Question

How can I employ Linq to select Top value from each group

when I have a code segment like :

var teams = new Team[]
 { 
  new Team{PlayerName="Ricky",TeamName="Australia", PlayerScore=234},
  new Team{PlayerName="Hussy",TeamName="Australia", PlayerScore=134},
  new Team{PlayerName="Clark",TeamName="Australia", PlayerScore=334},

  new Team{PlayerName="Sankakara",TeamName="SriLanka", PlayerScore=34},
  new Team{PlayerName="Udana",TeamName="SriLanka", PlayerScore=56},
  new Team{PlayerName="Jayasurya",TeamName="SriLanka", PlayerScore=433},

 new Team{PlayerName="Flintop",TeamName="England", PlayerScore=111},
 new Team{PlayerName="Hamirson",TeamName="England", PlayerScore=13},
 new Team{PlayerName="Colingwood",TeamName="England", PlayerScore=421}
 };

Desired Result :

Team Name         Player Name     Score

Srilanka          Jayasurya        433

England           colingwood       421

Australia         Clark            334 

Answer 1

My answer is similar to Yuriy’s, but using MaxBy from MoreLINQ, which doesn’t require the comparison to be done by ints:

var query = from player in players
            group player by player.TeamName into team
            select team.MaxBy(p => p.PlayerScore);

foreach (Player player in query)
{
    Console.WriteLine("{0}: {1} ({2})",
        player.TeamName,
        player.PlayerName,
        player.PlayerScore);
}

Note that I’ve changed the type name from “Team” to “Player” as I believe it makes more sense – you don’t start off with a collection of teams, you start off with a collection of players.