Windows Authentication User.Identity.Name to email address

Question

I have already tried to use How to obtain email address with window authentication, but a question remains:

I know how to ask for email address for John Smith, but what I get as authentication name is like INTRA\\JohnSmith3 or DEP21\\JohnSmith

How can I map INTRA\\JohnSmith3 or DEP21\\JohnSmith to the correct John Smith in AD?

Answer 1

What you get from Windows Authentication is the SAM Account Name. You need to look this up in Active Directory.

You can query Active Directory for users like this:

(&(objectCategory=person)(objectClass=user)(sAMAccountName=JohnSmith3))

In code:

string filter = "(&(objectCategory=person)"
     + "(objectClass=user)"
     + "(sAMAccountName=" + samAccountName + "))";
DirectorySearcher search = new DirectorySearcher(myLdapConnection);
search.Filter = filter;
SearchResult result = search.FindOne();
DirectoryEntry de = result.GetDirectoryEntry();