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API is mixing up data from different devices

I have an API that has devices firing data to it at the same time or within a few milliseconds. What I am finding is that the data is getting mixed up. The data is sent every five minutes (on the clock 05, 10, 15 etc.) I have an execution filter that traps the URL data coming in so I always have a real source, then it goes to the endpoint and then onto processing. For example, there will a be random five minute period missing. When I debug step by step with the missing URL from the execution filter it works fine. By that I mean I take the URL and debug, then it inserts.
In summary, I have device id 1 and device id 2.I will get missing intervals even though, I can see the data has hit the execution filter.
I am assuming that the API is not handling these as separate transactions, but somehow mixing them up together, hence the data missing and the serial numbers appearing in the wrong place, such that data from id 1 is appearing in id 2 vice versa etc.
API End Point:
public class SomeController : ApiController
{
[HttpGet]
[ExecutionFilter]
public async Task<HttpResponseMessage> Get([FromUri] FixedDataModel fdm)
{
var reply = new HttpResponseMessage();
string url = HttpUtility.UrlDecode(HttpContext.Current.Request.QueryString.ToString());
if (url.Contains("timestamp"))
{
reply = TimeSyncValidation.TimeSync;
return reply;
}
else if (!url.Contains("timestamp"))
{
reply = await Task.Run(() => DeviceClass.DeviceApiAsync(fdm, url));
}
return reply;
}
}
Processing class:
namespace API.Services
{
public class DeviceClass
{
private static string serialNumber;
private static byte chk;
private static string channelName, channelReadingNumber, channelValue, queryString, readingDate;
private static int colonPosition, chanCountFrom, equalsPosition;
private static bool checkSumCorrect;
public static HttpResponseMessage DeviceApiAsync(FixedDataModel fdm, string urlQqueryString)
{
Guid guid = Guid.NewGuid();
//ExecutionTrackerHandler.Guid = guid;
//Remove question mark
var q = urlQqueryString;
queryString = q.Substring(0);
var items = HttpUtility.ParseQueryString(queryString);
serialNumber = items["se"];
//Store raw uri for fault finding
var rawUri = new List<RawUriModel>
{
new RawUriModel
{
UniqueId = guid,
RawUri = q,
TimeStamp = DateTime.Now
}
};
//Checksum validation
chk = Convert.ToByte(fdm.chk);
checkSumCorrect = CheckSumValidator.XorCheckSum(queryString, chk);
if (!checkSumCorrect)
{
return ValidationResponseMessage.ResponseHeaders("Checksum");
}
//Create list of items that exist in URL
var urldata = new UrlDataList
{
UrlData = queryString.Split('&').ToList(),
};
var data = new List<UriDataModel>();
//Split the URL string into its parts
foreach (var item in urldata.UrlData)
{
colonPosition = item.IndexOf(":");
chanCountFrom = colonPosition + 1;
equalsPosition = item.LastIndexOf("=");
if (colonPosition == -1)
{
channelName = item.Substring(0, equalsPosition);
channelReadingNumber = "";
channelValue = item.Substring(item.LastIndexOf("=") + 1);
}
else
{
channelName = item.Substring(0, colonPosition);
channelReadingNumber = item.Substring(chanCountFrom, equalsPosition - chanCountFrom);
channelValue = item.Substring(item.LastIndexOf("=") + 1);
if (channelName == "atime" || channelName == "adate")
{
readingDate = DateValidator.CreateDate(channelValue);
}
};
bool nullFlag = false;
if (channelValue == null)
nullFlag = true;
bool missingFlag = false;
if (channelValue == "x") {
missingFlag = true;
channelValue = "0";
}
//Add data to model ready for DB insert.
data.Add(new UriDataModel
{
uid = guid,
SerialNumber = serialNumber,
ChannelName = channelName,
ChannelReadingNumber = channelReadingNumber,
ChannelValue = channelValue.Replace(",", "."),
ReadingDate = readingDate,
TimeStamp = DateTime.Now.ToString("yyyy-MM-dd HH:mm"),
Processed = false,
NullFlag = nullFlag,
MissingFlag = missingFlag
});
};
//Validate dates
var allDates = (from x in data where x.ChannelName.Contains("atime") || x.ChannelName.Contains("adate") select x.ChannelValue).ToList();
bool dateValidation = DateValidator.IsValid(allDates);
if (!dateValidation)
{
return ValidationResponseMessage.ResponseHeaders("Date");
};
//Validate values
var channels = Enum.GetNames(typeof(Channels)).ToList();
List<string> allChannelValues = data.Where(d => channels.Contains(d.ChannelName)).Select(d => d.ChannelValue).ToList();
bool valueValidation = ValueValidator.IsValid(allChannelValues);
if (!valueValidation)
{
return ValidationResponseMessage.ResponseHeaders("Values");
};
//Insert live data
var insertData = DataInsert<UriDataModel>.InsertData(data, "Staging.UriData");
if (!insertData)
{
return ValidationResponseMessage.ResponseHeaders("Sql");
}
var content = "\r\nSUCCESS\r\n";
var reply = new HttpResponseMessage(System.Net.HttpStatusCode.OK)
{
Content = new StringContent(content)
};
return reply;
}
}
}
TIA

