factorypattern.cs

public class AccountFactory : IAccountFactory
{
    public AccoutType GetAccoutType(string accountName)
    {
        if (accountName.Equals("SAVINGS", StringComparison.OrdinalIgnoreCase))
        {
            return new SavingsAccount();
        }
        else if (accountName.Equals("CURRENT", StringComparison.OrdinalIgnoreCase))
        {
            return new CurrentAccount();
        }
        else
        {
            throw new ArgumentException("Invalid account name");
        }
    }
}