Delphi
Delphi
Delphi is a programming language used to rapidly develop software applications on various platforms, including Windows and macOS. It is an object-oriented language and was originally released in 1995 by Borland as part of the Borland C++ product. It is now owned by Embarcadero Technologies.
Delphi is a powerful, object-oriented programming language developed and marketed by Embarcadero Technologies. It is based on the Pascal language and is an alternative to Microsoft’s Visual Basic. Delphi was originally created by Borland in 1995 and was later acquired by Embarcadero in 2008. The language enables developers to rapidly develop Windows and macOS applications with graphical user interfaces (GUI) and database access. Delphi is a popular choice for RAD (Rapid Application Development) programming due to its fast and powerful development environment.
History of Delphi
Delphi was originally released in 1995 as an Pascal-based object-oriented language. Borland’s team of engineers, led by Anders Hejlsberg, designed the language to be a simple development environment for Windows applications. Over the years, Borland released several versions of Delphi that included new features, such as database access, enhanced GUI tools and multithreading support. In 2008, the rights to Delphi were acquired by Embarcadero Technologies. Embarcadero has since released numerous versions of Delphi that contain new features, such as improved IDE, better debugging tools and support for mobile devices. Delphi is still actively developed and supported by Embarcadero and is a popular choice for Windows and macOS development. Delphi was initially developed as a Pascal-based language customized for the needs of the Rapid Application Development (RAD) environment built into the Borland IDE. It was designed to be a “first-class” Windows development tool, incorporating graphical user interface (GUI) components and the ability to access existing Windows libraries. In 1997, Borland released Delphi 4, which included the first true object-oriented features, transforming Delphi from a procedural language to an object-oriented one. Delphi 5, released in 1999, further improved the object-oriented features of Delphi, and added support for web development using ActiveX and COM components.
Delphi is a programming language based on the Pascal programming language. It was developed by Borland in 1995 and is often used by programmers to create Windows-based applications. The language is object-oriented and has support for classes, objects, and structures. It has built-in support for database access and multimedia elements, as well as a range of tools and libraries that aid in the development process.
Origins
Delphi was created by the Borland Corporation in 1995 as an alternative to C++. Originally called Object Pascal, the language was designed to be easy to learn and use for both novice and experienced developers. The syntax is similar to Pascal and is designed to be compatible with the Pascal compiler.
The language was originally intended to be used to develop database applications, but since its creation it has been used for developing a wide range of applications, such as: medical and financial software, videogames, web browsers, and other types of applications.
Overview of Delphi
Delphi is a programming language and software development environment used by developers to create a wide range of applications. It is an object-oriented language that lies on the border between compiled and interpreted languages, providing rapid application development with a very fast compiler and native compilation for the Windows platform. Many language elements are shared with Pascal, C and C++, making it easier for those familiar with these languages to learn Delphi.
Delphi was initially released in 1995 as part of Borland’s suite of RAD tools. It was one of the first development environments to encompass a complete visual interface for Form design, menu and toolbar design, and data access.
With its core strengths in Windows development (database, graphics, and networking technologies), Delphi has been widely used to create business applications. It is also popular among students, hobbyists and professional programmers alike.
Features
Delphi has many features that make it a suitable language for rapid application development. It has a clean syntax that is easy to learn, and its Object Pascal language is based on Pascal and is fully compatible with the Pascal compiler. It also has powerful debugging tools and refactoring capabilities.
In addition, Delphi has integrated database support and uses an open source database engine called Firebird. This allows developers to quickly build database-driven applications. Additionally, Delphi has a modern user interface library with support for various components, including buttons, menus, and grids.
Delphi also supports the development of distributed applications using the Remote Data Objects (RDO) protocol. RDO is a protocol layer between databases and remote clients, allowing clients to access data from any database without having to write their own code or know SQL statements.
Delphi provides a variety of features meant to simplify application development.
Visual Component Library
The Visual Component Library (VCL) contains many components and objects that can be quickly and easily added to a project. These components provide drag-and-drop functionality that speeds up development and decreases potential errors.
Database Support
Delphi includes a library of database-aware components that allow developers to quickly create database applications. This includes support for popular databases like Oracle, Microsoft SQL Server, InterBase, and Firebird.
Object-Oriented Programming
Delphi is an object-oriented programming language that supports inheritance, encapsulation, polymorphism, and other principles of OOP. This makes it easier for inexperienced developers to start creating applications, and for experienced ones to get the most out of the language.
Fast Compiler
The Delphi compiler is extremely fast, allowing for quick feedback and iteration during development. This helps significantly reduce time to market for applications.
Native Compilation
With Delphi, developers can compile their code into native executables for many platforms, including Windows and macOS. This allows developers to create applications that run quickly and efficiently on the target platform.
IDE
Delphi includes a fully-featured integrated development environment that simplifies the entire development process. The IDE comes with a code editor, debugger, and integrated help system, making development faster and easier.
Examples of Delphi Usage
Delphi has been used to create a variety of applications, ranging from simple games to sophisticated business systems.
Games
Delphi has been used to create some of the most popular PC games of all time. One example is Age of Empires III, a real-time strategy game created by Ensemble Studios. The game was released in 2005 and became an instant classic, winning numerous awards and selling millions of copies worldwide.
