Question

I have two methods which are very close, and want to create one method that I can call to keep my code DRY

public IEnumerable<HighScoreViewModel> GetNightlyHighScores()
{
    lock (_Key)
    {
        //return GetHighScores(x => x.NightlyHighScore);

        return _allPlayers
            .OrderByDescending(x => x.NightlyHighScore)
            .Take(8)
            .Select(x=> new HighScoreViewModel
            {
                Points = x.NightlyHighScore,
                PointsText = "FG: " + x.NightlyHighScore,
                ImageUrl = x.Facebook.SmallImageUrl,
                DisplayName = x.DisplayName,
            }).ToList();
    }
}

public IEnumerable<HighScoreViewModel> GetBestHighScores()
{
    lock (_Key)
    {
        //return GetHighScores(x => x.BestHighScore);

        return _allPlayers
            .OrderByDescending(x => x.BestHighScore)
            .Take(8)
            .Select(x => new HighScoreViewModel
            {
                Points = x.BestHighScore,
                PointsText = "FG: " + x.BestHighScore,
                ImageUrl = x.Facebook.SmallImageUrl,
                DisplayName = x.DisplayName,
            }).ToList();
    }
}

I’m close to something, but can’t figure out the bits marked “magic”

public IEnumerable<HighScoreViewModel> GetHighScores<TKey>(Func<Player, TKey> highscore)
{
    return _allPlayers
        .OrderByDescending(highscore)
        .Take(8)
        .Select(x => new HighScoreViewModel
        {
            // Magic?
            //Points = x.BestHighScore,
            PointsText = "FG: " + x.BestHighScore,
            //ImageUrl = x.Facebook.SmallImageUrl,
            DisplayName = x.DisplayName,
        }).ToList();
}

Answer 1

Since BestHighScore and NightlyHighScore have the same type, you should be able to do:

public IEnumerable<HighScoreViewModel> GetHighScores(Func<Player, double> highscore)
{
    return _allPlayers
        .OrderByDescending(highscore)
        .Take(8)
        .Select(x => new HighScoreViewModel
        {
            // Magic?
            Points = highScore(x),
            PointsText = "FG: " + x.BestHighScore,
            //ImageUrl = x.Facebook.SmallImageUrl,
            DisplayName = x.DisplayName,
        }).ToList();
}

highscore should return whatever the real type of Points is.