C# Class Examples.ClientConsumingRecordTopics

This demonstrates a client consuming record topics and reading the content using a structured reader. This makes use of the 'Topics' feature only. To subscribe to a topic, the client session must have the 'read_topic' permission for that branch of the topic tree. This example receives updates to currency conversion rates via a branch of the topic tree where the root topic is called 'FX'; beneath which is a topic for each base currency, and beneath each of those is a topic for each target currency which contains the bid and ask rates. So a topic 'FX/GBP/USD' would contain the rates for GBP to USD. This example maintains a local dictionary of the rates and also notifies a listener of any rates changes. The example shows the use of empty fields. Any of the rates can be empty (meaning the rate is not available in this example), so it can be an empty string in the topic value. Because delta updates use a zero-length string to indicate that a field has not changed, a special 'empty field' value is used to indicate that the field has changed to empty in deltas. The client application must therefore convert empty string values to "" for the local rate value.