How can I retrieve the phone number from Active Directory using User Principal Context-CodePudding

This code works perfectly to get the phone number from Active Directory using the username and password

    public string GetPhone(string domain, string username, string pwd)
    {
        _path = "LDAP://"   domain;
        string domainAndUsername = domain   @"\"   username;
        DirectoryEntry entry = new DirectoryEntry(_path, domainAndUsername, pwd);
        string telephoneNumber = string.Empty;

        try
        {
            object obj = entry.NativeObject;
            DirectorySearcher search = new DirectorySearcher(entry);

            SearchResult result = search.FindOne();

            var myEntry = result.GetDirectoryEntry();
            telephoneNumber = myEntry.Properties["telephoneNumber"].Value.ToString();
        }
        catch (Exception ex)
        {

            throw new Exception("Error obtaining phone number. "   ex.Message);
        }
        return telephoneNumber;
    }

However, I have access to the user password only on the login page. I do have the User context being generated though that is accessible from anywhere within the application (Context.User which is of System.Security.Principal.IPrincipal type)

Thus, how can I get the phone from Active Directory using an already available Context.User object?

Thank you very much in advance

CodePudding user response：

The User object you get will have the SID of the user. With that, you can use the SID binding LDAP path in DirectoryEntry: LDAP://<SID=XXXXX>

var user = new DirectoryEntry(
    $"LDAP://<SID={((WindowsIdentity) HttpContext.User.Identity).User.Value}>");

user.RefreshCache(new [] { "telephoneNumber" });
var telephoneNumber = user.Properties["telephoneNumber"]?.Value as string;

The use of RefreshCache is to load only the telephoneNumber attribute. Otherwise, when you first use .Properties, it will retrieve every attribute, which is a waste of time and bandwidth.

CodePudding user response：

Looks like I overcomplicated everything and solution is quite simple

    private void SetPhone()
    {
        DirectoryEntry entryDomain = new DirectoryEntry("LDAP://"   domain);
        DirectorySearcher ds = new DirectorySearcher(entryDomain);

        string lastName = Context.User.Identity.Name.Split(' ')[Context.User.Identity.Name.Split(' ').Length - 1];

        ds.Filter = "(sn="   lastName   ")";
        SearchResult sr = ds.FindOne();

        string telephoneNumber = sr.Properties["telephoneNumber"][0].ToString();
        telephoneNumber = telephoneNumber.Insert(0, "(").Insert(4, ")").Insert(5, " ").Insert(9, "-");
        Session["UserPhone"] = String.Format("{0:(###) ###-####}", telephoneNumber); ;
    }