2'上方的输出将按'list.text'的'list'值再次排序。

所以上面可能的输出必须是：

        { id = 1, name = "sample 1", list = {'a','f','d'}},         
        { id = 5, name = "sample 1", list = {'a','f','c'}},
        { id = 2, name = "sample 1", list = {'g','b'}},
        { id = 4, name = "sample 1", list = {'i','e','h'}},
        { id = 6, name = "sample 1", list = {'d','b','c'}},
        { id = 3, name = "sample 1", list = {'h','i','c'}},

这在 LINQ 中可行吗？

谢谢

【问题讨论】：

标签： c# linq linq-to-objects

【解决方案1】：

var newsam = sam.Select(s => new
                 {
                   id = s.id,
                   name = s.name,
                   list = s.list
                           .Select(l => eList.FirstOrDefault(e => e.id == l).text)
                           .OrderBy(e => e)
                           .ToList()
                 }
                ).OrderBy(s => s.list.FirstOrDefault())
                 .ToList();

编辑

因此，内部列表按 eList 的文本值排序；并且外部列表按内部列表的第一个元素排序

编辑

          var s2=(from d1 in sam
                  select new
                  {
                      name = d1.name,
                      id = d1.id,
                      list =
                      (
                         from d2 in d1.list
                         join e in eList on d2 equals e.id
                         select e.text
                      ).OrderBy(item => item).ToList()
                  }).OrderBy(item => item.list.FirstOrDefault());

【讨论】：