Getting the NT-ID of a user in SharePoint

Question

What is the simplest way to get the NT-ID of a user in a C# application? I would probably need to get it only having a name of the user, or maybe an email address.

Answer 1

From within SharePoint, you can get a user's Active Directory information (including display name and email) using SPUtility.ResolveWindowsPrincipal:

http://msdn.microsoft.com/en-us/library/microsoft.sharepoint.utilities.sputility.resolvewindowsprincipal.aspx

For example:

SPPrincipalInfo pi = SPUtility.ResolveWindowsPrincipal(SPContext.Current.Site.WebApplication, "MYDOMAIN\\myusername", SPPrincipalType.All, false);

Outside of SharePoint, you want to look at the System.DirectoryServices namespace.

Answer 2

Most of the time, you can get it from the current web, for example:

string login = SPContext.Current.Web.CurrentUser.LoginName
string mail = SPContext.Current.Web.CurrentUser.Email