You are using global variables and static method to process your data.
Change your method to non-static.
Each DeviceClass worker must update only its own isolated data then push that off back to controller.

C# Value cannot be null. Parameter name: user

In my C# application I use 2 connection strings (application_cs, users_cs). To change these connection strings I use:
private static void SetProviderConnectionString(string connectionString)
{
var connectionStringFieldM =
Membership.Provider.GetType().GetField("_sqlConnectionString",
BindingFlags.Instance | BindingFlags.NonPublic);
var connectionStringFieldR = Roles.Provider.GetType().GetField("_sqlConnectionString",
BindingFlags.Instance | BindingFlags.NonPublic);
var connectionStringFieldP = ProfileManager.Provider.GetType().GetField("_sqlConnectionString",
BindingFlags.Instance | BindingFlags.NonPublic);
connectionStringFieldM.SetValue(Membership.Provider, connectionString);
connectionStringFieldR.SetValue(Roles.Provider, connectionString);
connectionStringFieldP.SetValue(ProfileManager.Provider, connectionString);
}
public static void SetProviderUsers()
{
SetProviderConnectionString(ConfigurationManager.ConnectionStrings["users_cs"].ConnectionString);
}
public static void SetProviderApp()
{
SetProviderConnectionString(ConfigurationManager.ConnectionStrings["application_cs"].ConnectionString);
}
So in my code whenever I want to add a user I do this:
public int CreateUser(int stid, int cid, int usrId, string email, string tel, string mob, string username,
bool create, bool prime)
{
int result = 0;
Guid userid = new Guid();
DALUsers.UserDBDataContext dc = new DALUsers.UserDBDataContext();
DAL.AppDataContext d = new DAL.AppDataContext();
BLL.Security.SetProviderUsers();
if (create) //create the user first
{
string question = "1";
string answer = "1";
bool isAproved = true;
string password = System.Web.Security.Membership.GeneratePassword(8, 2);
MembershipCreateStatus cs = new MembershipCreateStatus();
MembershipUser newUser = Membership.CreateUser(username, password, email, question, answer, isAproved, out cs);
Membership.UpdateUser(newUser);
Roles.AddUserToRole(username, "User_x");
if (cs == MembershipCreateStatus.Success)
{
result = 1;
}
else
X.MessageBox.Info("Error", "Cannot create user due to :" + cs.ToString(), UI.Danger).Show();
}
//at this point we have the user created either way.
// return userid;
var id = (from i in dc.aspnet_Users where i.UserName.CompareTo(username) == 0 select i.UserId);
if (id.Count() == 1)
{
userid = id.First();
bool contin = true;
var fulname = (from i in dc.Clients where i.id == usrId select i).First();
if (String.IsNullOrEmpty(fulname.Mobile)) fulname.Mobile = mob;
fulname.Email = email;
fulname.ModifiedBy = HttpContext.Current.User.Identity.Name;
fulname.ModifiedDate = DateTime.Now;
dc.SubmitChanges();
DateTime dt = DateTime.Now;
DALUsers.CIUser usr = new DALUsers.CIUser();
var existing = (from i in dc.CIUsers where i.UserName.CompareTo(username) == 0 && i.cid == cid select i);
if (existing.Count() > 0)
{
X.MessageBox.Info("Warning", "UserName already exists . Please try another!", UI.Warning).Show();
contin = false;
}
else
{
dc.CIUsers.InsertOnSubmit(usr);
dc.SubmitChanges();
}
if (contin)
{
DALUsers.CIUser usrNew = new DALUsers.CIUser();
var approved = (from k in dc.aspnet_Memberships //if user is not approved
where k.UserId == userid
select k).FirstOrDefault();
if (approved.IsApproved == false)
{
approved.IsApproved = true;
}
ProfileBase profile = ProfileBase.Create(username);
profile.SetPropertyValue("Mobile", mob);
profile.SetPropertyValue("Email", email);
profile.Save();
usrNew.UserId = usrId;
usrNew.cid = cid;
usrNew.FullName = fulname.LastName + " " + fulname.FirstName;
usrNew.Role = "User_x";
usrNew.SignRights = prime;
usrNew.IsPrime = prime;
usrNew.stid = stid;
usrNew.UserName = username;
usrNew.UserId = userid;
usrNew.CreatedDate = DateTime.Now;
usrNew.CreatedBy = HttpContext.Current.User.Identity.Name;
dc.CIUsers.InsertOnSubmit(usrNew);
dc.SubmitChanges();
result = 1;
X.MessageBox.Info("Success", "The user has been successfully added", UI.Success).Show();
}
}
else
X.MessageBox.Info("Error", "Could not find the user", UI.Danger).Show();
BLL.Security.SetProviderApp();
return result;
}
EDIT
I just saw that in my code there is this line:
DALUsers.aspnet_User user = new DALUsers.aspnet_User();
But the variable user is not used anywhere else in the code. Probably it has been left there... And its the only variable named user in my code. Is that causing the issue? But then why only on the production server?
EDIT
The weird part is that when I run my application from visual studio locally it works as a charm. But when I am adding a user in the application running on the production server when I am trying to add the second user it fails and I receive this error:
Value cannot be null. Parameter name: user
And if I try to login to my application after that it fails. I have to restart my website from iis to be able to login again.
Any ideas?

Well I cant find the error in your code but if you say that this error occurs only in server and that you are sure that your files are synched between server and your local machine, then probably the error lies in your web.config. Take a look

What info do I need to connect to Active Directory in C#?

I need to connect to a clients AD server to display information for all users. They've given me the following:
fqdn, netbios name and a domain controller. Is this enough to connect?
using (var context = new PrincipalContext(ContextType.Domain, "",))
using (var searcher = new PrincipalSearcher(new UserPrincipal(context)))
{
foreach (var result in searcher.FindAll())
{
DirectoryEntry de = result.GetUnderlyingObject() as DirectoryEntry;
}
}
Thanks!

