Compare records from 2 tables and count for each participant

Question

User-1857885180 posted

I need to count the following for every participant:

Match.HomeGoals/AwayGoals == UserMatch.Homegoals/AwayGoals where Match.Id == UserMatch.MatchId

With my current code i get the sum of goals. I dont know how to proceed.

public class Match
    {
        public Match()
        {
            UserMatches = new HashSet<UserMatch>();
        }

        public int Id { get; set; }
        public int HomeTeamId { get; set; }
        public virtual Team HomeTeam { get; set; }
        public int AwayTeamId { get; set; }
        public virtual Team AwayTeam { get; set; }
        public int? HomeGoals { get; set; }
        public int? AwayGoals { get; set; }
        public DateTime? StartTime { get; set; }

        public virtual ICollection<UserMatch> UserMatches { get; set; }
    }

public class UserMatch
    {
        public int ParticipantId { get; set; }
        public int MatchId { get; set; }
        public virtual Participant Participant { get; set; }
        public virtual Match Match { get; set; }
        public int? HomeGoals { get; set; }
        public int? AwayGoals { get; set; }
    }

public class Participant
    {
        public Participant()
        {
            UserMatches = new HashSet<UserMatch>(); 
        }

        public int Id { get; set; }
        public string Navn { get; set; }
        public int PlayerId { get; set; }
        public virtual Player TopScorer { get; set; }
        //public int TeamId { get; set; }
        //public virtual Team WorldChampion { get; set; }

        public virtual ICollection<UserMatch> UserMatches { get; set; }

    }
 

public ActionResult Index()
        {
            
            var homegoals = db.UserMatches.Where(a => db.Matches.Select(s => s.HomeTeamGoals).Equals(a.HomeGoals)).ToList();
            var awaygoals = db.UserMatches.Where(a => db.Matches.Select(s => s.AwayTeamGoals).Equals(a.AwayGoals)).ToList();
 
            var result = homegoals.Union(awaygoals)
                .GroupBy(s => new {
                    s.ParticipantId,
                    s.Participant.Name
                })
                .Select(s => new ResultatListeViewModel
                {
 
                    Navn = s.Key.Name,
                    TotalScore= s.Sum(r => r.HomeGoals) + s.Sum(r => r.AwayGoals)
 
                }).OrderByDescending(a => a.Poengsum).ToList();
 
            return View(result);
 
        }

<table class="table">
    <tr>
        <th>Name</th>
        <th>Score</th>
    </tr>
    @foreach (var item in Model)
    {
        <tr>
            <td>@item.Name</td>
            <td>@item.TotalScore</td>
        </tr>
    }
 
</table>

Answer 1

User1080785583 posted

I recommond using IEqualityComparer<IMatch>

Create an interface called IMatch that both Match and UserMatch can implement.

Then make use of it like this

using System.Collections.Generic;

public class CompareValuesSample :IEqualityComparer<IMatch> {

public bool Equals(IMatch x, IMatch y){

// here is where you check

// plenty of samples online also

// interface is always a nice route to take for the unknowns

}

public int GetHashCode(IMatch obj){

// implement

}

}

// usage

var homeMatch = new List<HomeMatch>(); // IMatch

var awayMatch = new List<HomeMatch>(); // IMatch

bool equalScore = awayMatch.SequenceEqual(homeMatch, new CompareValuesSample());

// etc