Thanks for the explanation Joe. I am currently on chapter three of your book. 
Can't read it fast enough.
 
Do you know if 'deUser.commitchanges' is smart enough not to send an update 
request to AD if the collection is not dirty?
 
Thanks
 
Y

________________________________

From: [EMAIL PROTECTED] on behalf of Joe Kaplan
Sent: Thu 28/12/2006 4:10 PM
To: ActiveDir@mail.activedir.org
Subject: Re: [ActiveDir] DirectoryServices vb.net is broken.



I'm not sure if it is a bug or not.  Generally,  I always use .Value to set
a value and only use Add if I'm explicitly trying to add an additional value
to a multi-valued attribute that already has values.  Same basic approach
for Remove.  That helps keep me out of trouble.  :)

It is interesting, because there have been MANY problems with the various
techniques used to modify the property cache in S.DS over the years.  I
think the current design is the least problematic.  The issue really stems
from the way S.DS tries to represent the property cache as a stateful
collection of collections on the DirectoryEntry, but ADSI does this in a
"non-stateful" way using Put and PutEx to modify.  The other issue has to do
with the fact that each ADSI provider does stuff slighly differently under
the hood when it talks to the actual API doing the work (LDAP for LDAP, Net*
for WinNT, ABO for IIS provider, etc.).

The alternative is to just switch over to using
System.DirectoryServices.Protocols.  That basically talks directly to LDAP
via wldap32.dll (like the www.joeware.net tools do, but going through .NET
first).  However, you tend to have to write more code to do the same thing
and learn a lot more about LDAP that you might want to, so it is a two-edged
sword.  The most difficult things are learning how to use the advanced LDAP
controls to do things like paged searches and security descriptor
read/modify operations.  ADSI tries to make that stuff easy for you.

Note also that there is nothing really new and exciting in DS programming in
.NET 3.0.  The next wave of stuff for DS will be in the next .NET rev that
ships with the next Visual Studio.  .NET 3.0 is actually the .NET 2.0
runtime with additional assemblies that support WCF, WPF, WWF and CardSpace.
Many of the assemblies are unchanged and actually run straight from the .NET
2.0 install directory.  The good news is that our book is not out of date
for at least another year.  :)

The next version is supposed to have strongly typed support for users and
groups, kind of like S.DS.ActiveDirectory adds strongly typed support for
concepts like Forests, Domains, Trusts, Schema, Replication etc.

There are a few minor tweaks to ADSI in Windows Vista (remember that ADSI
comes with Windows, so it is on a different release cycle than S.DS, which
comes with .NET and usually cycles with Visual Studio but sometimes cycles
with Windows).  However, these are pretty low key.

Joe K.

----- Original Message -----
From: "AD" <[EMAIL PROTECTED]>
To: <ActiveDir@mail.activedir.org>
Sent: Thursday, December 28, 2006 1:40 PM
Subject: RE: [ActiveDir] DirectoryServices vb.net is broken.


One last comment Joe,

Do you think that is a bug with DSS? That now means depending of the
attribute, you have to use different method? Kinda makes it complicated
don't you think?.

Now I have to "hard code" attribute names in my program.

if attribute="description" do this
else
do it this way.

That sucks Microsoft.

Y

________________________________

From: [EMAIL PROTECTED] on behalf of Joe Kaplan
Sent: Thu 28/12/2006 1:46 PM
To: ActiveDir@mail.activedir.org
Subject: Re: [ActiveDir] DirectoryServices vb.net is broken.



I'm saying that those two are not equivalent functions under the hood.  Add
typically does a PutEx with the append flag, while Put just does a "put",
which is essentially an LDAP "update" operation.  I think you would have the
same problem if you invoked PutEx and used the Append flag.

.Value uses PutEx, but with the ADSI replace flag, which boils down to an
LDAP update operation.

Aren't all of the layers fun?  :)

You can dig into the details a little more by using Reflector to reverse
compile System.DirectoryServices into your language of choice.  That is how
Ryan and I learned most of what we know.  Figuring out how ADSI calls LDAP
is pretty hard unless you have access to the Microsoft source code.

Sorry if the example in 3.13 was at all misleading or inconsistent, but I'll
stand by the more detailed stuff on attribute modification in Ch 6.  Thanks
for buying it and I hope it helps more than hurts.  There is an inevitable
amount of hair loss that must occur with any new LDAP programming project,
but hopefully it won't require prescription drugs or surgery to replace.

Joe K.

----- Original Message -----
From: "AD" <[EMAIL PROTECTED]>
To: <ActiveDir@mail.activedir.org>
Sent: Thursday, December 28, 2006 12:06 PM
Subject: RE: [ActiveDir] DirectoryServices vb.net is broken.


It worked. Thanks a million. Hopefully my hair won't take to long to grow
back.

I bought your book last week from amazon. I currently reading chapter 3.
Actually took your example code. See 3.13.vb. Isn't that funny?

I thought DirectoryServices was a wrapper to ADSI? Why do you say they are
not equivalent?

Y



They aren't equivalent.  Try using the .Value property instead:

user.Properties("description").Value = xxxx

Description is a funny property in AD in that the schema says that it allows
multiple values, but the DS itself will only allow it to contain a single
value for backward compatibility with previous DS APIs.  That might be part
of the problem here.

In any event, it is generally always good practice to use the .Value
property to set a single value.  There is  more info on this in ch 6 of our
book (www.directoryprogramming.net).

Joe K.

----- Original Message -----
From: "AD" <[EMAIL PROTECTED]>
To: <ActiveDir@mail.activedir.org>
Sent: Thursday, December 28, 2006 10:13 AM
Subject: [ActiveDir] DirectoryServices vb.net is broken.


I have a user with no description attribute.

Anyone know why this works?

User.Invoke("put", New Object() {"description", txtBxNewDescription.Text})
User.commitChanges

but this doesn't

User.Properties("Description").Add(txtBxNewDescription.Text)
User.commitChanges

I get the following error message.

ComError {"A constraint violation occurred. (Exception from HRESULT:
0x8007202F)"} System.DirectoryServices.DirectoryServicesCOMException

Thanks

Yves St-Cyr
List info   : http://www.activedir.org/List.aspx
List FAQ    : http://www.activedir.org/ListFAQ.aspx
List archive: http://www.activedir.org/ma/default.aspx

List info   : http://www.activedir.org/List.aspx
List FAQ    : http://www.activedir.org/ListFAQ.aspx
List archive: http://www.activedir.org/ma/default.aspx



List info   : http://www.activedir.org/List.aspx
List FAQ    : http://www.activedir.org/ListFAQ.aspx
List archive: http://www.activedir.org/ma/default.aspx



List info   : http://www.activedir.org/List.aspx
List FAQ    : http://www.activedir.org/ListFAQ.aspx
List archive: http://www.activedir.org/ma/default.aspx


<<winmail.dat>>

Reply via email to