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Some quick translations, OO PHP to C#

So a recent project has facilitated me brushing up on my C# – so I thought I would share some basic translations of things that can be frustrating when you know the usual programming principles (object orientated programming), but not all the syntax.

A quick couple of points to note:

  1. C# is a strictly typed language, that means you have to know about what your variables are going to be, and yes, you have to declare them somewhere sensible
  2. Accessing methods and properties within your class does not require usage of $this – you’re talking about true scope of variables and methods, so you don’t have to worry about it
  3. Public, protected and private are essentially the same
  4. You have to declare the return types on every method, none of this return an object or false stuff
  5. Namespacing is essentially the same as if you were following the PSR-4 standard
  6. Everything, including strings, are objects
  7. A single quote and a double quote are fundamentally different things

Declaring a variable

Okay, so starting with the basics, declaring a variable is basically the same, except you have to declare the type, so declaring age as a variable, integer, with the value of 25 would look like this in PHP:

$age = 25;

However, in C# it would look like this

int age = 25;

Moving into this being a property in a class, you must rather than optionally, or have to if you’re conforming to PSR-2, so in PHP it looks like this

public $age = 25;

In C# it’s going to look like this:

public int age = 25;

Declaring methods

Okay this is an easy one in PHP, it looks something like this. Using PHP 7.1 we can strictly type the return.

public function myMethod(MyClassOne &$argumentByReference, MyClassTwo $argumentByValue) : ObjectClass

{

    // Do something in your method here

}

// This would be called by doing something like
$object->myMethod($parsedByReference, $parsedByValue);

This one gets slightly different when translated into C# for a couple of reasons. You must declare the types of the parameter, the type of the response(s), it also gets a bit different when calling the method too:

public ObjectClass myMethod(ref MyClassOne argumentByReference, MyClassTwo argumentByValue)

{

    // Do something in your method here

}

// Now calling your method would look slightly different

Object.myMethod(ref parsedByReference, parsedByValue);

Using Objects

Instantiating objects isn’t much different either, really; it looks different but that’s because it’s strictly typed.

Main difference between use statements in PHP and C# (other than that it is using in C#) is that you use a namespace, the classes contained therein (this namespace only, not its children) are automatically available.

In PHP I want to include a class and then instantiate it, will look something like this:

use Vendor\Project\Namespace\ClassName;

// Then you have all of your usual declarations, which we'll get to

$myObject = new ClassName();

However when you want to do this in C# it looks something like this:

using Vendor\Project\Namespace;

// Then all of your usual declarations

ClassName myObject = new ClassName();

Declaring Classes, using Inheritance and Interfaces

This gets a bit different, but only syntactically. We’re going to create Person as an abstract class, this will be extended by the Employee class. Employee is going to implement an interface called Emailable.

For the sake of ease I’ve not separated these into different files

In PHP it would look like this:

abstract class Person{

    // Shared functionality here

}
interface Emailable{

    // Interface requirements here

}

class Employee extends Person implements Emailable{

    // Employee functionality, including Emailable requirements, in here

}

In C# however it would look like this

namespace ObjectOrientatedPrinciples.MyExample
 {
    abstract public class Person
    {
        
    }
    interface Emailable
    {
        
    }
    public class Employee : Person, Emailable
    {
        
    }
 }

You will see from this that C# doesn’t necessarily draw the distinction between classes being extended and interfaces being implemented.

Arrays and Lists

This is actually the only thing I found to be a little bit painful, however there is a decent tutorial on arrays on the Microsoft Developer Network (MSDN)

Closing Off

I’ll leave it at that for tonight. But a quick few bits that I thought might help someone out, it would’ve helped me if I could’ve found this article this morning. Though admittedly probably only saved me an hour or so. Not the point though, here it is 🙂

How to build a terrible API

Hi everyone

As you may know, throughout my career I’ve ended up doing a lot of integration development. Middleware, APIs, all that kind of stuff. So I thought I would write a quick list of the things you should definitely do to make your API really terrible for other developers to use, so that they put their heads through their desks trying to integrate with it.

Judging from some of the APIs I’ve had the misfortune of integrating with, I thought this was worth writing, for anyone who is building an API.

