I've written a new demonstration in PHP ...
* a base class of line items for your accounts
* subclasses for bills and invoices you issue
* a sample application that takes a number of bill and invoice items and produces an accounts table and total
All in the ONE course file as a demo ...
here.
For a "live" application, the classes would probable be held in a separate file so that they could be shared across between a whole lot of different pages, and of course they would use a lot more attributes and be populated from files or databases
The example will work equally well in PHP5 and PHP4, even though you'll have been told that the OO model has changed between the two version!
(written 2008-06-19, updated 2008-06-20)
Associated topics are indexed as below, or enter http://melksh.am/nnnn for individual articles
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[205] PHP5 lets you say no - (2005-02-07)
[343] Should I use structured or object oriented? - (2005-06-10)
[421] Don't repeat code - use loops or functions - (2005-08-21)
[485] North, Norther and Northest - PHP 5 Objects - (2005-11-04)
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[720] Planning a hotel refurb - an example of a Gant chart in PHP - (2006-05-14)
[836] Build on what you already have with OO - (2006-08-17)
[1027] Cue the music, I'm happy. - (2007-01-09)
[1153] Object Oriented Model - a summary of changes from PHP4 to PHP5 - (2007-04-18)
[1217] What are factory and singleton classes? - (2007-06-04)
[1535] OO PHP demonstration - comparing objects and more - (2008-02-08)
[1819] Calling base class constructors - (2008-10-03)
[1820] Sorting objects in PHP - (2008-10-04)
[1925] Introduction to Object Oriented Programming - (2008-12-06)
[2160] PHP - getclass v instanceof - (2009-05-07)
[2169] When should I use OO techniques? - (2009-05-11)
[2171] Cleaning up redundant objects - (2009-05-11)
[2172] PHP4 v PHP5 - Object Model Difference - (2009-05-11)
[2380] Object Oriented programming - a practical design example - (2009-08-27)
[2434] Abstract classes, Interfaces, PHP and Java - (2009-10-03)
[2435] Serialization - storing and reloading objects - (2009-10-04)
[2632] Shipping a test harness with your class in PHP - (2010-02-12)
[2641] Object Oriented Programming in PHP - (2010-02-19)
[2680] Static class members in PHP - a documented example - (2010-03-16)
[2717] The Multiple Inheritance Conundrum, interfaces and mixins - (2010-04-11)
[2741] What is a factory? - (2010-04-26)
[2774] PHP - Object Oriented Design in use - (2010-05-21)
[2921] Does copying a variable duplicate the contents? - (2010-08-14)
[2922] Getting the OO design write - with PHP a example - (2010-08-14)
[3142] Private and Public - and things between - (2011-01-22)
[3210] Catchable fatal error in PHP ... How to catch, and alternative solutions such as JSON - (2011-03-22)
[3211] Computer Graphics in PHP - World (incoming data) to Pixel (screen) conversion - (2011-03-24)
[3607] Designing your application - using UML techniques - (2012-02-11)
[3608] Design Patterns - what are they? Why use them? - (2012-02-12)
[3609] How do classes relate to each other? Associated Classes - (2012-02-12)
[3840] Autoload in PHP - (2012-08-17)
[3841] Copying, duplicating, cloning an object in PHP - (2012-08-18)
[3843] Caching Design Patterns - (2012-08-20)
[3953] Objects in PHP - Revision - (2012-12-16)
[4057] stdClass in PHP - using an object rather than an associative array - (2013-04-02)
[4073] Learning about Object Orientation in PHP - a new set of examples - (2013-04-28)
[4356] Object factories in C++, Python, PHP and Perl - (2014-12-19)
[4366] Changing what operators do on objects - a comparison across different programming languages - (2014-12-26)
[4626] Singleton design pattern - examples and uses - (2016-01-20)
[4627] Caching results in an object for efficiency - avoiding re-calculation - (2016-01-20)
[4628] Associative objects - one object within another. - (2016-01-20)
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