Coding In Delphi
Coding In Delphi
About the Book
Over the years, I've spoken in front of a lot of Delphi developers. The one thing that I notice is that there are a lot more of you Delphi guys than the average Delphi guy thinks. There are Delphi folks everywhere. Also, I have noticed that a lot of Delphi developers are "behind". That is, they are either using an older version of Delphi, or they aren't using or aren't even aware of all the features in the newer versions of Delphi that they are using. Something I like to do when I'm in front of folks is ask a few questions about what people are doing. I'm always saddened that the response to questions like "Who is doing unit testing?" or "Who is taking advantage of Generics?" is pretty meager.
This is particularly true for the language features and the run-time library. It's quite easy to move forward with an older code base, utilizing the new features in the IDE and adding new things to your app using the new high level frameworks and components that come in the newer versions. For example, you might have been developing an application since Delphi 3, moving forward through various versions. Along the way, you may have added some DataSnap functionality, started using the Code Insight features in the IDE, and when you moved to XE2, you start poking around with FireMonkey.
But it's fairly easy to ignore the new language features that come along with those new versions. For instance, two powerful language features were added in Delphi 2009: generics and anonymous methods. Both are features that enable the development of really cool code and frameworks. But if you didn't understand or feel the need for them, then it was pretty easy to simply not use them. You can still do all kinds of great stuff in Delphi without them, but with them, well, you can write some really beautiful, testable, and amazing code.
For instance, a relatively new framework that exists only because of these new language features is the Spring Framework for Delphi, or Spring4D, as I'll refer to it in this book. Spring4D is a feature rich framework that provides a number of interesting services, including a wide variety of collections that leverage generics, an Inversion of Control container, encryption support, and much more. I view Spring4Dsolid as much a part of the Delphi RTL as SysUtils is. Using Spring4D in your code will make many, many things easier and cleaner. But many Delphi developers don't know this yet.
If the above is familiar, this book is for you: The Delphi developer that hasn't quite yet made the leap over into the cool and amazing things that you can do with the latest versions of the Delphi language. This book is all about introducing these new language features and some of the intriguing things you can do with them. It will take a look at these new language features, and then expand into some of the open source frameworks that have sprung up (no pun intended) as a result. It will then show you techniques that you can use to write [SOLID](http://butunclebob.com/ArticleS.UncleBob.PrinciplesOfOod), clean, testable code.
You won't find much of anything about the IDE or the higher level frameworks here. Screen shots will be few but code examples many. You won't find anything about how to build better user interfaces or fancy components. What you will find are ways to make your code much cleaner, much more powerful, and way easier to maintain.
This book is all about the cool, new code you can write with Delphi. It won't matter whether you are building a VCL or an FM application. I've titled it "Coding in Delphi" because I want to make it a book that shows you simple examples of how to use powerful features -- that, is about the *code*. These language features are indeed advanced features -- they are new relative to, say, the `case` statement -- and thus many of you are beginners to them. By the end of this book, you won't be.
The approach I'm taking for this book is to try to distill things down to the very basics. The examples will be very simple but the explanations deeper. I believe that if you can understand the basic idea in a simple example, it is but a small leap to using those ideas in more complex code. There is no point in giving complex examples when you can get the main thrust using fundamental implementations that illustrate advanced ideas. Between the code in this book and in the samples online ([https://bitbucket.org/NickHodges/codingindelphi](https://bitbucket.org/NickHodges/codingindelphi)) you can learn all the precepts and then begin applying them to your own code. In other words, nothing fancy here, just the basics -- it is then up to you to use these ideas in your own code.
This book is not done -- it's instead a living document. Since it is self-published on a platform that makes iteration very easy, I plan on having frequent releases to fix typos (which will, I'm sure, sneak through despite my best efforts), improve examples and descriptions, and keep up with technology changes. Owners of the PDF should get notifications of new versions automatically. If you are reading a paper version of this book, I'm sorry I can't deliver fixes to your hard-copy -- perhaps some day that will be possible.
The book will be done when you guys say it is done. Maybe, it will never be done because Delphi keeps growing and expanding. I guess we'll see.
