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Authenticating Active Directory user in ASP.NET

, 2 May 2002
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How to authenticate the AD user in ASP.NET by using Directory Services


In this article I am concentrating on the validation of the Active Directory user through the ASP.NET pages and in fact you can validate the user in any sort of code (non-ASP.NET). The basic things remain the same but the implementation part will depend on the type of requirement. First of all you need to inclue the following code in the .cs file to freely use the directory services.

using System.DirectoryServices;

This will allow you to get the namespace available in your code. Then to get in to the Active Directory server you need to provide the LDAP path which will find the server from the network. Now this you can will be encapsulated in the DirectoryEntry class. The following code will try to contect the server by the user name and passwords provided by you.

DirectoryEntry entry = new DirectoryEntry(LDAP://ADservername,<BR>    "username","password");

As per the user name and password this will give you the abstracted property names and value pair collection. Which you can filter later to find out the information specific to the user. To get the specific information you need the DirectorySercher object which will find all the information you need in name value pairs.

DirectorySearcher mySearcher = new     DirectorySearcher(entry);
    SearchResultCollection results;
    mySearcher.Filter ("name=value");
      results = mySearcher.FindAll();
mySearcher.Filter  ("cn=jignesh");

Over here I try to get the information for the user named jignesh. So for the filter string it is cn=jignesh. This is specific to Active Directory; and you should know all LDAP information about your Active Direcotry. Now is the time to rotate through the name value pair which is quite easy and which you can easily understand.

    foreach(SearchResult resEnt in results)
                    ResultPropertyCollection propcoll=resEnt.Properties;
                    foreach(string key in propcoll.PropertyNames)
                        foreach(object values in propcoll[key])
                            //name and value collection retrival


Thats it. This way you can connect with the server through the LDAP and fetch all the information from that. Like user name password etc. You can set the parameters too.


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Comments and Discussions

GeneralFinding domino groups of logged in user by using Pinmembersuperkelvin8823-Jul-09 17:32 
Questioncount and display users who are logedin Pinmembermnalammwb25-Mar-08 2:19 
Questionhow to check username & password from AD Pinmemberasifbhura16-Jun-07 21:43 
AnswerRe: how to check username & password from AD PinmemberGovardhana Reddy2-Jul-07 21:22 
QuestionLDAPS version? Pinmembersallas00019-Oct-06 21:07 
QuestionHow to list members of a group? PinmemberPete Burgess24-Apr-06 0:06 
AnswerRe: How to list members of a group? PinmemberChetan Ranpariya18-Jul-06 0:56 
GeneralRe: How to list members of a group? PinmemberJacks Pro14-May-08 21:37 
GeneralRe: How to list members of a group? Pinmemberrandy_orton6469-Mar-08 2:31 
QuestionHow do I get the user password PinmemberJP01122-Nov-05 10:52 
GeneralASP vs Windows PinsussAnonymous7-Dec-04 9:22 
GeneralRe: ASP vs Windows PinmemberRyan Fenner12-Sep-05 13:51 
Generalactive directory PinmemberDgigoloB22-Nov-04 23:55 
Generalproblem with ldap path &quot;LDAP://DC=onecity,DC=corp,DC=fabrikam,DC=com&quot; Pinmembergautam7924-Jun-04 12:00 
GeneralRe: problem with ldap path &quot;LDAP://DC=onecity,DC=corp,DC=fabrikam,DC=com&quot; Pinmembermpemberton24-Jun-04 13:22 
GeneralRe: problem with ldap path &quot;LDAP://DC=onecity,DC=corp,DC=fabrikam,DC=com&quot; Pinmemberlemravec29-Nov-04 10:09 
GeneralLDAP connection problems Pinmemberragibhusain11-Feb-04 7:24 
GeneralRe: LDAP connection problems Pinmemberairstep28-Sep-04 8:17 
Here is some code I put together to connect to an Imail LDAP server with VB.NET. Note: the Imail LDAP service must be running.
Dim entry As DirectoryEntry
entry = New DirectoryEntry("LDAP://localhost/", "cn=username,", "password", AuthenticationTypes.ReadonlyServer)
Dim srch As DirectorySearcher
srch = New DirectorySearcher(entry)
srch.Filter = "(o=*)"
Dim results As SearchResultCollection
results = srch.FindAll()
Dim result As SearchResult
Dim propColl As ResultPropertyCollection
Dim strKey As String
Dim obProp As Object
For Each result In results
propColl = result.Properties
For Each strKey In propColl.PropertyNames
For Each obProp In propColl(strKey)

GeneralRe: LDAP connection problems Pinmemberfdfdfdfdfdfd15-Apr-07 2:13 
GeneralFinding groups of logged in user Pinsussrdever49-Apr-03 14:48 
GeneralRe: Finding groups of logged in user PinmemberGeorge Vigelette3-Jun-03 4:56 
GeneralRe: Finding groups of logged in user PinsussAnonymous19-Jul-03 23:35 
GeneralRe: Finding groups of logged in user PinmemberMike-EEEE16-Apr-04 7:08 
GeneralRe: Finding groups of logged in user Pinmembersuperkelvin8823-Jul-09 17:45 
GeneralRe: Finding groups of logged in user Pinmembereopie21-Jul-05 14:15 

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