Opc.Ua.ReadValueId.Validate C# (CSharp) Method

        public static ServiceResult Validate(ReadValueId valueId)
        {
            // check for null structure.
            if (valueId == null)
            {
                return StatusCodes.BadStructureMissing;
            }

            // null node ids are always invalid.
            if (valueId.NodeId == null)
            {
                return StatusCodes.BadNodeIdInvalid;
            }
            
            // must be a legimate attribute value.
            if (!Attributes.IsValid(valueId.AttributeId))
            {
                return StatusCodes.BadAttributeIdInvalid;
            }
            
            // data encoding and index range is only valid for value attributes. 
            if (valueId.AttributeId != Attributes.Value)
            {
                if (!String.IsNullOrEmpty(valueId.IndexRange))
                {
                    return StatusCodes.BadIndexRangeNoData;
                }

                if (!QualifiedName.IsNull(valueId.DataEncoding))
                {
                    return StatusCodes.BadDataEncodingInvalid;
                }
            }

            // initialize as empty.
            valueId.ParsedIndexRange = NumericRange.Empty;

            // parse the index range if specified.
            if (!String.IsNullOrEmpty(valueId.IndexRange))
            {
                try
                {
                    valueId.ParsedIndexRange = NumericRange.Parse(valueId.IndexRange);
                }
                catch (Exception e)
                {
                    return ServiceResult.Create(e, StatusCodes.BadIndexRangeInvalid, String.Empty);
                }
            }
            else
            {
                valueId.ParsedIndexRange = NumericRange.Empty;
            }

            // passed basic validation.
            return null;
        }
        #endregion