Features

Features (or variables) store values. In most cases, they can be created as scalar for storing a single value and as a list for storing a set of values in list indexes.

There are a number of different types of features:

Type	Description
Boolean	Stores NoValue, True (-1), False (0)
Long	Stores 32-bit signed integer number
Double	Stores 64-bit floating point number
Date	Stores a date and time
Currency	Stores a currency
String	Stores a unicode string
Variant	Stores alls kinds of data types, objects included
RTF	Stores a Rich Text Format text
PDF	Stores a PDF document
Picture	Stores a twodimensional raster image or vector image (EMF)
Model3D	Stores a threedimensional model
TCE Object Pointer	Stores a reference (pointer) of a TCE object
COM Reference	Stores a reference of a COM object (IDispatch)
Reference	Stores a relative path of an object or feature and evaluates this path
Formular	Reference of a form to display windows or parts of windows
Control	Reference of a control container for controls in forms
Menu	Reference of a menu
Class	Reference of a class in the class structure oft he knowledge base
Font	Reference of a font
Toolbar	Reference of a toolbar
Connection	Reference to a database connection
	Reference to a fuzzy diagram for statistical rules
Table	Reference to a database table object

Each feature type has specific properties. These properties can be defined in part at the time of design.

Property	Description
Type	The type of feature.
Overrideable	The feature can be overdefined and changed in derived classes.
List	If the switch is set, the feature is as list.
Enabled	If the switch is not set, an expression can be entered, which controls the activation of many controls.
Visible	If the switch is not set, an expression can be entered, which controls the visibility of many controls.
Multi language format	Once the switch is set, a format can be specified for each language defined in the knowledge base instead of monolingual formatting of the value of the characteristic. Format
Format	It is possible to specify a formatting of the value of the feature for all languages of the knowledge base. Format
Description	An expression can be stored which determines the name of the characteristic. For multilingual knowledge bases, a text constant makes sense here.
Initialise with standard value	Certain features can have a default value, which is used instead of NoValue when the switch is set. Boolean: False Long: 0 Double: 0 String: ''
Save	When the switch is set, the value of the feature is stored in serialized object trees. For example, serialized object trees can be used to save an object structure as a file.
Initialize on change of object	While changing the class of the object from A to B, TCE is trying to maintain the value of characteristics defined in both classes A and B. If, in the case of such an object change, reinitialization of the feature is needed, this switch must be set.
Rules	If this switch is set, defined possible values for the feature can be provided with validity rules. On every time the interpreter has an empty method stack and a rule check of all objects is executed, this feature will be proven.
Check rules on change	If this switch is set, a new rules check is triggered by changing the feature value. Otherwise, this will not occur and only one client update will be made if necessary.
Assign valid value	If the validation determines exactly one valid value, this value is assigned to the feature.
Multi language	If the switch is set, the feature maintains a value for each language defined in the knowledge base.
Initialize with database value	If the class is a class defining ODBC classes, the characteristic can be initialized with a value of a column in the SELECT statement of the ODBC selection. The DB column can then be specified for each language ID of the knowledge base, if the switch “Multi language” is set.
Tag	Free string content
Use currency factors	The conversion factors for currencies are stored in the properties of the knowledge base. If the feature is to use these factors, this switch can be set. The conversion factors are proposed for all defined currencies. However, the expressions can be changed. If the switch is not set, it must be ensured that all currency containers of the characteristic receive matching values.
Use events	If this switch is activated, the event interface is activated for the underlying object (e.g. COM objects) and the defined events can be processed.
TCE class	TCE object pointers require specifying the TCE class to allow syntactic verification of the pointer.
Class	COM object pointers require specifying the COM class

Initializations

Example of an initialization for a non-list feature (scalar feature)

Characteristics are initialized with a valid expression. Initialization must match the feature type.

Decision

By clicking on the symbol, a new decision can be created for the feature.

Setting valid values

When the Rules switch is set, values can be added to the feature using the context menu for setting the operator.

Action	Description
Apply	Different operators can be selected. = Equal <> Not equal >= Greater equal > Greater <= Lower equal < Lower Like match search In Presence in list or range NotIn Absence in list or range IsA Checking for class type NotIsA Check for class type (negated) Pick list A picklist for selection controls
Initial value	The value is taken as the initial value.
New	A new value is created in the value pool
Change	An existing value in the value pool can be changed
Delete	Deleting an existing value in the value pool
Override	A value in the value pool can be overridden

Possible value

Decision

Events for features