Class Properties

The Visual Basic property window for the class module is where the CML development team defines much of the behavior of each component.

Class properties for CML objects are:

DataBindingBehavior

Sets a value that determines if an object can be bound to a data source. All CML classes use the default of vbNone because the object will not be bound to a data source.

DataSourceBehavior

Sets a value that determines if an object can act as a source of data for other objects. All CML classes use the default of vbNone because the objects are never sources of data for other objects.

Instancing

Sets a value that specifies whether you can create instances of a public class outside a project, and if so, how it will behave. CML classes UserInfo, User, Admin, and Search use the instance property value MultiUse. This allows other applications to create objects from the class. One instance of your component can provide any number of objects and the objects will be provided by the same instance of the component. MultiUse is more efficient with memory because it prevents additional copies of the component from being executed.

The TableQueue and MTSEnvironment class instance property value is Private. Other applications cannot see any of the interfaces provided by the class or create objects from the class. Objects can only be created within the component that contains the class. Support classes such as TableQueue and MTSEnvironment are usually Private. About the TableQueue Object describes how the TableQueue component is different from other CML components.

MTSTransactionMode

Specifies the transactional behavior of a class. This property is only used by components running in Microsoft Transaction Server. The transactional behavior of each CML component is a reflection of the tasks the component performs. See Designing the CML Components and Objects for a detailed description of component functionality.

Transactional behaviors:

• Admin class is RequiresTransactions.
• UserInfo class is NoTransactions.
• Search class is NoTransactions.
• User class is UsesTransactions.
• TableQueue and MTSEnvironment classes are private and the MTSTransactionMode property does not apply.

Persistable

Sets a value that determines if an object can save and restore data across instances. The Admin, User, UserInfo, and Search classes have the value NotPersistable. The TableQueue and MTSEnvironment classes are private and this property does not apply.

The business logic of the CML application is implemented with the methods and properties of the class modules contained in CML.dll and CMLC.dll.