using linq on active directories underlying object

Question

Currently my code is:

using (var context = new PrincipalContext(ContextType.Domain, adDomain))
{
    using (var searcher = new PrincipalSearcher(new UserPrincipal(context)))
    {
        foreach (Principal result in searcher.FindAll())
        {
            DirectoryEntry entry = result.GetUnderlyingObject() as DirectoryEntry;
            if (entry.Properties["Company"].Value?.ToString() == "My Company")
            {
                // do some stuff
            }
        }
    }
}

I was just wondering if it would be possible to do a LINQ statement instead of the if statement to only get entries I am interested in.

Something like this:

foreach (var entry in searcher.FindAll()
    .Where(x => x.GetUnderlyingObject<DirectoryEntries>()
    .Properties["Company"].Value?.ToString() == "MY Company"))
{
    // do some stuff
}

It actually returns object. And Bryan you don't have generic `GetUnderlayingObject` method add `Cast()` after `Where`... — Johnny, Mar 12 '19 at 18:13
Please take a look again. I follow your link. Return type is object. — Johnny, Mar 12 '19 at 18:16
@Johnny My mistake. The wording in the description that I pasted is what made me think that. You are correct. I've deleted my comments to eliminate confusion. — Lews Therin, Mar 12 '19 at 18:17

haldo · Accepted Answer · 2019-03-14T16:33:57.507

3

It should be possible. You can use Select() first to cast the object to the DirectoryEntry's. Something like this should work:

var entry = searcher.FindAll()
    .Select(x => (DirectoryEntry)x.GetUnderlyingObject())
    .Where(x => x.Properties["Company"].Value?.ToString() == "My Company")
    .FirstOrDefault();  // or .ToList() depending on your requirements

if (entry != null)
{
    // do some stuff
}

edited Mar 14 '19 at 16:33

answered Mar 12 '19 at 18:11

haldo

14,512
5
46
52

Good call on the `Select` to do the casting and the `GetDirectoryEntry()` call. I fixed my answer after reading this. Upvoted. – Lews Therin Mar 12 '19 at 18:19

Lews Therin · Answer 2 · 2019-03-12T18:19:06.543

You shouldn't need the foreach. Try this:

var myCompany = searcher.FindAll()
    .Select(x => (DirectoryEntry)x.GetUnderlyingObject())
    .Where(x => x.Properties["Company"].Value?.ToString() == "MY Company")
    .ToList();

if (myCompany != null)
    // Do something with myCompany

Off-topic: You can stack using statements to eliminate some nesting:

using (var context = new PrincipalContext(ContextType.Domain, adDomain))
using (var searcher = new PrincipalSearcher(new UserPrincipal(context)))
{
    // Do stuff
}

score 0 · Answer 3 · answered Mar 12 '19 at 18:05

0

Yeah Bryan, that looks like a solution. I don´t have the types of everything to test it, but that with a ToList() at the end to allow the foreach to iterate should work.

I would put it above the foreach in a var to see the list it produces before iterating.

answered Mar 12 '19 at 18:05

Matt

319
2
7

well at the moment it gives a compile error stating PrincipalGetInderLyingObject() cannot be used with type arguments. hold on I'll make a fiddle. – Bryan Dellinger Mar 12 '19 at 18:08

using linq on active directories underlying object

3 Answers3