Tutorial: Creating a Database Application using Delphi

This tutorial guides you through the creation of an InterBase database application with which you can view and update a sample employee database. You will use the Delphi IDE to create the database application. 

Table of contents

• Creating a database application using the Delphi IDE
• Overview of database architecture
• Creating a new project
• Setting up data access components
• Setting up the database connection
• Setting up the unidirectional dataset
• Setting up the provider, client dataset,and data source
• Designing the user interface
• Creating the grid and navigation bar
• Adding support for a menu
• Adding a menu
• Adding a button
• Displaying a title and an image
• Writing an event handler
• Writing the Update Now! command event handler
• Writing the Exit command event handler
• Writing the FormClose event handler

Programming elements with Delphi

Project concept

Delphi allows you to create one application at a time, open as a project A project is the uncompiled state of an application A Windows application consists of windows. The Delphi project that generates the application contains these windows: the cards Each card has a single unit (Pascal code that describes the contents of the card (buttons, menus, check boxes, ...) and its operation. (what happens when you click a button) and many other things): it is possible to use units that are not associated with any form

Project files

A Delphi project consists of a project file, units, and forms. The project file has the extension .DPR
Each form is stored in a file with the extension .DFM
Each unit is also stored in a file with the extension .PAS
The form and its associated unit have the same file name (Delphi only asks for this name once and uses it for the unit and for the form): if the form is stored in a Somme.DFM file, its associated unit will be stored in the Somme.PAS file

Compilation of a project

During compilation, each form (.DFM file) with its unit (.PAS file) will be transformed into a single file (.DCU)
All .DCU files will be transformed into a single .EXE executable file that represents the generated Delphi application. : The .EXE file has the same name as the .DE project file