I think Ryan was showing you the old way to do it. From your code it looks like you are using the newer classes.
// create a principal searcher for running a search operation
using (PrincipalSearcher pS = new PrincipalSearcher(uParams))
{
// assign the query filter property for the principal object you created
// you can also pass the user principal in the PrincipalSearcher constructor
pS.QueryFilter = uParams;
// run the query
using (PrincipalSearchResult<Principal> results = pS.FindAll())
{
foreach (Principal item in results)
{
UserPrincipal u = item as UserPrincipal;
list.Add(new MyCustomClass(u.UserPrincipalName)
{
Cn = u.Name,
Email = u.EmailAddress,
EmployeeId = u.EmployeeId,
NameFirst = u.GivenName,
NameLast = u.Surname,
ObjectSid = u.Sid.ToString(),
DistinguishedName = u.DistinguishedName,
SamAccount = u.SamAccountName
});
}
}
}
Note that the AD still imposes sometihng like a 1500 item limit on your queries so you will likely need to send your DirectoryEntry top to something like this:
/// <summary>
/// group member enumeration, simple and fast for large AD groups
/// </summary>
/// <param name="deGroup"></param>
/// <returns>list if distinguished names</returns>
public static List<string> GetMemberList(DirectoryEntry deGroup)
{
List<string> list = new List<string>();
DirectoryEntry entry = deGroup;
uint rangeStep = 1000;
uint rangeLow = 0;
uint rangeHigh = rangeLow + (rangeStep - 1);
bool lastQuery = false;
bool quitLoop = false;
do
{
string attributeWithRange;
if (!lastQuery)
{
attributeWithRange = String.Format("member;range={0}-{1}", rangeLow, rangeHigh);
}
else
{
attributeWithRange = String.Format("member;range={0}-*", rangeLow);
}
using (DirectorySearcher searcher = new DirectorySearcher(entry))
{
searcher.Filter = "(objectClass=*)";
//searcher.Filter = LdapObjectMgr.filterDisabledUsers;
searcher.PropertiesToLoad.Clear();
searcher.PropertiesToLoad.Add(attributeWithRange);
SearchResult results = searcher.FindOne();
foreach (string res in results.Properties.PropertyNames)
{
//list the property names
System.Diagnostics.Debug.WriteLine(res.ToString());
}
if (results.Properties.Contains(attributeWithRange))
{
foreach (object obj in results.Properties[attributeWithRange])
{
//Console.WriteLine(obj.GetType());
if (obj.GetType().Equals(typeof(System.String)))
{
}
else if (obj.GetType().Equals(typeof(System.Int32)))
{
}
//Console.WriteLine(obj.ToString());
list.Add(obj.ToString());
}
if (lastQuery)
{
quitLoop = true;
}
}
else
{
if (lastQuery == false)
{ lastQuery = true; }
else
{ quitLoop = true; }
}
if (!lastQuery)
{
rangeLow = rangeHigh + 1;
rangeHigh = rangeLow + (rangeStep - 1);
}
}
}
while (!quitLoop);
return list;
}

To connect via C# you will need something like this:
DirectoryEntry child = new DirectoryEntry("LDAP://" + domainControllerName + "/" +
objectDn, userName, password);
If you have the domain controller name, the object domain, a user name and a password, you should be good to go.
Just a heads up, you got downvoted because you didn't mention anything that you tried previously.

