Discord.net | How can I turn the user ID's that belong to people in my database to usernames which I can use for my leaderboard?

Question

I'm making a leaderboard for the leveling system my Discord bot has. The list will make a list of the people with most XP and order them from highest to lowest amount. I have already achieved this goal, but I can only show to user's ID next to their XP amount in the leaderboard. How can I turn this user ID into a username?

foreach (ulong n in DbContext.Experiences.OrderByDescending(x => 
x.XP).Select(x => x.ID))
{
    Context.Guild.GetUser(n).ToString()
}

var leaderboard = string.Concat(DbContext.Experiences.OrderByDescending(x => 
x.XP).Select(x => $"Level {x.LevelNumber} with {x.XP} xp 
    {//username must be here}\n"));

await ReplyAsync(leaderboard.ToString());

Answer 1

See comments in code:

//What exactly is this for loop meant to do? 
//You appear to be getting a user based on ID and doing nothing with that value.
//This should be removed
foreach (ulong n in DbContext.Experiences.OrderByDescending(x => 
x.XP).Select(x => x.ID))
{
   //While this is how to get a user by ID, you aren't actually doing anything with this once it's retrieved.
    Context.Guild.GetUser(n).ToString()
}

//You can simply fetch the username here, given that you have access to the ID
var leaderboard = string.Concat(DbContext.Experiences.OrderByDescending(x => 
x.XP).Select(x => $"Level {x.LevelNumber} with {x.XP} xp 
    {//username must be here}\n"));

await ReplyAsync(leaderboard.ToString());

Your modified code should look something like:

var leaderboard = string.Join("\n", DbContext.Experiences
                                             .OrderByDescending(x => x.XP)
                                             .Select(x => $"Level {x.LevelNumber} with {x.XP} xp {Context.Guild.GetUser(x.ID).ToString()}"));
await ReplyAsync(leaderboard);

NOTE: I've replaced string.Concat with string.Join as it's a more efficient String building method.