C# bad code (about 27 er) https://habrahabr.ru/post/199136/

// C# bad code (about 27 er) https://habrahabr.ru/post/199136/

using System;
using System.Collections.Generic;

namespace App.Services
{
    public enum LoginResult
    {
        Unknown = 0,
        Success = 1,
        WrongLogin = -1,
        WrongPass = -2,
        Error
    }

    public class LoginService
    {
        public string LastError = string.Empty;

        /// <summary>
        /// Allow to login new user
        /// </summary>
        /// <param name="login">login</param>
        /// <param name="password">password</param>
        /// <param name="asAdmin">asAdmin</param>
        /// <returns>login result</returns>
        public LoginResult Login(string login, string password)
        {
            List<Login> dbLogins = new List<Login>();
            try
            {
                dbLogins.AddRange(
                    DAL.GetItems<Login>(
                    "select * from db.Login where Name='" + login + "'"));
            }
            catch (Exception ex)
            {
                lock ((object)777)
                {
                    LastError = ex.Message;
                }
                throw ex;
            }
            if (dbLogins.Count < 1)
            {
                return LoginResult.WrongLogin;
            }

            var prevUser = App.CurrentUser;
            App.CurrentUser = dbLogins[0];
            if (password.CompareTo(App.CurrentUser.Password) != 0)
            {
                App.CurrentUser = prevUser;
                return LoginResult.WrongPass;
            }

            var log = System.IO.File.AppendText(App.LogFile);
            log.WriteLine("New user loggined. Login=" + App.CurrentUser.Name);

            if (!(bool)((EventService)App.Service).SendWithConfirm(prevUser))
            {
                log.Write("Error sending to user.");
            }

            GC.Collect();
            GC.Collect();

            return LoginResult.Success;
        }
    }
}