Obviously this post is humorous or satirical, if you like. Please, for the love of all that is good and sacred in this world, don’t follow these tips!

Tip #1 – Don’t write a darn thing down

No developer likes reading documentation, let alone writing it. So the best tip to make sure that everyone hates your API is to make sure you don’t write a single thing down. Not a thing, nada. Let them guess at how to use it and marvel at your ivory towered genius.

Tip #2 – Make sure that your API is totally inconsistent, especially with documentation

So if you did go to the effort of cobbling together some documentation, and this is critically important, you absolutely must ensure that it is totally out of date. It should be at least 2 major versions behind your developments to keep your job safe.

Also, make sure there are plenty of typos in field names, don’t spell check anything at all; and be sure to use plenty of three letter acronyms that only people within your organisation understand. This will make integration even more surprising.

Top tips for inconsistency include ensuring that you use an absolute minimum of three naming conventions, and at least four different response structures.

Tip #3 – Make sure you use all the wrong terminology

If your API is a straight-up JSON-POST API, which is really simple to use, make sure you throw in a few curve balls. Maybe some GET requests in there, maybe even the occasional PUT or PATCH. It just keeps things entertaining. Parse the API key in the header in some requests, a query string in others and part of the initial request object in the rest.

Also, make sure your account/client/public facing departments refer to your RESTful APIs as Fairy Liquid, and your SOAP APIs as Sleepy ones. This will make sure everyone finds your technical capacity fantastic and will marvel at your technological prowess.

Tip #4 – No version control

If you don’t make sure that your API is versioned, it will keep the developers integrating with it in work; because every time you change it they will have to rapidly drop all of their mission-critical developments to fix any integrations. Be sure to release a patch, break some calls, and then roll it back. Just to punish anybody not using version control on their integrations.

Don’t do anything silly like adding version control, or advanced warning of changes, and definitely don’t even think about doing Beta releases. That just takes the fun out of integration development.

Tip #5 – Throw as many random errors as possible

What you definitely shouldn’t do, under any circumstances, is have a unified and consistent way of handling errors, such as a resource not found or an API key not matching. These errors must be handled differently for every single possible error, on every single possible call.

This is really good for the economy, because it ensures that any developers integrating with your API will have to test every single possibility, against every single call you have. This will keep them in work. You’re doing them a favour, honest.

Why give a JSON error response back, detailing an error code and a human readable message, when a 404 or a 500 will do, that’s what they’re there for! Bonus points if you can throw a 301.

And you’re done.

If you follow these 5 simple rules, you will have a super-awesome-epic API built our of pure ivory, which people will have to pay you to integrate with, because nobody else will know how to.

Then you’ll become like Zuckerberg-cum-Gates rich and be proper leet hacker wizard man (or witch woman).

So there you have it. From someone who’s built, and integrated with, several (probably dozens of) APIs. The top list of things you should definitely never, ever, ever do, if you don’t want to burn in hell for the rest of eternity, stuck in an infinite loop of torture, ridicule and unknown fatal exceptions.

Peace out y’all! 🙂

I’d genuinely love to hear any additional tips you’ve got to build brilliant APIs, and your hilarious anecdotes which are only funny now because you’ve finished the course of therapy and sedatives and recovered from your caffeine addiction enough to laugh at them!

Tech Team Cancer

Hi guys

I keep promising that I will be posting frequently, and then life happens. I will continue my posts and tutorials and trying to share and disseminate things I’m learning or have learned over the course of my career.

I’m incredibly lucky, not only do I have my own experiences and exposures to draw upon when trying to make decisions, but I have a number of friends in development, from starting their careers right through to development managers and such. Of course, it would be unfair for me to take all of the credit for the things I’ve learned along the way, and at some point in the near future I might post a list of people I’ve learned from, but it will be a long list; and it would be wholly unfair for me to miss anybody crucial out of that list. It’s been a long career so far and I’ve met a lot of people.

Anyway, today I want to cover a topic that’s quite close to my heart. I received a huge compliment the other day from a long time friend of mine, Oliver Sarfas, he was saying that he has just picked up a piece of software I’d developed. Now I want to throw some context into this, I first met Oliver when I was only a couple of years into my career. We have stayed in touch the whole time, but were professionally reunited at my last role.

