Echelon OpenLNS - Manual (Page 366)

OpenLNS Programmer's Reference 329
CategoryPreferenceList
Summary Establishes the format to be used when displaying the
formatted value of a data point whose default type contains
several alternate formats, such as SNVT_press.
OpenLNS will initially choose the format to use for data
points like this based on the setting of the MeasurementUnits
property. This allows you to choose between U.S. or SI metric
measurement units.
You can also use localized formats whenever possible by
writing to the CategoryPreferenceList property. In this case,
OpenLNS will first determine whether to use U.S. or SI
metric formatting by reading the MeasurementUnits
property. It will then use the CategoryPreferenceList property
to determine if it should use the localized alternate formats
that are available. If the CategoryPreferenceList property is
not set, OpenLNS will use the first alternate format it finds
that complies with the setting of the MeasurementUnits
property.
For example, consider a case where a data point is using the
SNVT_hvac_overid type. If the MeasurementUnits property
is set to use U.S. units, and the CategoryPreferenceList
property is not set, OpenLNS will use the
SNVT_hvac_overid#US format to display the value of the
data point. However, if the CategoryPreferenceList property is
set to "LO", OpenLNS will use the
SNVT_hvac_overid#US_LO format to display the value.
Consider another case where a data point is using the
SNVT_press type and the MeasurementUnits property is
set to use metric measurement units. If the
CategoryPreferenceList property is not set, OpenLNS will use
the SNVT_press#SI format to display the value of the data
point. If the CategoryPreferenceList property is set to "kPa",
OpenLNS will use the SNVT_press#SI_kPa format to
display the value of the data point.
This feature may also applies types that do not have separate
U.S. or SI metric formats but still have localized alternate
formats, such as SNVT_alarm. For example, if a data point
is using the SNVT_alarm type and the
CategoryPreferenceList is set to "LO", OpenLNS will use the
SNVT_alarm#LO format to display the value of the data
point. If the CategoryPreferenceList is not set to "LO",
OpenLNS will use the SNVT_alarm format.
In many cases, your application may need to display the
values of data points that use different types. As a result, you
can specify multiple alternate formats for a FormatLocale by
passing them to the CategoryPreferenceList property in a
comma-separated list. For example, you could set the
CategoryPreferenceList to "LO,psi" to cause LNS to look for
those alternate formats whenever possible. OpenLNS will