Retrieving user attributes from Active Directory using LDAP - JAVA

EDIT: I've posted the solution below.
I know you don't like these type of questions, but i've been struggling with this issue for half a day now.
I've written a C# code that fetches user attributes from our Active Directory using LDAP, the code works well.
The code is as follows:
DirectoryEntry dirEnt = new DirectoryEntry("LDAP://dc=dom,dc=int");
DirectorySearcher adSearch = new DirectorySearcher(dirEnt);
adSearch.SearchScope = SearchScope.Subtree;
adSearch.PageSize = 10000;
adSearch.Filter = "(&(objectClass=user))";
SearchResultCollection sColl = adSearch.FindAll();
foreach (SearchResult sResult in sColl)
{
string sConn = sResult.Properties["distinguishedName"][0].ToString();
DirectoryEntry dirEnt2 = new DirectoryEntry("LDAP://" + sConn);
...
// dirEnt2 contains ALL attributes for the user
}
I'm trying to port this code to Java, but it seems like that the technique I used in C# does not work too well in Java.
Using the following code
DirContext context;
ArrayList<String> nList = new ArrayList<String>();
Hashtable env = new Hashtable();
String username = ...;
String password = ...;
try {
env.put(Context.SECURITY_PRINCIPAL, username);
env.put(Context.SECURITY_CREDENTIALS, password);
env.put(Context.INITIAL_CONTEXT_FACTORY, "com.sun.jndi.ldap.LdapCtxFactory");
env.put(Context.PROVIDER_URL, ldapUri);
try {
context = new InitialDirContext(env);
} catch (NamingException e) {
throw new RuntimeException(e);
}
SearchControls ctrl = new SearchControls();
ctrl.setSearchScope(SearchControls.SUBTREE_SCOPE);
NamingEnumeration enumeration = context.search("", "(objectClass=user)",
ctrl);
while (enumeration.hasMore()) {
SearchResult result = (SearchResult) enumeration.next();
Attributes attribs = result.getAttributes();
NamingEnumeration values = ((BasicAttribute)
attribs.get("distinguishedName")).getAll();
while (values.hasMore()) {
nList.add(values.next().toString());
}
}
} catch (NamingException e) {
e.printStackTrace();
}
for (String sVar : nList ){
Hashtable env2 = new Hashtable();
env2.put(Context.SECURITY_PRINCIPAL, username);
env2.put(Context.SECURITY_CREDENTIALS, password);
env2.put(Context.INITIAL_CONTEXT_FACTORY,
"com.sun.jndi.ldap.LdapCtxFactory");
env2.put(Context.PROVIDER_URL, "ldap://DOM/" + sVar);
Attributes attrs = null;
try {
context = new InitialDirContext(env2);
attrs = context.getAttributes(sVar);
} catch (NamingException e) {
System.out.println(e.toString());
continue;
}
System.out.println(attrs.toString());
}
Yields that attrs only contains BASIC attributes regarding the user (such as samaccountname, displayname, etc)
and no 'email', 'telephone' or any other similar attributes.