This particular piece of software, it’s fair to say, is quite complicated in its structure; in that very little is hardcoded anywhere. I was taking a matrix of equations and building them into a data structure, running them against years of legacy data as a rule by which to calculate some financial information. In terms of fluidity and flexibility it’s one of the most complicated bits of software I’ve built. It had a feature or two that I didn’t get to finish before leaving for my current role.

Anyway, Oliver was tasked with finishing up the project by building some of the functionality I didn’t get chance to do. He sent me an email, the long and short of this email was a thank you for writing code using industry standard techniques and leaving decent documentation. I can only presume following PSR-2, known design patterns, and decent naming conventions played some part of this.

This really conveniently brings me to the point of this post:

Tech Team Cancer

It sounds like a really horrible thing to refer to, but truthfully the things I am about to describe are cancerous. I’m not pointing at any of my previous roles here, everyone does at least one of the things on the list, some companies are better than others, but generally, these things help kill tech teams:

1. Not Leaving Documentation (Ivory Towering)

There is nothing worse than finding yourself having to work on a project you know nothing about, that has no code comments or documentation attached.

One thing I would like to say on this, however, is code comments are great tips for a developer. But code comments document that piece of code, that module, that class. They don’t document the over-arching design or principles of the piece of software.

Documentation is essential in other developer’s being able to work on your software.

2. Not Following Patterns

This is a bit of a weird one. Using known design patterns, and principles, and everything else does help your code’s maintainability. But what I really mean here is being consistent, across all of your code (really it should be across all of your team’s projects). Any convention is better than no convention.

If you have a piece of software and you name all of your classes following PSR-2 standards and your namespaces follow PSR-4, great! Get everything else consistent too, table and field names are a really common one for this.

3. Not Knowing When You’re Out Of Your Depth

This is another seriously fluid one. Any time you are out of your depth is bad. It doesn’t matter the context. Don’t fully understand the specification, don’t fully understand what they’re aiming to gain, or the use case, for this software, don’t understand the technologies you’re using. Any of these things lead you to build bad software.

What usually happens, in my experience, is that you, for want of a better phrase, blag it. Blagging, in development, is terrible. It means you don’t have a plan, if you don’t have a plan how can you have a coherent software design and accompanying principles?

If you have none of those things you’re destined to end up with spaghetti code, indecipherable nonsense and, as you learn more about what you’re supposed to be doing, horrendous shoe-horning to make functionality work.

The big problem with this one is that if you fall foul of it you will definitely fall foul of the other points here as well.

4. Bad Commit Messages

We’ve all been in that position where we’re asked to fix a bug on an existing piece of software. Fair enough. And then we look at the code, and all we can say or think (depending on your personality) is “Oh for ****s sake, what the **** was that **** thinking?! Seriously why the **** would you do that?” and this usually lasts for a few hours, before resigning yourself to shoe-horning in the resolution or stating it has to be rebuilt.

This is where a decent commit message goes a long way, and a code comment. If I have to do something a bit nasty, dirty or something that would get my immortal soul cussed out once I’ve left the office, I leave a code comment and a commit message; keeping professional but saying something like “This is a workaround for requirement X which was introduced after the original specification; if you change it Y will happen and you will also need to check Z” – because that’s the kind of information I would like to find if I were inheriting the maintenance of that code.

A good commit message is the difference between “Why the hell did you every hire X? He didn’t know what he was doing!” to “Ah, right. I see why he did that, it sucks, but I get it”.

5. Relying on Tribal Knowledge

This one is so much more dangerous than it sounds. When you build something, or when you fix an issue. This one isn’t just for developers either, testers, client facing staff and project staff are all guilty of this (usually). If you know something about a project or a piece of infrastructure it really does need to be written somewhere.

Take this real world example. I was working on a large and complex project which was business critical for the company that I was working for at the time. We were nearing the end. Luckily I keep documentation and code comments pretty up to date and always communicate how I’m working on. Unfortunately one Friday afternoon, I’m on my way home from work, all is good, we’re ahead of schedule and everything is great with regards to the project.

