Thetype exposes the following members.
Gets the name used to create the ITopicDescription.(Inherited from TopicDescription.)
Gets the subscription expression associated with the. That is, the expression specified when the was created.
Gets type name used to create the ITopicDescription.(Inherited from TopicDescription.)
Determines whether the specified object is equal to the current object.(Inherited from Object.)
Gets the expression parameters associated with the SetExpressionParameters(String), or if it was never called, the parameters specified when the was created.. That is, the parameters specified on the last successful call to
Serves as the default hash function.(Inherited from Object.)
Gets the Type of the current instance.(Inherited from Object.)
Changes the expression parameters associated with the.
Returns a string that represents the current object.(Inherited from Object.)
The subscription expression is a string that identifies the selection and re-arrangement of data from the associated topics. It is similar to an SQL clause where the SELECT part provides the fields to be kept, the FROM part provides the names of the topics that are searched for those fields, and the WHERE clause gives the content filter.The topics combined may have different types but they are restricted in that the type of the fields used for the NATURAL JOIN operation must be the same.
The expression parameters are a collection of strings that give values to the ‘parameters’ ("%n" tokens) in the subscription expression. The number of supplied parameters must fit with the requested values in the subscription expression (the number of %n tokens).
DataReader entities associated with a MultiTopic are alerted of data modifications by the usual listener or condition mechanisms whenever modifications occur to the data associated with any of the topics relevant to the MultiTopic.
DataReader entities associated with a MultiTopic access instances that are “constructed” at the DataReader side from the instances written by multiple DataWriter entities.The MultiTopic access instance will begin to exist as soon as all the constituting Topic instances are in existence.
The view_state and instance_state is computed from the corresponding states of the constituting instances: