using System;

​

public class Program

{

    public static void Main()

    {

        IWindowsUser adUser = new IWindowsUser();

        adUser.DomainLoginName = "Pugnet\\TCulter";

        adUser.UserPrincipalName = "TCulter@Pugnet.com";

        string personLoginName = "TCulter@Pugnet.com";

        // START TESTS

        Console.WriteLine("TEST-1: Compare TCulter@Pugnet - TCulter@Pugnet");

        bool domainMatches = ValidateAdUserDomainMatchesPersonLoginName(adUser, personLoginName);

        if (!domainMatches)

        {

            Console.WriteLine("No match");

        }

        else

        {

            Console.WriteLine("Match");

        }

​

        personLoginName = "Pugnet\\TCulter";

        Console.WriteLine("TEST-2: Compare Pugnet\\TCulter - TCulter@Pugnet");

        domainMatches = ValidateAdUserDomainMatchesPersonLoginName(adUser, personLoginName);

        if (!domainMatches)

        {

            Console.WriteLine("No match");

        }

        else

        {

            Console.WriteLine("Match");

        }

    }

​

    private static bool ValidateAdUserDomainMatchesPersonLoginName(IWindowsUser adUser, string personLoginName)

    {

        var domainMatches = true;

        string personAdUserName;

        string personAdDomainName;

        Username.Split(personLoginName, out personAdUserName, out personAdDomainName);

        var personLoginNameIsSlashFormat = personLoginName.Contains("\\");

        var personLoginNameIsAtFormat = personLoginName.Contains("@");

        if ((personLoginNameIsSlashFormat && personLoginName.ToUpperInvariant() != adUser.DomainLoginName.ToUpperInvariant()) || (personLoginNameIsAtFormat && (adUser.UserPrincipalName == null || (adUser.UserPrincipalName != null && adUser.UserPrincipalName.ToUpperInvariant() != personLoginName.ToUpperInvariant()))))

        {

            domainMatches = false;

        }

​

        return domainMatches;

    }

​

    private class IWindowsUser

    {

        public string DomainLoginName { get; set; }

​

        public string UserPrincipalName { get; set; }

    }

}

​

public static class Username

{

    public static void Split(string username, out string principal, out string authority)

    {

        if (username == null)

        {

            throw new ArgumentNullException("username");

        }

​

        string[] parts = username.Split(Seperators.All);

        if (parts.Length == 1)

        {

            // With only one part we assume the user name only contains a

            // principal and no authority.

            authority = null;

            principal = parts[0];

        }

        else if (parts.Length == 2)

        {

            // A simple way to determine whether the user name is in the

            // SamCompatible or PrincipalAuthority format: check whether it

            // has the appropriate separator.

            if (username.IndexOf(Seperators.Internet) != -1)

            {

                authority = parts[1];

                principal = parts[0];

            }

            else

            {

                authority = parts[0];

                principal = parts[1];

            }

        }

        else

        {

            // This just means that there are one too many '@' or '\'

            // characters in the user name. There can only be one.

            throw new ArgumentOutOfRangeException("username", "Login name can contain no more than one @ or \\ character.");

        }

    }

​

    private static class Seperators

    {

        /// <summary>

        /// </summary>

        public static char[] All

        {

            get

            {

                char[] all = {WindowsNT, Internet};

                return all;

            }

        }

​

        /// <summary>

        /// </summary>

        public static char Internet

        {

            get

            {

                return '@';

            }

        }

​

        /// <summary>

        /// </summary>

        public static char WindowsNT

        {

            get

            {

                return '\\';

            }

        }

    }

}