Then I’m on my way home, hit oil and come off of my motorbike. I go rolling up the A14 in Cambridgeshire, breaking and dislocating my shoulder and snapping my thumb. That’s me unable to drive for about 12 weeks in total. I was really lucky, firstly I didn’t die. Secondly, I used to work part remotely, so was able, within a couple of days and a makeshift injury-friendly work space, to get working again.

Imagine if it were worse, or if I couldn’t have worked remotely. The company I was working for would’ve been right up the creek without a paddle.

In Summary

To summarise this article. The main problems any development team, whether growing or shrinking, young or old, is information and sharing it.

Whether you’re sharing it through documentation, code comments and git commit messages. Or however you’re sharing it. Whether than information is software design, client facing, client requirement, anything at all. If ever there is a piece of information that you, and you alone, have you need to find a way to share it; otherwise you really are asking for something to go wrong with no conceivable disaster recovery available.

Tips for commercial WordPress, and open source, development

Hi everyone

So I’ve been using content management systems on and off for the best part of 10 years. From the by-gone days of PHP Nuke and when content management systems like PHP Fusion were all the rage. To using more modern, and definitely more widely adopted systems like Joomla and, of course, WordPress; and just to throw other open source stuff into the mix, platforms like Moodle.

Now I’ve returned to using WordPress on a daily basis, but from a different perspective; I don’t do too much development on WordPress personally; my skill set generally lies in building things on frameworks such as CodeIgniter and Laravel, if not bespoke. But I do use WordPress to the extent of managing multisite installations, managing production stability and servers, as well as deployments and migrations.

Having been in the unique position to pick up some legacy code in my time, and seen what does and does not make a WordPress site easy to work on, manage and maintain; I thought I would put together some tips for building WordPress sites, and functionality, which will stand the test of time.

1. Never modify the core

This is a deadly serious one. No matter what you’re working on it should have a specific way of extending functionality, whether through plugins and themes, extensions or a specific namespace where modifications should be added, never, ever, ever modify the core. The same applies to the core code on a plugin.

The reasons for this are really simple; you probably don’t know and understand the full architecture or what you might break by changing this, and more importantly the biggest strength of using something open source is that updates are generally frequently available. The moment you change something in the core you’re going to sabotage any upgrades; you will have to make the choice. Either update the software (absolutely critical) and lose your changes, or don’t update the software and risk leaving bugs, security vulnerabilities, and all kinds of other stuff in there. Not a good position to be in.

2. Choose the right one

WordPress is the most widely adopted content management system in the world. Impressive, right? And technically, yes, anything can be built on it. In the same way any system can be built using .txt files for data storage. It can be done, but that doesn’t mean it should be.

I’ve laboured this point a few times in a few articles and things, but a good developer will know the tools available to them and choose the best one for the job. It is worth spending six months for a content management system and blogging platform, that does exactly the same as WordPress? Of course not. Is it a good idea to build a secure intranet containing sensitive data about national security on WordPress? Of course not. It’s about knowing what’s available and making the best decision based on this.

This is a difficult one, however, as you need to choose the one that fits your needs right now, as well as being compatible with the long term visions of the site; or know from the start that a rebuild will be necessary.

3. Be wary of plugin dependencies

Why use plugin_function when cms_function does the same job, and is probably going to be better supported in the future? When installing plugins, extensions and add ons; always think about the eventualities? What if this plugin’s core is compromised and I need to disable it right now; what will break? What if the plugin stops being supported? How tied into using it am I right now? If you’re managing lots of websites, especially; be wary of the headache you’re going to have if you’re relying too heavily on too many plugins.

If you notice yourself using plugin X on every site you build, or relying on it super heavily, it might be worth doing one of a few things. Either building your own replacement, so you’re in control of the core. Or perhaps wrapping it in your own functionality, so if you want to swap it out, you can. Using a technique called Facading can help with this, hiding plugin functionality behind you facade means you can swap what’s behind the facade out if you need to.

Really the point here is don’t install things willy nilly, think about the dependency you’re creating on this plugin for your website, and how much of a pain it’s going to be if you want to remove it.

