c#当值相同时，对列表进行随机排序

我有一个按分数排序的列表，如下所示：

var orderedList = outcomeRequestModels
    .Where(m => m.Score > 0)
    .OrderByDescending(m => m.Score).ToList();

var t = [{
  name: 'test 1',
  score: 20
}, {
  name: 'test 2',
  score: 30
}, {
  name: 'test 3',
  score: 20
}, {
  name: 'test 4',
  score: 20
}, {
  name: 'test 5',
  score: 20
}, {
  name: 'test 6',
  score: 30
}, {
  name: 'test 7',
  score: 15
}, {
  name: 'test 8',
  score: 20
}, {
  name: 'test 9',
  score: 30
}];

var t = [{
  name: 'test 9',
  score: 30
}, {
  name: 'test 6',
  score: 30
}, {
  name: 'test 2',
  score: 30
}, {
  name: 'test 1',
  score: 20
}, {
  name: 'test 4',
  score: 20
}, {
  name: 'test 5',
  score: 20
}, {
  name: 'test 3',
  score: 20
}, {
  name: 'test 8',
  score: 20
}, {
  name: 'test 7',
  score: 15
}];

var t = [{
  name: 'test 6',
  score: 30
}, {
  name: 'test 2',
  score: 30
}, {
  name: 'test 9',
  score: 30
}, {
  name: 'test 8',
  score: 20
}, {
  name: 'test 4',
  score: 20
}, {
  name: 'test 5',
  score: 20
}, {
  name: 'test 1',
  score: 20
}, {
  name: 'test 3',
  score: 20
}, {
  name: 'test 7',
  score: 15
}];

我想做的是，随机选择列表中得分相同的项目。 因此，如果我有这样一个项目列表：

var orderedList = outcomeRequestModels
    .Where(m => m.Score > 0)
    .OrderByDescending(m => m.Score).ToList();

var t = [{
  name: 'test 1',
  score: 20
}, {
  name: 'test 2',
  score: 30
}, {
  name: 'test 3',
  score: 20
}, {
  name: 'test 4',
  score: 20
}, {
  name: 'test 5',
  score: 20
}, {
  name: 'test 6',
  score: 30
}, {
  name: 'test 7',
  score: 15
}, {
  name: 'test 8',
  score: 20
}, {
  name: 'test 9',
  score: 30
}];

var t = [{
  name: 'test 9',
  score: 30
}, {
  name: 'test 6',
  score: 30
}, {
  name: 'test 2',
  score: 30
}, {
  name: 'test 1',
  score: 20
}, {
  name: 'test 4',
  score: 20
}, {
  name: 'test 5',
  score: 20
}, {
  name: 'test 3',
  score: 20
}, {
  name: 'test 8',
  score: 20
}, {
  name: 'test 7',
  score: 15
}];

var t = [{
  name: 'test 6',
  score: 30
}, {
  name: 'test 2',
  score: 30
}, {
  name: 'test 9',
  score: 30
}, {
  name: 'test 8',
  score: 20
}, {
  name: 'test 4',
  score: 20
}, {
  name: 'test 5',
  score: 20
}, {
  name: 'test 1',
  score: 20
}, {
  name: 'test 3',
  score: 20
}, {
  name: 'test 7',
  score: 15
}];

我希望它的顺序如下：

var orderedList = outcomeRequestModels
    .Where(m => m.Score > 0)
    .OrderByDescending(m => m.Score).ToList();

var t = [{
  name: 'test 1',
  score: 20
}, {
  name: 'test 2',
  score: 30
}, {
  name: 'test 3',
  score: 20
}, {
  name: 'test 4',
  score: 20
}, {
  name: 'test 5',
  score: 20
}, {
  name: 'test 6',
  score: 30
}, {
  name: 'test 7',
  score: 15
}, {
  name: 'test 8',
  score: 20
}, {
  name: 'test 9',
  score: 30
}];

var t = [{
  name: 'test 9',
  score: 30
}, {
  name: 'test 6',
  score: 30
}, {
  name: 'test 2',
  score: 30
}, {
  name: 'test 1',
  score: 20
}, {
  name: 'test 4',
  score: 20
}, {
  name: 'test 5',
  score: 20
}, {
  name: 'test 3',
  score: 20
}, {
  name: 'test 8',
  score: 20
}, {
  name: 'test 7',
  score: 15
}];

var t = [{
  name: 'test 6',
  score: 30
}, {
  name: 'test 2',
  score: 30
}, {
  name: 'test 9',
  score: 30
}, {
  name: 'test 8',
  score: 20
}, {
  name: 'test 4',
  score: 20
}, {
  name: 'test 5',
  score: 20
}, {
  name: 'test 1',
  score: 20
}, {
  name: 'test 3',
  score: 20
}, {
  name: 'test 7',
  score: 15
}];

