Expression Objects
An expression is a statement constructed with Boolean and relational operators that is evaluated against the data in a given set of profiles, also known as the evaluation context of the expression. The profiles may be ProfileObject objects, Dictionary objects, or other objects that support property access through the IDispatch interface. Expressions always evaluate to either True or False.
The Expression Architecture consists of three major components: the Expression Store, the Expression Builder, and the Expression Evaluator Engine (EEE). The Expression Store consists of a set of database tables that store the expressions along with related information such as the expression ID and name. For more information, see Expression Recordset.
The Expression Builder provides a Web-based user interface, which allows the business manager to create, modify, and view expressions. For more information, see Expression Builder.
The EEE is the component of most interest to the developer. The EEE is a Component Object Model (COM) object used for evaluating expressions. It uses the services of the ExpressionStore object to load the expressions before evaluating them. It also creates evaluation contexts that are used to evaluate a set of expressions against the same profiles in the most efficient manner. The EEE is used by the marketing and campaign components of Commerce Server 2000.
This topic contains:
Expression Programming Concepts. Describes the EEE and the objects it exposes.
Example Code for Expression Objects. Provides detailed examples of how to use the objects exposed by the EEE.