As a result, I'm totally open to feedback -- please feel free to contact me at nickhodges@gmail.com with suggestions corrections, and improvements. Please join [the Google Plus group for the book.](https://plus.google.com/communities/110978417023349293804) I may even add whole new chapters.
Thanks for your purchase -- this book was a labor of love, so every sale is icing on the cake.
Nick Hodges
Gilbertsville, PA
Bundles that include this book
Table of Contents
- Foreword
- Introduction
- Acknowledgements
-
Frameworks used in Coding in Delphi
- Delphi Spring Framework
- DUnitX
- Delphi Mocks
- DSharp
-
1 Exceptions and Exception Handling
- 1.1 Introduction
- 1.2 Structured Exception Handling
- 1.3 How Not to Use Exceptions
- 1.4 How to Use Exceptions Properly
- 1.5 Conclusion
-
2 Using Interfaces
- 2.1 Introduction
- 2.2 Decoupling
- 2.3 What are Interfaces?
- 2.4 Interfaces Everywhere
- 2.5 A Simple Example
- 2.6 Implementing an Interface
- 2.7 Some Further Things to Note:
- 2.8 Interface Inheritance
- 2.9 Other Things to Think About
- 2.10 About TInterfacedObject
- 2.11 How to Actually Use Interfaces
- 2.12 Why Should You Be Using Interfaces?
-
3 Understanding Generics
- 3.1 Generics to the Rescue
- 3.2 Constraints
- 3.3 Generic Interfaces
- 3.4 Generic Methods
- 3.5 Generic Collections
- 3.6 Thinking Generically
- 3.7 A Contrived, Simple Example
- 3.8 A Practical Example
- 3.9 Conclusion
- 3.10 An Interview with Generics
-
4 Understanding Anonymous Methods
- 4.1 Introduction
- 4.2 Definition
- 4.3 Why?
- 4.4 Closures
- 4.5 Standard Declarations
- 4.6 A Practical Example
- 4.7 Another, Cooler Example
- 4.8 Anonymous methods in the RTL
- 4.9 Predicates
- 4.10 Conclusion
- 4.11 An Interview with Anonymous Methods
-
5 Delphi Collections
- 5.1 Introduction
- 5.2 General Notions about Collections
- 5.3 The Delphi-Provided Collections
-
5.4
TQueue<T>
- 5.5 Collections in the Delphi Spring Framework
- 5.6 Why you should be using the Spring4D Collections
- 5.7 Conclusion
-
6 Enumerators in Delphi
- 6.1 Introduction
-
6.2
IEnumerator<T>
Interface - 6.3 Specialized Enumerators
-
6.4
TEnumerable<T>
in Generics.Collections - 6.5 Conclusion
-
7 IEnumerable<T />
-
7.1
IEnumerable<T>
- 7.2 Predicates
-
7.3 An Interview with
IEnumerable<T>
(IEoT):
-
7.1
-
8 Run-time Type Information
- 8.1 Introduction
-
8.2
TValue
- 8.3 RTTI on Classes
- 8.4 Using RTTI to Affect Instances
- 8.5 General Notes
- 8.6 RTTI for Non-classes
- 8.7 Miscellaneous Methods
- 8.8 RTTI Compiler Directives
- 8.9 Conclusion
-
9 Attributes
- 9.1 Introduction
- 9.2 What are Attributes
- 9.3 A Simple Example
- 9.4 Conclusion
- 9.5 An Interview with Attributes
-
10 Using TVirtualInterface
- 10.1 A Slightly Better TVirtualInterface
- 10.2 An Actually Useful Example
- 10.3 ISimpleStub
- 10.4 TSimpleMock
- 10.5 Conclusion
-
11 Introduction to Dependency Injection
- 11.1 Introduction
- 11.2 What is a Dependency?
