Book Image

Delphi Cookbook - Third Edition

By : Spinetti, Daniele Teti
Book Image

Delphi Cookbook - Third Edition

By: Spinetti, Daniele Teti

Overview of this book

Delphi is a cross-platform integrated development environment (IDE) that supports rapid application development on different platforms, saving you the pain of wandering amid GUI widget details or having to tackle inter-platform incompatibilities. Delphi Cookbook begins with the basics of Delphi and gets you acquainted with JSON format strings, XSLT transformations, Unicode encodings, and various types of streams. You’ll then move on to more advanced topics such as developing higher-order functions and using enumerators and run-time type information (RTTI). As you make your way through the chapters, you’ll understand Delphi RTL functions, use FireMonkey in a VCL application, and cover topics such as multithreading, using aparallel programming library and deploying Delphi on a server. You’ll take a look at the new feature of WebBroker Apache modules, join the mobile revolution with FireMonkey, and learn to build data-driven mobile user interfaces using the FireDAC database access framework. This book will also show you how to integrate your apps with Internet of Things (IoT). By the end of the book, you will have become proficient in Delphi by exploring its different aspects such as building cross-platforms and mobile applications, designing server-side programs, and integrating these programs with IoT.
Table of Contents (12 chapters)

Writing enumerable types

When the for...in loop was introduced in Delphi 2005, the concept of enumerable types was also introduced into the Delphi language.

A type is defined as enumerable if it can be iterated. That is, it can be the target of the for...in loop.

As you know, there are some built-in enumerable types; however, you can create your own enumerable types using a very simple pattern.

To make your container enumerable, implement a single method called GetEnumerator, which must return a reference to an object, interface, or record that implements the following two methods and one property (in the example, the element to enumerate is TFoo):

function GetCurrent: TFoo; 
function MoveNext: Boolean; 
property Current: TFoo read GetCurrent; 

There are a lot of samples related to standard enumerable types, so in this recipe you'll look at some not-so-common utilizations...