active directory users on asp.net

Question

I want to create a directory intranet web site using Active Directory for our company. I got this so far, but when I run in debug mode the code breaks in searchResultCollection....search.findAll(); displaying:

[DirectoryServicesCOMException (0x80072020): An operations error occurred.]

I have tried changing the IIS asp.net impersonation to enabled but I get a HTTP Error 500.24. My user name has read access to Active Directory. Is there some thing I am missing or could some one point me to the right direction. I have looked everywhere this is were I'm getting stuck.

Thanks in advance for any help.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;
using System.DirectoryServices;
using System.Web.Security;

public partial class _Default : System.Web.UI.Page
{
     protected void Page_Load(object sender, EventArgs e)
     {
          if (!Page.IsPostBack)
             GetADUsers();
      }

      public void GetADUsers()
      {
          DirectoryEntry myLdap = new DirectoryEntry("LDAP://OU=Nix,DC=systems,DC=com");
          DirectorySearcher search = new DirectorySearcher(myLdap);
          search.CacheResults = true;
          search.SearchScope = SearchScope.Subtree;
          search.Filter = "(objectlass=person)";
          SearchResultCollection allResults = search.FindAll();

          foreach (SearchResult sr in allResults)
          {
               Response.Write(sr.Properties["name"].ToString());
          }
     }

Answer 1

You can use a PrincipalSearcher and a "query-by-example" principal to do your searching:

// create your domain context
using (PrincipalContext ctx = new PrincipalContext(ContextType.Domain))
{
   // define a "query-by-example" principal - here, we search for a UserPrincipal 
   // and with the first name (GivenName) of "Bruce" and a last name (Surname) of "Miller"
   UserPrincipal qbeUser = new UserPrincipal(ctx);
   qbeUser.GivenName = "Bruce";
   qbeUser.Surname = "Miller";

   // create your principal searcher passing in the QBE principal    
   PrincipalSearcher srch = new PrincipalSearcher(qbeUser);

   // find all matches
   foreach(var found in srch.FindAll())
   {
       // do whatever here - "found" is of type "Principal" - it could be user, group, computer.....          
   }
}

If you haven't already - absolutely read the MSDN article Managing Directory Security Principals in the .NET Framework 3.5 which shows nicely how to make the best use of the new features in System.DirectoryServices.AccountManagement . Or see the MSDN documentation on the System.DirectoryServices.AccountManagement namespace.

Of course, depending on your need, you might want to specify other properties on that "query-by-example" user principal you create:

• DisplayName (typically: first name + space + last name)
• SAM Account Name - your Windows/AD account name
• User Principal Name - your "username@yourcompany.com" style name

You can specify any of the properties on the UserPrincipal and use those as "query-by-example" for your PrincipalSearcher .

Answer 2

After self reboot, I tested again it ran without errors then added the rest code to display in a gridview.

 public partial class _Default : System.Web.UI.Page
 {
 protected void Page_Load(object sender, EventArgs e)
 {
      if (!Page.IsPostBack)
         GetADUsers();
  }

  public void GetADUsers()
  {
      DirectoryEntry myLdap = new DirectoryEntry("LDAP://OU=Nix,DC=systems,DC=com");
      DirectorySearcher search = new DirectorySearcher(myLdap);
      search.CacheResults = true;
      search.SearchScope = SearchScope.Subtree;
      search.Filter = "(objectlass=person)";
      SearchResultCollection allResults = search.FindAll();
      search.PropertiesToLoad.Add("samaccountname");

      Grid1.DataSource = allResults;
      Grid1.DataBind();
 }