Any help on the issue is blessed!

Here's the solution, sorry for the messy code/formatting
import java.util.Hashtable;
import javax.naming.Context;
import javax.naming.NamingEnumeration;
import javax.naming.NamingException;
import javax.naming.directory.*;
import javax.naming.ldap.*;
public class UserFetch {
public static void main(String[] args) {
try{
// Activate paged results
byte[] cookie = null;
int count=0;
int total;
Hashtable env = new Hashtable();
env.put(Context.INITIAL_CONTEXT_FACTORY,
"com.sun.jndi.ldap.LdapCtxFactory");
env.put(Context.REFERRAL, "follow");
env.put(Context.SECURITY_AUTHENTICATION, "Simple");
env.put(Context.SECURITY_PRINCIPAL, "USERNAME#DOM.COM");
env.put(Context.SECURITY_CREDENTIALS, "PASSWORD");
env.put(Context.PROVIDER_URL, "ldap://DOM.COM:389");
LdapContext ctx = new InitialLdapContext(env, null);
ctx.setRequestControls(new Control[]{
new PagedResultsControl(10000, Control.CRITICAL) });
do {
// Perform the search
NamingEnumeration results =
ctx.search("dc=DOM,dc=COM", "(&(objectclass=user)(employeeNumber=*))", getSimpleSearchControls());
// Iterate over a batch of search results
while (results != null && results.hasMore()) {
// Display an entry
SearchResult entry = (SearchResult)results.next();
Attributes attrs = entry.getAttributes ();
System.out.println(attrs.get("SAMAccountName")); // Username
System.out.println("Firstname: " +
attrs.get("givenname")); // firstname
System.out.println("Lastname: " + attrs.get("sn")); // lastname
System.out.println("EmployeeID " + attrs.get("employeeID"));
System.out.println("EmployeeNumber: " +
attrs.get("employeeNumber"));
// Handle the entry's response controls (if any)
}
// Examine the paged results control response
Control[] controls = ctx.getResponseControls();
if (controls != null) {
for (int i = 0; i < controls.length; i++) {
if (controls[i] instanceof PagedResultsResponseControl) {
PagedResultsResponseControl prrc =
(PagedResultsResponseControl)controls[i];
total = prrc.getResultSize();
cookie = prrc.getCookie();
} else {
// Handle other response controls (if any)
}
}
}
// Re-activate paged results
ctx.setRequestControls(new Control[]{
new PagedResultsControl(10000, cookie, Control.CRITICAL) });
} while (cookie != null);
} catch (Exception e) {
e.printStackTrace();
}
}
public static SearchControls getSimpleSearchControls() {
SearchControls searchControls = new SearchControls();
searchControls.setSearchScope(SearchControls.SUBTREE_SCOPE);
searchControls.setTimeLimit(30000);
String[] attrIDs =
{ "SAMAccountName", "sn", "givenname", "employeeID",
"employeeNumber" };
searchControls.setReturningAttributes(attrIDs);
return searchControls;
}
}

