RE: Check If User Exists...

From: Grigs (Grigs_at_discussions.microsoft.com)
Date: 07/09/04 

Date: Fri, 9 Jul 2004 06:48:02 -0700

Well with further searching and testing I have figured out my own problem to what I figured was a simple problem. Here is the full code you would need to verify if a given "login name" is tied to any user in your network with VB.Net.

The loginame name passed in as a string. If it is a valid user's login name, then True will be returned, otherwise False. Be sure the change the NetworkName to your Network name. The sLoginName is not case sensitive.

You must add a Reference to the system.DirectoryServices .dll for this to work.

Private Function IsValidLoginName(ByVal sLoginName As String) As Boolean

  ' Search for a user with a given login name

  Dim oDirEntry As New System.DirectoryServices.DirectoryEntry("LDAP://NetworkName")
  Dim oDirSearch As New System.DirectoryServices.DirectorySearcher(oDirEntry)
  Dim oResult As System.DirectoryServices.SearchResult

  oDirSearch.Filter = _
    "(&(objectClass=user)(samaccountname=" & sLoginName & "))"

  Try
    oResult = oDirSearch.FindOne
    IsValidLoginName = True
  Catch e As Exception
    IsValidLoginName = False
  End Try

End Function 

-- 
Thanx,
Grigs
"Grigs" wrote:
> Hello,
> 
> Long time coder, but Very very new to .Net and am wanting to add some code to an existing VB.Net app.
> 
> I will be given a users login name and want to verify that it is still a valid login name.  I assume I can do it through the System.DirectoryServices.DirectorySearcher object but tried a few things and didn't get it to work.  (again, very new to .Net at least).
> 
> I simply want to do some sort of search on the passed in "login name" and if that user is found then I continue.  I have to believe this is only a couple lines of code.  If the above class I mentioned is too bulky or someone has a better way, please send it.
> 
> -- 
> Thanx,
> Grigs

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