- 11.3 The Law of Demeter (LoD)
- 11.4 A Design Example
- 11.5 Law of Demeter in Delphi
- 11.6 A Step-by-Step Code Example
- 11.7 The Dependency Injection Container
- 11.8 Conclusion
-
12 A Deeper Look at Dependency Injection
- 12.1 Optional Dependencies
- 12.2 Setter Injection
- 12.3 Method Injection
- 12.4 The Delphi Spring Container and Service Locator
- 12.5 Registering via attributes
-
12.6
ServiceLocator
as Anti-pattern - 12.7 Dependency Injection Summary
-
13 Unit Testing
- 13.1 So What is Unit Testing?
- 13.2 Why Do Unit Testing?
- 13.3 Unit Testing in Delphi
- 13.4 General Rules for Unit Tests
- 13.5 Test Driven Development
- 13.6 A Basic Example
-
14 Testing with an Isolation Framework
- 14.1 A Quick Review
- 14.2 Isolation Frameworks for Delphi
- 14.3 Getting Started
- 14.4 Conclusion
-
Appendix A: Resources
- Dependency Injection
- Unit Testing
- Source Control
- Projects
- General Good Stuff
- Appendix B: My Delphi Story
The Leanpub 60-day 100% Happiness Guarantee
Within 60 days of purchase you can get a 100% refund on any Leanpub purchase, in two clicks.
See full terms
80% Royalties. Earn $16 on a $20 book.
We pay 80% royalties. That's not a typo: you earn $16 on a $20 sale. If we sell 5000 non-refunded copies of your book or course for $20, you'll earn $80,000.
(Yes, some authors have already earned much more than that on Leanpub.)
In fact, authors have earned$12,307,240writing, publishing and selling on Leanpub.
Learn more about writing on Leanpub
Free Updates. DRM Free.
If you buy a Leanpub book, you get free updates for as long as the author updates the book! Many authors use Leanpub to publish their books in-progress, while they are writing them. All readers get free updates, regardless of when they bought the book or how much they paid (including free).
Most Leanpub books are available in PDF (for computers) and EPUB (for phones, tablets and Kindle). The formats that a book includes are shown at the top right corner of this page.
Finally, Leanpub books don't have any DRM copy-protection nonsense, so you can easily read them on any supported device.
Learn more about Leanpub's ebook formats and where to read them
Top Books
OpenIntro Statistics
David Diez, Christopher Barr, Mine Cetinkaya-Rundel, and OpenIntroA complete foundation for Statistics, also serving as a foundation for Data Science.
Leanpub revenue supports OpenIntro (US-based nonprofit) so we can provide free desk copies to teachers interested in using OpenIntro Statistics in the classroom and expand the project to support free textbooks in other subjects.
More resources: openintro.org.
Personal Finance
Jason AndersonThis textbook provides an in-depth analysis on personal finance that is both practical and straightforward in its approach. It has been written in such a way that the readers can gain knowledge without getting overwhelmed by the technical terms. Suitable for both beginners and advanced learners.
Getting to Know IntelliJ IDEA
Trisha Gee and Helen ScottIf we treat our IDE as a text editor, we are doing ourselves a disservice. Using a combination of tutorials and a questions-and-answers approach, Getting to Know IntelliJ IDEA will help you find ways to use IntelliJ IDEA that enable you to work comfortably and productively as a professional developer.
C++20 - The Complete Guide
Nicolai M. JosuttisAll new language and library features of C++20 (for those who know previous C++ versions).
The book presents all new language and library features of C++20. Learn how this impacts day-to-day programming, to benefit in practice, to combine new features, and to avoid all new traps.
Buy early, pay less, free updates.
Other books:
Mastering STM32 - Second Edition
Carmine NovielloWith more than 1200 microcontrollers, STM32 is probably the most complete ARM Cortex-M platform on the market. This book aims to be the most complete guide around introducing the reader to this exciting MCU portfolio from ST Microelectronics and its official CubeHAL and STM32CubeIDE development environment.
R Programming for Data Science
Roger D. PengThis book brings the fundamentals of R programming to you, using the same material developed as part of the industry-leading Johns Hopkins Data Science Specialization. The skills taught in this book will lay the foundation for you to begin your journey learning data science. Printed copies of this book are available through Lulu.
Machine Learning Q and AI
Sebastian Raschka, PhDHave you recently completed a machine learning or deep learning course and wondered what to learn next? With 30 questions and answers on key concepts in machine learning and AI, this book provides bite-sized bits of knowledge for your journey to becoming a machine learning expert.
