How to check if a given user is a member of the built-in Administrators group?

Question

I need to check programmatically (in .NET) whether a given user (domain account) is a member of the built-in Administrators group on a current computer (the one where the ap

Answer 1

If you are talking about the currently running user then

using System.Security.Principal;

WindowsIdentity identity = WindowsIdentity.GetCurrent();
WindowsPrincipal wp = new WindowsPrincipal(identity);

if (wp.IsInRole("BUILTIN\Administrators"))
   // Is Administrator
else
   // Is Not

If not then I expect its possible to set identity to a particular user but not looked into how.