Get Month name from month number

For short month names use:

string monthName = new DateTime(2010, 8, 1)
    .ToString("MMM", CultureInfo.InvariantCulture);

For long/full month names for Spanish (“es”) culture:

string fullMonthName = new DateTime(2015, i, 1).ToString("MMMM", CultureInfo.CreateSpecificCulture("es"));