Introduction

Welcome to Real World .NET Applications. This book presents six "real" mediumsized software projects that contain about 1,500 lines of code each—not simply toy applications that have little or no use. Each application matches (or is close to) commercial software. But the main purpose of the applications is to teach how to design and develop .NET applications. As such, each chapter gives the reader enough background information of the technologies used in the application. All chapters give sample code that explains the techniques before discussing the application. However, for reading convenience, the text is concise. Also, not surprisingly, you will see several popular design patterns that you may have used in other projects. I have tested all applications developed for this book with the .NET Framework versions 1.0 and 1.1.

Each chapter has the following general structure:

• An introduction to supporting theories/technologies to give you enough background knowledge to understand the application

• A simple application that illustrates relevant techniques and technologies

• A class diagram containing the project's classes and their relationships

• A detailed description of the types (classes, interfaces, and structures) used in the project

• A detailed description of each member of the types used in the project

Overview of Each Chapter

The following sections give an overview of each chapter.

Chapter 1: Creating a Custom Control: StyledTextArea

This chapter teaches you how to create Windows controls by extending the System.Windows.Forms.Control class, and it teaches you several aspects of Windows custom control programming. This chapter covers the following topics:

• Using Windows controls in general

• Drawing a control's Graphical User Interface (GUI)

• Capturing key presses

• Using delegates

• Creating custom events

• Understanding the Observer design pattern

• Understanding the Model-View-Controller (MVC) paradigm

• Creating carets

• Using the System.Threading.Thread class

Chapter 2: Building an XML Document Editor

This chapter discusses a Multiple Document Interface (MDI) application that can be used to edit Extensible Markup Language (XML) documents. This chapter covers the following topics:

• Introducing a brief theory of XML

• XML programming in the .NET Framework

• Understanding the Singleton design pattern

• Printing in the .NET Framework

• Using the XMLViewer component

Chapter 3: Writing Games

This chapter explains the theory of games in general and how to write the game Doggie (a Pac-Man clone). This chapter covers the following topics:

• Working with threads

• Creating a news ticker application

• Using a timer

• Understanding game theory

Chapter 4: Creating a UML Class Diagram Editor

This chapter teaches how to write a Unified Modeling Language (UML) class diagram editor to draw and edit class diagrams. This chapter covers the following topics:

• Basic and advanced drawing in the .NET Framework

• Creating a vector-based drawing application

• Understanding object serialization

• Understanding the Memento design pattern

• Introducing a brief theory of UML

Chapter 5: Developing an FTP Client Application

This chapter explains how to use sockets in a File Transfer Protocol (FTP) client application. This chapter covers the following topics:

• Networking with the .NET Framework in general

• Using sockets

• Using FTP

Chapter 6: Building an Online Store

This chapter explains ASP.NET and ADO.NET in general and uses them and other related technologies to develop an online store. This chapter covers the following topics:

• Using ASP.NET

• Using ADO.NET

• Using Web controls

• Configuring security

• Managing session state