In .NET/C# test if user is an administrative user

Question

Is there a canonical way to test to see if a user has administrative privileges on a machine?

I'm going to be starting a long running process, and much later in the process' lifetime it's going to attempt some things that require admin privileges.

I'd like to be able to test up front if the user has those rights rather than later on.

Answer 1

This will check if user is in the local Administrators group (assuming you're not checking for domain admin permissions)

using System.Security.Principal;

public bool IsUserAdministrator()
{
    //bool value to hold our return value
    bool isAdmin;
    try
    {
        //get the currently logged in user
        WindowsIdentity user = WindowsIdentity.GetCurrent();
        WindowsPrincipal principal = new WindowsPrincipal(user);
        isAdmin = principal.IsInRole(WindowsBuiltInRole.Administrator);
    }
    catch (UnauthorizedAccessException ex)
    {
        isAdmin = false;
    }
    catch (Exception ex)
    {
        isAdmin = false;
    }
    return isAdmin;
}

Answer 2

Use can use WMI with something like this to find out if the account is an admin, and just about anything else you want to know about there account

using System;
using System.Management;
using System.Windows.Forms;

namespace WMISample
{
    public class MyWMIQuery
    {
        public static void Main()
        {
            try
            {
                ManagementObjectSearcher searcher = 
                    new ManagementObjectSearcher("root\\CIMV2", 
                    "SELECT * FROM Win32_UserAccount"); 

                foreach (ManagementObject queryObj in searcher.Get())
                {
                    Console.WriteLine("-----------------------------------");
                    Console.WriteLine("Win32_UserAccount instance");
                    Console.WriteLine("-----------------------------------");
                    Console.WriteLine("AccountType: {0}", queryObj["AccountType"]);
                    Console.WriteLine("FullName: {0}", queryObj["FullName"]);
                    Console.WriteLine("Name: {0}", queryObj["Name"]);
                }
            }
            catch (ManagementException e)
            {
                MessageBox.Show("An error occurred while querying for WMI data: " + e.Message);
            }
        }
    }
}

To make it easier to get started download WMI Creator

you can also use this it access active directory (LDAP) or anything else on you computer/network

Answer 3

If you want to make sure your solution works in Vista UAC, and have .Net Framework 3.5 or better, you might want to use the System.DirectoryServices.AccountManagement namespace. Your code would look something like:

bool isAllowed = false;
using (PrincipalContext pc = new PrincipalContext(ContextType.Machine, null))
{
    UserPrincipal up = UserPrincipal.Current;
    GroupPrincipal gp = GroupPrincipal.FindByIdentity(pc, "Administrators");
    if (up.IsMemberOf(gp))
        isAllowed = true;
}