C# - 为此目的的 LINQ 查询

Question

我有以下带有这些字段的类

public class Account {
     public int Id { get; set; }
     public string Username { get; set; }
     public float Timezone { get; set; }
}

public class Player {
     public int Id { get; set; }
     public virtual Account Account { get; set; }
     public string Team_Name { get; set; }
}

现在假设我有一个名为 Players 的 Player 列表<>，每支球队有 2 名球员，这意味着每个 Team_Name 将重复两次。例如。 Team X 有 Player A 和 Player B，List<> of Player 中的两个条目来表示。

我想要实现的是根据时区将团队相互配对，因为每个团队都有 2 名球员，我应该通过访问 Account.Timezone 球员类中的字段来计算每个团队的平均时区，然后找到另一个最接近平均值的团队使团队与他们相匹配的时区。

Example

Answer 1

假设您有一个像这样的 Match 类:

public class Match
{
    public string Team1 { get; set; }
    public string Team2 { get; set; }
}

你可以用 LINQ 做这样的事情:

var matches =
    Players.GroupBy(player => player.Team_Name) //Group players by team name
        .Select(
            team => //For each team
                new
                {
                    TeamName = team.Key, //Select team name
                    AverageTimezone = //And average time zone
                        team.Average(player => player.Account.Timezone)
                })
        .OrderBy(team => team.AverageTimezone) //Order teams by average time zone
        .Select((team, index) => new {Team = team, Index = index})
        .GroupBy(item => item.Index/2) //Group each two teams together (since the teams are ordered by average timezone, each two teams will have a close timezone)
        .Select(g => g.Select(item => item.Team).ToList())
        .Select(g => new Match
        {
            Team1 = g[0].TeamName,
            Team2 = g[1].TeamName
        })
        .ToList();