如果我再看一遍，它会像这样改变顺序：

var orderedList = outcomeRequestModels
    .Where(m => m.Score > 0)
    .OrderByDescending(m => m.Score).ToList();

var t = [{
  name: 'test 1',
  score: 20
}, {
  name: 'test 2',
  score: 30
}, {
  name: 'test 3',
  score: 20
}, {
  name: 'test 4',
  score: 20
}, {
  name: 'test 5',
  score: 20
}, {
  name: 'test 6',
  score: 30
}, {
  name: 'test 7',
  score: 15
}, {
  name: 'test 8',
  score: 20
}, {
  name: 'test 9',
  score: 30
}];

var t = [{
  name: 'test 9',
  score: 30
}, {
  name: 'test 6',
  score: 30
}, {
  name: 'test 2',
  score: 30
}, {
  name: 'test 1',
  score: 20
}, {
  name: 'test 4',
  score: 20
}, {
  name: 'test 5',
  score: 20
}, {
  name: 'test 3',
  score: 20
}, {
  name: 'test 8',
  score: 20
}, {
  name: 'test 7',
  score: 15
}];

var t = [{
  name: 'test 6',
  score: 30
}, {
  name: 'test 2',
  score: 30
}, {
  name: 'test 9',
  score: 30
}, {
  name: 'test 8',
  score: 20
}, {
  name: 'test 4',
  score: 20
}, {
  name: 'test 5',
  score: 20
}, {
  name: 'test 1',
  score: 20
}, {
  name: 'test 3',
  score: 20
}, {
  name: 'test 7',
  score: 15
}];

有人知道我是如何做到这一点的吗？

您可以通过在任意指定的唯一值上“断开领带”来随机化：

var orderedList = outcomeRequestModels
    .Select(m => new {Model = m, RandomId = Guid.NewGuid()})
    .Where(m => m.Model.Score > 0)
    .OrderByDescending(m => m.Model.Score)
    .ThenBy(m => m.RandomId)
    .Select(m => m.Model)
    .ToList();

当然，这不是真正的随机性，但会给人一种相当随意的感觉。相同的方法可用于

随机

的实例，无需太多更改：

var rnd = new Random();
var orderedList = outcomeRequestModels
    .Select(m => new { Model = m, RandomId = rnd.Next() })
    .Where(m => m.Model.Score > 0)
    .OrderByDescending(m => m.Model.Score)
    .ThenBy(m => m.RandomId)
    .Select(m => m.Model)
    .ToList();

---

击败它-但在另一个答案上略有变化，以帮助ORM评论

像这样的怎么样

var rnd = new Random();

var orderedList = models
    .Where(m => m.Score > 0)
    .AsEnumerable()    // Optional - This should alleviate the ORM comment in the previous answer
    .Select(m => new { m.Name, m.Score, Rand = rnd.Next() })
    .OrderByDescending(m => m.Score).ThenBy(m => m.Rand)
    .Select(m => new { m.Name, m.Score })  // Optional
    .ToList();

---

我认为您可以执行如下操作：

var orderedList=outcomeRequestModels.Where（m=>m.Score>0）、OrderByDescending（m=>m.Score）、OrderBy（x=>Guid.NewGuid（））.ToList（）

@Steve Guid是唯一的，不是随机的，也不是一个合适的随机性来源。@Steve您需要

然后通过
，并且您还希望预先将相同的
Guid
与每个记录关联，以避免在排序记录时出现不一致。@DasLinkedIn快速阅读Linq2Objects
EnumerableSorter
（OrderBy的业务端）看起来它在进行任何排序之前构建了一个排序键数组，而排序中使用的正是这个数组。当然，这是一个实现细节，所以可能最好不要过于依赖这种行为。@spender很高兴知道，非常感谢！…尽管@Servy在上面关于GUID是唯一的而不是rando的评论m仍然是相关的。在OPs的情况下可能不相关，但如果您使用
Random
，那么您将很难将其用于ORM（即EF）@在我的书中，Servy是一个无可争议的吹毛求疵的拥护者，所以在某个时候，我不再关注他非常重要的评论。