System.Security.SecurityException.ToStringHelper C# (CSharp) Method

        private void ToStringHelper(StringBuilder sb, String resourceString, Object attr)
        {
            if (attr == null)
                return;
            String attrString = attr as String;
            if (attrString == null)
                attrString = attr.ToString();
            if (attrString.Length == 0)
                return;
            sb.Append(Environment.NewLine);
            sb.Append(GetResString(resourceString));
            sb.Append(Environment.NewLine);
            sb.Append(attrString);
        }