/// <summary>
        /// Checks that a frame is correctly constructed.
        /// </summary>
        /// <param name="nodeType">Type of the node this frame can describe.</param>
        /// <param name="nodeTemplateTable">Table of templates with all frames.</param>
        /// <param name="commentFrameCount">Number of comment frames found so far.</param>
        public override bool IsValid(Type nodeType, FrameTemplateReadOnlyDictionary nodeTemplateTable, ref int commentFrameCount)
        {
            bool IsValid = true;

            IsValid &= base.IsValid(nodeType, nodeTemplateTable, ref commentFrameCount);
            IsValid &= !string.IsNullOrEmpty(PropertyName) && NodeTreeHelper.IsProperty(nodeType, PropertyName);

            Debug.Assert(IsValid);
            return(IsValid);
        }