Lesson 7. Basic .Net libraries. Strings and regular expressions.
Objective: is to develop a holistic understanding of callback mechanisms and the event-driven programming model in the .NET environment. The student must master the concept of a delegate as a type-safe object that points to methods, and understand the role of delegates as the foundation for implementing events. During the training, special attention is paid to understanding the syntax of declaring, initializing, and calling delegates, as well as studying the capabilities of group addressing (multicasting) for sequentially executing several methods with a single call. Students must master practical skills in creating event models, where an event is considered as a means of informing observer objects about a change in the state of the source object, which allows implementing the principle of weak coupling of system components. An important aspect is the study of the standard event development pattern in .NET, including the use of the EventHandler delegate and passing data via EventArgs. In addition, the course provides for familiarization with anonymous methods and lambda expressions as modern ways to simplify code when working with delegates. In conclusion, the student should be able to analyze application architecture for the effective implementation of event mechanisms, ensuring flexibility and extensibility of the software.