UDA Lists of Values

User-Defined Attributes (UDAs) and User System Defined Attributes (USDAs) can have a list of valid values (for text attributes) or a list of valid ranges (for numeric attributes). These lists are checked when setting the UDA to prevent the use of values outside the valid range.

A new logical attribute on UDA and USDA elements determines whether the valid values or ranges (if such exist) are optional. The default behaviour remains that the restrictions remain non-optional. If, however, this attribute is set TRUE and the UDA or USDA definition is re-compiled, it will be possible to override the restriction and set the attribute to a value outside the valid range.

To support this, a new method has been added to PML2 Attribute object and .NET public interface.

The new method LIMITSVALIDOPTIONAL(ELEMENTTYPE) complements the existing LIMITS(ELEMENTTYPE) and VALIDVALUES(ELEMENTTYPE) methods.

The .NET database interface class for attributes, Aveva.Pdms.Database.DbAttribute has a new method to determine whether the valid values or range is optional for a particular element type:

public abstract bool IsAllowedOptional(DbElementType type);