Try setting the returned attributes on your SearchControls
ctrl.setReturningAttributes(new String[] {"email", "telephone"});

C# Active Directory: Get domain name of user?

I know that this type of question has been asked before, but other methods are failing me right now.
As it stands our windows service polls AD, given an LDAP (i.e. LDAP://10.32.16.80) and a list of usergroups within that AD server to search for.
It retrieves all users within those given groups, recursively searching those groups for more groups as well.
Each user is then added to another applications authenticated users list.
This part of the application is running successfully. However, we're in need of each user's friendly domain name (i.e. the part of their login DOMAIN/username)
So if there is a user that is part of TEST domain, named Steve: TEST/steve is his login.
I'm able to find steve in the AD, however I also need "TEST" to be stored along with his AD information.
Again, I can find 'steve' fine by using a directory searcher and the LDAP IP I'm given, but given the LDAP IP, how can I find the friendly domain name?
When I try the following code I'm given an error when attempting to access the 'defaultNamingContext':
System.Runtime.InteropServices.COMException (0x8007202A): The authentication mechanism is unknown.
Here is the code:
private string SetCurrentDomain(string server)
{
string result = string.Empty;
try
{
logger.Debug("'SetCurrentDomain'; Instantiating rootDSE LDAP");
DirectoryEntry ldapRoot = new DirectoryEntry(server + "/rootDSE", username, password);
logger.Debug("'SetCurrentDomain'; Successfully instantiated rootDSE LDAP");
logger.Debug("Attempting to retrieve 'defaultNamingContext'...");
string domain = (string)ldapRoot.Properties["defaultNamingContext"][0]; //THIS IS WHERE I HIT THE COMEXCEPTION
logger.Debug("Retrieved 'defaultNamingContext': " + domain);
if (!domain.IsEmpty())
{
logger.Debug("'SetCurrentDomain'; Instantiating partitions/configuration LDAP entry");
DirectoryEntry parts = new DirectoryEntry(server + "/CN=Partitions,CN=Configuration," + domain, username, password);
logger.Debug("'SetCurrentDomain'; Successfully instantiated partitions/configuration LDAP entry");
foreach (DirectoryEntry part in parts.Children)
{
if (part.Properties["nCName"] != null && (string)part.Properties["nCName"][0] != null)
{
logger.Debug("'SetCurrentDomain'; Found property nCName");
if ((string)part.Properties["nCName"][0] == domain)
{
logger.Debug("'SetCurrentDomain'; nCName matched defaultnamingcontext");
result = (string)part.Properties["NetBIOSName"][0];
logger.Debug("'SetCurrentDomain'; Found NetBIOSName (friendly domain name): " + result);
break;
}
}
}
}
logger.Debug("finished setting current domain...");
}
catch (Exception ex)
{
logger.Error("error attempting to set domain:" + ex.ToString());
}
return result;
}
edit
I added this sample method in order to attempt a suggestion but am getting an exception: "Unspecified error" when I hit the "FindAll()" call on the searcher.
The string being passed in is: "CN=TEST USER,CN=Users,DC=tempe,DC=ktregression,DC=com"
private string GetUserDomain(string dn)
{
string domain = string.Empty;
string firstPart = dn.Substring(dn.IndexOf("DC="));
string secondPart = "CN=Partitions,CN=Configuration," + firstPart;
DirectoryEntry root = new DirectoryEntry(secondPart, textBox2.Text, textBox3.Text);
DirectorySearcher searcher = new DirectorySearcher(root);
searcher.SearchScope = SearchScope.Subtree;
searcher.ReferralChasing = ReferralChasingOption.All;
searcher.Filter = "(&(nCName=" + firstPart + ")(nETBIOSName=*))";
try
{
SearchResultCollection rs = searcher.FindAll();
if (rs != null)
{
domain = GetProperty(rs[0], "nETBIOSName");
}
}
catch (Exception ex)
{
}
return domain;

