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Table Of Contents
Programming Windows Workflow Foundation: Practical WF Techniques and Examples using XAML and C#
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The declarative rule conditions we've seen in the previous sections only return a value of true or false. A condition doesn't modify a workflow. A rule, on the other hand, is both a condition and a set of actions in an if-then-else form. The Rule class in Windows Workflow represents this if-then-else concept. The class diagram in the following screenshot displays classes with important relationships to the Rule class.

The first concept to notice is that the RuleSet class manages a collection of rules. The Policy activity will use the Execute method of a RuleSet to process the rule collection. We will cover the Policy activity in more detail soon.
Every Rule inside a RuleSet has a Condition property that references a single RuleCondition object. The RuleSet logic will use the Evaluate method of a RuleCondition to retrieve a value of true or false.
Every Rule maintains two collections of RuleAction objects—the ElseActions and the ThenActions. When a rule's condition evaluates...
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