Get UPN or email for logged in user in a .NET web application

Question

I\'m not a .NET developer, and I have a feeling this would be trivial for someone who is:

I have a C# web application that makes user of the user credentials of the

Answer 1

Try:

System.Security.Principal.WindowsIdentity.GetCurrent().Name

Answer 2

Meanwhile (.NET 3.5) this is a one-liner:

System.DirectoryServices.AccountManagement.UserPrincipal.Current.EmailAddress

for the email, or

System.DirectoryServices.AccountManagement.UserPrincipal.Current.UserPrincipalName

for the UPN.

Answer 3

To query active directory using a directory searcher you need to do something like this (totally untested code):

    string userName = System.Security.Principal.WindowsIdentity.GetCurrent().Name;
    string ldapPath = "LDAP://domain.company.com";

    public string GetEmail(string userName, string ldapPath)
    {
        using (DirectoryEntry root = new DirectoryEntry(ldapPath))
        {
            DirectorySearcher searcher = new DirectorySearcher(root);
            searcher.Filter = string.Format(@"(&(sAMAccountName={0}))", userName);
            searcher.PropertiesToLoad = "mail";

            SearchResult result = searcher.FindOne();

            if (result != null)
            {
                PropertyValueCollection property = result.Properties["mail"];
                return (string)property.Value;
            }
            else
            { 
                // something bad happened
            }
        }
    }