private async Task <TokenBalanceView[]> GetTokenBalances(ulong identifier)
{
var balances = await balanceService.GetAllErc20TokenBalancesAsync(identifier);
var balanceViews = new ConcurrentBag <TokenBalanceView>();
async Task DoWork(TokenBalanceStamp balanceStamp)
{
var course = await coursesService.GetTokenCourse(balanceStamp.Symbol.ToUpperInvariant());
balanceViews.Add(new TokenBalanceView(balanceStamp, course.USD));
}
var tasks = balances.Select(DoWork);
await Task.WhenAll(tasks.ToArray());
return(balanceViews.ToArray());
}