This article helped me much to understand how to work with the Active Directory.
Howto: (Almost) Everything In Active Directory via C#
From this point forward, if you require further assitance, please let me know with proper questions in comment, and I shall answer them for you to the best of my knowledge.
EDIT #1
You had better go with this example's filter instead. I have written some sample code to briefly show how to work with the System.DirectoryServices and System.DirectoryServices.ActiveDirectory namespaces. The System.DirectoryServices.ActiveDirectory namespace is used to retrieve information about the domains within your Forest.
private IEnumerable<DirectoryEntry> GetDomains() {
ICollection<string> domains = new List<string>();
// Querying the current Forest for the domains within.
foreach(Domain d in Forest.GetCurrentForest().Domains)
domains.Add(d.Name);
return domains;
}
private string GetDomainFullName(string friendlyName) {
DirectoryContext context = new DirectoryContext(DirectoryContextType.Domain, friendlyName);
Domain domain = Domain.GetDomain(context);
return domain.Name;
}
private IEnumerable<string> GetUserDomain(string userName) {
foreach(string d in GetDomains())
// From the domains obtained from the Forest, we search the domain subtree for the given userName.
using (DirectoryEntry domain = new DirectoryEntry(GetDomainFullName(d))) {
using (DirectorySearcher searcher = new DirectorySearcher()){
searcher.SearchRoot = domain;
searcher.SearchScope = SearchScope.Subtree;
searcher.PropertiesToLoad.Add("sAMAccountName");
// The Filter is very important, so is its query string. The 'objectClass' parameter is mandatory.
// Once we specified the 'objectClass', we want to look for the user whose login
// login is userName.
searcher.Filter = string.Format("(&(objectClass=user)(sAMAccountName={0}))", userName);
try {
SearchResultCollection results = searcher.FindAll();
// If the user cannot be found, then let's check next domain.
if (results == null || results.Count = 0)
continue;
// Here, we yield return for we want all of the domain which this userName is authenticated.
yield return domain.Path;
} finally {
searcher.Dispose();
domain.Dispose();
}
}
}
Here, I didn't test this code and might have some minor issue to fix. This sample is provided as-is for the sake of helping you. I hope this will help.
EDIT #2
I found out another way out:
You have first to look whether you can find the user account within your domain;
If found, then get the domain NetBIOS Name; and
concatenate it to a backslash (****) and the found login.
The example below uses a NUnit TestCase which you can test for yourself and see if it does what you are required to.
[TestCase("LDAP://fully.qualified.domain.name", "TestUser1")]
public void GetNetBiosName(string ldapUrl, string login)
string netBiosName = null;
string foundLogin = null;
using (DirectoryEntry root = new DirectoryEntry(ldapUrl))
Using (DirectorySearcher searcher = new DirectorySearcher(root) {
searcher.SearchScope = SearchScope.Subtree;
searcher.PropertiesToLoad.Add("sAMAccountName");
searcher.Filter = string.Format("(&(objectClass=user)(sAMAccountName={0}))", login);
SearchResult result = null;
try {
result = searcher.FindOne();
if (result == null)
if (string.Equals(login, result.GetDirectoryEntry().Properties("sAMAccountName").Value))
foundLogin = result.GetDirectoryEntry().Properties("sAMAccountName").Value
} finally {
searcher.Dispose();
root.Dispose();
if (result != null) result = null;
}
}
if (!string.IsNullOrEmpty(foundLogin))
using (DirectoryEntry root = new DirectoryEntry(ldapUrl.Insert(7, "CN=Partitions,CN=Configuration,DC=").Replace(".", ",DC="))
Using DirectorySearcher searcher = new DirectorySearcher(root)
searcher.Filter = "nETBIOSName=*";
searcher.PropertiesToLoad.Add("cn");
SearchResultCollection results = null;
try {
results = searcher.FindAll();
if (results != null && results.Count > 0 && results[0] != null) {
ResultPropertyValueCollection values = results[0].Properties("cn");
netBiosName = rpvc[0].ToString();
} finally {
searcher.Dispose();
root.Dispose();
if (results != null) {
results.Dispose();
results = null;
}
}
}
Assert.AreEqual("FULLY\TESTUSER1", string.Concat(netBiosName, "\", foundLogin).ToUpperInvariant())
}
The source from which I inspired myself is:
Find the NetBios Name of a domain in AD