Business Applications
Delphi is also popular for creating business applications. Many companies have used the language to develop custom software for their businesses, ranging from invoicing systems to complex ERP solutions. For example, Korean company Korea Construction Company uses Delphi to develop their own business software.
Web Applications
Delphi can also be used to create web applications. Developers can use the language to create powerful web applications that run on Windows servers. One example is the popular content management system Sitecore, which was built using Delphi.
Code Example
The following code demonstrates a basic “Hello World” program written in Delphi:
program HelloWorld;
begin
Writeln('Hello World!');
end.
When compiled and run, this code will output the message “Hello World!” to the console.
Delphi is widely used in the development of business and financial software. Many major companies have adopted Delphi for developing their accounting systems, billing systems, and other related applications. It is also used in the development of medical software, such as electronic medical records, imaging systems, and patient tracking applications.
Due to its powerful debugging and refactoring capabilities, Delphi is increasingly being used in the development of game engines and video games. It is also popular among web developers, who use it to create dynamic websites and web applications.
Below is an example of a simple Delphi program that prints “Hello, World!” to the console window.
program HelloWorld;
begin
WriteLn('Hello, World!');
end.
The following example shows how to create a class in Delphi and use it in a program.
type
TPerson = class
name : string;
age : Integer;
end;
var
person : TPerson;
begin
person := TPerson.Create;
person.name := 'John Smith';
person.age := 42;
WriteLn('Name: ', person.name);
WriteLn('Age: ', person.age);
end.
The following example shows how to connect to a Firebird database in Delphi.
uses
DBXFirebird, DB;
var
Conn : TDBXConnection;
begin
Conn := TDBXConnectionFactory.GetConnectionFactory.GetConnection;
try
Conn.Open;
finally
Conn.Free;
end;
end;
The following is a simple code example of a Delphi program that prints “Hello World” to the console window:
program HelloWorld;
begin
writeln('Hello World!');
end.
This example shows how easy it is to write a simple Delphi program. The program keyword starts the program,
the begin keyword indicates the start of the main code block and the end keyword indicates the end of the code
block. In between, the writeln command is used to print the string “Hello World”.
Building Desktop Applications
One of the most common uses of Delphi is to build desktop applications. These typically involve the creation of GUI windows and forms, and the use of components such as buttons, list boxes, table grids, etc.
A simple example of this is a contact list application. The user might enter their contacts’ details into the application, and then view or edit them at any time. The program could have a main window with a list of contacts, and individual windows for entering and editing contact details.
The following simple Delphi code snippet creates a form with a button that shows a message when clicked:
// Creates a form
var Form1 : TForm;
// Creates a button
var Button1 : TButton;
// Initializes the form and button
procedure InitializeForm;
begin
// Create an instance of the form
Form1 := TForm.Create(nil);
// Set the caption for the form
Form1.Caption := 'My Form';
// Create an instance of the button
Button1 := TButton.Create(Form1);
// Set the caption for the button
Button1.Caption := 'Click Me!';
// Set the size and position of the button
Button1.Left := 10;
Button1.Top := 10;
Button1.Width := 100;
Button1.Height := 25;
// Register the OnClick event for the button
Button1.OnClick := @Button1Click;
// Add the button to the form
Form1.InsertControl(Button1);
end;
// Button click event handler
procedure Button1Click(Sender : TObject);
begin
ShowMessage('Hello World!');
end;
begin
InitializeForm;
Form1.ShowModal;
end;
Creating Web Applications
Delphi can be used to create web applications that run on web servers, such as Apache or IIS. Delphi applications can also run on ASP.NET or Apache/Tomcat-based servers.
The following example code creates a web service using Delphi:
uses
Data.DBXJSON,
Datasnap.DSProviderDataModuleAdapter,
Datasnap.DSAuth,
Web.WebReq;
type
TService = class(TObject)
private
{ Private declarations }
public
function EchoString(Value: string): string;
end;
function TService.EchoString(Value: string): string;
begin
Result := Value;
end;
var
WebModuleClass: TComponentClass = TService;
exports
ServiceGetModule,
DSHTTPWebDispatcherInvoker;
initialization
WebRequestHandler.WebModuleClass := WebModuleClass;
Advantages of Delphi
-
Easy to learn: Delphi is based on Pascal, which is a relatively easy language to learn. Even novice programmers can quickly understand the syntax and start programming.
-
Faster development: Delphi’s rapid application development (RAD) features allow developers to create applications faster than other languages. This makes it an excellent choice for rapid prototyping and rapid deployment.
-
Cross-platform support: Delphi can be used to create applications on Windows, macOS, iOS and Android platforms. This makes it a great choice for multi-platform development.
-
Extensive library: Delphi comes with a large library of components, such as buttons, grids, panels, text boxes and more. These can be easily incorporated into applications to quickly add functionality.
Conclusion
Delphi is a powerful, object-oriented programming language that enables developers to rapidly develop Windows and macOS applications with graphical user interfaces and database access. The language is based on Pascal and is easy to learn, making it a popular choice for RAD programming. Delphi offers many advantages, including faster development, cross-platform support and a large library of components. It is used in a variety of applications, such as web applications, desktop applications and mobile applications. With its powerful features and easy-to-use development environment, Delphi is an excellent choice for developing applications.