CSHARP

c# entity framework order by array

var countByOtherId = db.EntityToOrder
    .GroupBy(e => e.OtherId)
    .Select(g => new { ID = g.Key, Count = g.Count() })
    .ToDictionary(e => e.ID, e => e.Count);

var other = new Dictionary<long, string>();
int skipCount = startIndex, useCount = 0;
foreach (var e in db.OtherEntity.OrderBy(e => e.Name))
{
    int count;
    if (!countByOtherId.TryGetValue(e.ID, out count)) continue;
    if (skipCount > 0 && other.Count == 0)
    {
        if (skipCount >= count) { skipCount -= count; continue; }
        count -= skipCount;
    }
    other.Add(e.ID, e.Name);
    if ((useCount += count) >= pageSize) break;
}


var entities = db.EntityToOrder
    .Where(e => other.Keys.Contains(e.OtherId))
    .AsEnumerable()
    .Select(e => new EntityToOrder { ID = e.ID, Name = e.Name, 
        OtherId = e.OtherId, OtherName = other[e.OtherId] })
    .OrderBy(e => e.OtherName).ThenBy(e => e.Name)
    .Skip(skipCount).Take(pageSize)
    .ToList();