System.Security.FrameSecurityDescriptor.HasImperativeRestrictions C# (CSharp) Method

        internal bool HasImperativeRestrictions() 
        {
            // we store declarative actions in both fields, so check if they are different
            return (m_restriction != null);
        }
        internal void SetAssert(IPermission perm)

        internal static void PermitOnly(PermissionSet permSet, ref StackCrawlMark stackMark)
        {
            FrameSecurityDescriptor securityObjectForFrame = SecurityRuntime.GetSecurityObjectForFrame(ref stackMark, true);

            if (securityObjectForFrame == null)
            {
                Environment.FailFast(Environment.GetResourceString("ExecutionEngine_MissingSecurityDescriptor"));
                return;
            }
            if (securityObjectForFrame.HasImperativeRestrictions())
            {
                throw new SecurityException(Environment.GetResourceString("Security_MustRevertOverride"));
            }
            securityObjectForFrame.SetPermitOnly(permSet);
        }