Check if user is elevated (UAC)

gistfile1.txt

// copied from :
// http://stackoverflow.com/a/17492949/305135

public static class UacHelper
{
    private const string uacRegistryKey = "Software\\Microsoft\\Windows\\CurrentVersion\\Policies\\System";
    private const string uacRegistryValue = "EnableLUA";

    private static uint STANDARD_RIGHTS_READ = 0x00020000;
    private static uint TOKEN_QUERY = 0x0008;
    private static uint TOKEN_READ = (STANDARD_RIGHTS_READ | TOKEN_QUERY);

    [DllImport("advapi32.dll", SetLastError = true)]
    [return: MarshalAs(UnmanagedType.Bool)]
    static extern bool OpenProcessToken(IntPtr ProcessHandle, UInt32 DesiredAccess, out IntPtr TokenHandle);

    [DllImport("kernel32.dll", SetLastError = true)]
    [return: MarshalAs(UnmanagedType.Bool)]
    static extern bool CloseHandle(IntPtr hObject);

    [DllImport("advapi32.dll", SetLastError = true)]
    public static extern bool GetTokenInformation(IntPtr TokenHandle, TOKEN_INFORMATION_CLASS TokenInformationClass, IntPtr TokenInformation, uint TokenInformationLength, out uint ReturnLength);

    public enum TOKEN_INFORMATION_CLASS
    {
        TokenUser = 1,
        TokenGroups,
        TokenPrivileges,
        TokenOwner,
        TokenPrimaryGroup,
        TokenDefaultDacl,
        TokenSource,
        TokenType,
        TokenImpersonationLevel,
        TokenStatistics,
        TokenRestrictedSids,
        TokenSessionId,
        TokenGroupsAndPrivileges,
        TokenSessionReference,
        TokenSandBoxInert,
        TokenAuditPolicy,
        TokenOrigin,
        TokenElevationType,
        TokenLinkedToken,
        TokenElevation,
        TokenHasRestrictions,
        TokenAccessInformation,
        TokenVirtualizationAllowed,
        TokenVirtualizationEnabled,
        TokenIntegrityLevel,
        TokenUIAccess,
        TokenMandatoryPolicy,
        TokenLogonSid,
        MaxTokenInfoClass
    }

    public enum TOKEN_ELEVATION_TYPE
    {
        TokenElevationTypeDefault = 1,
        TokenElevationTypeFull,
        TokenElevationTypeLimited
    }

    public static bool IsUacEnabled
    {
        get
        {
            using (RegistryKey uacKey = Registry.LocalMachine.OpenSubKey(uacRegistryKey, false))
            {
                bool result = uacKey.GetValue(uacRegistryValue).Equals(1);
                return result;
            }
        }
    }

    public static bool IsProcessElevated
    {
        get
        {
            if (IsUacEnabled)
            {
                IntPtr tokenHandle = IntPtr.Zero;
                if (!OpenProcessToken(Process.GetCurrentProcess().Handle, TOKEN_READ, out tokenHandle))
                {
                    throw new ApplicationException("Could not get process token.  Win32 Error Code: " +
                                                   Marshal.GetLastWin32Error());
                }

                try
                {
                    TOKEN_ELEVATION_TYPE elevationResult = TOKEN_ELEVATION_TYPE.TokenElevationTypeDefault;

                    int elevationResultSize = Marshal.SizeOf((int) elevationResult);
                    uint returnedSize = 0;

                    IntPtr elevationTypePtr = Marshal.AllocHGlobal(elevationResultSize);
                    try
                    {
                        bool success = GetTokenInformation(tokenHandle, TOKEN_INFORMATION_CLASS.TokenElevationType,
                                                           elevationTypePtr, (uint) elevationResultSize,
                                                           out returnedSize);
                        if (success)
                        {
                            elevationResult = (TOKEN_ELEVATION_TYPE) Marshal.ReadInt32(elevationTypePtr);
                            bool isProcessAdmin = elevationResult == TOKEN_ELEVATION_TYPE.TokenElevationTypeFull;
                            return isProcessAdmin;
                        }
                        else
                        {
                            throw new ApplicationException("Unable to determine the current elevation.");
                        }
                    }
                    finally
                    {
                        if (elevationTypePtr != IntPtr.Zero)
                            Marshal.FreeHGlobal(elevationTypePtr);
                    }
                }
                finally
                {
                    if (tokenHandle != IntPtr.Zero)
                        CloseHandle(tokenHandle);
                }
            }
            else
            {
                WindowsIdentity identity = WindowsIdentity.GetCurrent();
                WindowsPrincipal principal = new WindowsPrincipal(identity);
                bool result = principal.IsInRole(WindowsBuiltInRole.Administrator) 
                           || principal.IsInRole(0x200); //Domain Administrator
                return result;
            }
        }
    }
}