Since I could not find any example code I would like to share my own solution. This will search the parents of the DirectoryEntry object until it hits the domainDNS class.
using System.DirectoryServices;
public static class Methods
{
public static T ldap_get_value<T>(PropertyValueCollection property)
{
object value = null;
foreach (object tmpValue in property) value = tmpValue;
return (T)value;
}
public static string ldap_get_domainname(DirectoryEntry entry)
{
if (entry == null || entry.Parent == null) return null;
using (DirectoryEntry parent = entry.Parent)
{
if (ldap_get_value<string>(parent.Properties["objectClass"]) == "domainDNS")
return ldap_get_value<string>(parent.Properties["dc"]);
else
return ldap_get_domainname(parent);
}
}
}
Use it like this:
string[] _properties = new string[] { "objectClass", "distinguishedName", "samAccountName", "userPrincipalName", "displayName", "mail", "title", "company", "thumbnailPhoto", "useraccountcontrol" };
string account = "my-user-name";
// OR even better:
// string account = "my-user-name#DOMAIN.local";
using (DirectoryEntry ldap = new DirectoryEntry())
{
using (DirectorySearcher searcher = new DirectorySearcher(ldap))
{
searcher.PropertiesToLoad.AddRange(_properties);
if (account.Contains('#')) searcher.Filter = "(userPrincipalName=" + account + ")";
else searcher.Filter = "(samAccountName=" + account + ")";
var user = searcher.FindOne().GetDirectoryEntry();
Console.WriteLine("Name: " + Methods.ldap_get_value<string>(user.Properties["displayName"]));
Console.WriteLine("Domain: " + Methods.ldap_get_domainname(user));
Console.WriteLine("Login: " + Methods.ldap_get_domainname(user) + "\\" + Methods.ldap_get_value<string>(user.Properties["samAccountName"]));
}
}
I haven't got a forest to test it on but in theory this should cut it.

You can retrieve the name of the domain that the current user is on using the Environment.UserDomainName Property.
string domainName;
domainName = System.Environment.UserDomainName;

Maybe not entirely correct but...
DirectoryEntry dirEntry = new DirectoryEntry();
DirectorySearcher dirSearcher = new DirectorySearcher(dirEntry);
dirSearcher.SearchScope = SearchScope.Subtree;
dirSearcher.Filter = string.Format("(&(objectClass=user)(|(cn={0})(sn={0}*)(givenName={0})(sAMAccountName={0}*)))", userName);
var searchResults = dirSearcher.FindAll();
foreach (SearchResult sr in searchResults)
{
var de = sr.GetDirectoryEntry();
string user = de.Properties["SAMAccountName"][0].ToString();
string domain = de.Path.ToString().Split(new [] { ",DC=" },StringSplitOptions.None)[1];
MessageBox.Show(domain + "/" + user);
}
Because the value of de.Path is
LDAP://CN=FullName,DC=domain,DC=local