About the Use Free Form, Data Type, and Format properties

Data type and format definitions for components that have the Use Free Form property enabled are specified with the Data Type property and the Format property, rather than with the properties normally used.

Definitions consist of keywords and parameters. The use of keywords allows you to specify substitution keywords rather than literal values as parameters. Variable values can be set programmatically through the application and retrieved as keyword parameters at run time.

Component classes and property class extensions

In a component class or property class extension, Data Type and Format values are combined like this:

keyword1 ( parameter ) [keyword2 ( parameter ) . . . keywordn ( parameter ) ] DEFAULTFORMAT ( keyword1 ( parameter ) [ keyword2 ( parameter ) . . . keywordn ( parameter ) ] )

Note: All format keywords are specified as parameters to the DEFAULTFORMAT keyword.

Examples

In this definition from a component class, parameters of the keywords are temporary, global variables.


DATATYPE(V(AcctDataType))LENGTH(V(AcctLength))DEFAULTFORMAT(MASK(V(AcctInputMask))JUSTIFY(V(AcctJustify)))

Values of the variables are set at system startup by an IDO method call. At run time, the expression evaluates to this:


DATATYPE(NUMSORTCHAR)LENGTH(5))DEFAULTFORMAT(MASK(ZZZZZ))JUSTIFY(R))

In the properties sheet for the component class, NUMSORTCHAR appears as the Underlying Type, and 5 appears as the Length. The Input Mask value is ZZZZZ, and the Justification property is Right. All values are read-only.