Stats One
William FooteThe Rails 7 Way
Obie Fernandez, Lucas Dohmen, and Tom Henrik AadlandThe Rails™ 7 Way is the comprehensive, authoritative reference guide for professionals delivering production-quality code using modern Ruby on Rails. It illuminates the entire Rails 7 API, its most powerful idioms, design approaches, and libraries. Building on the previous editions, this edition has been heavily refactored and updated.
Gradual Modularization for Ruby and Rails
Stephan HagemannGet yourself a new tool to manage your Rails application and your growing engineering organization! Prevent the ball-of-mud (and fix it!). Go for microservices or SOA if it makes sense not just because you don't have any other tool. Do all this through a low-overhead tool: packages. Enable better conversations to make practical changes today.
Top Bundles
- #1
Software Architecture
2 Books
"Software Architecture for Developers" is a practical and pragmatic guide to modern, lightweight software architecture, specifically aimed at developers. You'll learn:The essence of software architecture.Why the software architecture role should include coding, coaching and collaboration.The things that you really need to think about before... - #2
CCIE Service Provider Ultimate Study Bundle
2 Books
Piotr Jablonski, Lukasz Bromirski, and Nick Russo have joined forces to deliver the only CCIE Service Provider training resource you'll ever need. This bundle contains a detailed and challenging collection of workbook labs, plus an extensively detailed technical reference guide. All of us have earned the CCIE Service Provider certification... - #3
1500 QUIZ COMMENTATI (3 libri)
3 Books
Tre libri dei QUIZ MMG Commentati al prezzo di DUE! I QUIZ dei concorsi ufficiali di Medicina Generale relativi agli anni: 2000-2001-2003-2012-2013-2014-2015-2016-2017-2018-2019-2020-2021 +100 inediti Raccolti in unico bundle per aiutarvi nello studio e nella preparazione al concorso. All'interno di ogni libro i quiz sono stati suddivisi per... - #4
Pattern-Oriented Memory Forensics and Malware Detection
2 Books
This training bundle for security engineers and researchers, malware and memory forensics analysts includes two accelerated training courses for Windows memory dump analysis using WinDbg. It is also useful for technical support and escalation engineers who analyze memory dumps from complex software environments and need to check for possible... - #5
Practical FP in Scala + Functional event-driven architecture
2 Books
Practical FP in Scala (A hands-on approach) & Functional event-driven architecture, aka FEDA, (Powered by Scala 3), together as a bundle! The content of PFP in Scala is a requirement to understand FEDA so why not take advantage of this bundle!? - #6
Modern C++ Collection
3 Books
Get All about Modern C++C++ Standard Library, including C++20Concurrency with Modern C++, including C++20C++20Each book has about 200 complete code examples. Updates are included. When I update one of the books, you immediately get the updated bundle. You can expect significant updates to each new C++ standard (C++23, C++26, .. ) and also... - #7
Linux Administration Complet
4 Books
Ce lot comprend les quatre volumes du Guide Linux Administration :Linux Administration, Volume 1, Administration fondamentale : Guide pratique de préparation aux examens de certification LPIC 1, Linux Essentials, RHCSA et LFCS. Administration fondamentale. Introduction à Linux. Le Shell. Traitement du texte. Arborescence de fichiers. Sécurité... - #9
Development and Deployment of Multiplayer Online Games, Part ARCH. Architecture (Vol. I-III)
3 Books
What's the Big Idea? The idea behind this book is to summarize the body of knowledge that already exists on multiplayer games but is not available in one single place.And quite a fewof the issues discussed within this series (planned as three nine volumes ~300 pages each), while known in the industry, have not been published at all (except for... - #10
Growing Agile: The Complete Coach's Guide
7 Books
Growing Agile: Coach's Guide Series This bundle provides a collection of training and workshop plans for a variety of agile topics. The series is aimed at agile coaches, trainers and ScrumMasters who often find themselves needing to help teams understand agile concepts. Each book in the series provides the plans, slides, handouts and activity...