4. Always check the source

Depending on the project and the size reading the source code line for line probably isn’t going to be efficient; so that’s not what I’m suggesting here. By source I mean the author, the factory, the company; wherever it comes from. Make sure they’re trusted, WordPress, for example, examines all of the plugins and themes submitted to their public repositories and they’re pretty stringent on their standards, as well as ensuring they’re safe (from a security standpoint).

Most mainstream CMS have white hat security scanning tools that will uncover most, if not all, known security flaws and vulnerabilities. Running these can only be a good thing, as long as you act on the results you get.

5. Don’t be afraid to code things from scratch

There might not be a plugin which does what you want, or doesn’t do exactly what you want. You have 10 requirements from your client. Plugin X fulfils 9 of them. Do not try and hack it to fulfil the 10th, it will only go badly; honestly, I’ve been there and done it a bunch of times.

Just because you usually use X plugin and Y CMS, doesn’t mean you have to this time. Some things are best built from scratch, whether the whole site/software, or a specific functionality. Sometimes the best option is to get stuck in with coding the thing you want. You’d be surprised at how quick this can sometimes be. And just because your CMS offers a specific functionality doesn’t mean you have to use it. WordPress Custom Post Types are a beautiful example of this, as well as their taxonomies. These are both beautiful pieces of functionality; but they’re not the best way to store bespoke data, for example. They exist for a range of things, but primarily to give you a way to show bespoke content, like recipes, and linking them together in a specific way, dietary requirement for example. Storing anything that doesn’t fit into a custom post type and taxonomy doesn’t make sense, so don’t do it.

From procedural to object orientated, a tutorial

Hi there everyone

Something I’m often faced with, having lots of friends with varying degrees of programming experience, is how do (PHP) developers move from sub 25k roles to the higher end of the spectrum, the 35-60k developer roles.

Generally, in my experience, the are some key differences in the salary expectations and the skills you can expect for a developer demanding those salaries. These can be broadly summed up as below:

  • True understanding of object orientated programming
  • Knowledge and application of programming principles
  • Exposure to multiple technologies and ability to move around within them
  • Web application development vs website development (the difference between relying on browsers and being able to do things like offloading, queueing, sharding, true separation of concerns, performance optimisation, caching, all that stuff)

To this end I’ve had a decent number of developers ask me how to start working with classes, and work in an object oriented way. So I thought I would do a tutorial on this. I’m going to cover some design patterns, some PHP functionality and various other things.

This is going to be a long and wordy tutorial, but hopefully what it will do is give you some understanding in the differences between procedural and OO programming.

All code samples are available in this project on my GitHub

Step One: The Hardest Part

The first thing I am going to disclaim is simple: Please do not try to have a half procedural, half OOP project or system. It’s going to be an absolute nightmare to maintain!

Now that’s out of the way, let’s talk about some design basics. Avoid god classes! A god class is a class which has many, many responsibilities, it can do everything. In terms of a practical application of a God class think of an ecommerce system: if a single class is responsible for checking stock, adding items to your basket, emptying your basket, and the checkout process – it has far too much responsibility.

I always think it’s a good idea to follow the Single Responsibility Principle – to those new to this I simple explain it as follows:

A class should be responsible for a single job. If you can’t tell me, in a sentence, what it does; then it is almost definitely doing too much.

As such if you have a requirement for an ecommerce system as defined above, checking stock levels would be it’s own class. The point of this is so that:

  1. The class can be used throughout your project, anywhere that you need to check stock levels
  2. The class can be modified and know that all stock checking functionality happens through a single place
  3. Any business logic can be contained in a single place
  4. The class could be swapped out if needs be, again you know all functionality is encapsulated here

Encapsulation: Goes hand in hand with “DRY” (don’t repeat yourself). Basically bringing everything to do with a certain concern (i.e. stock checking) into a single place, rather than leaving it scattered throughout your code.

So you now have a basic idea of what you use a class for, and in what scenarios you would create a new class – basically, any time you need to get something done.

Now working with objects, as opposed to working with a bunch of variables, has some real perks.

NB: Throughout this article I am going to refer to “classes” and “objects”. For all intents and purposes a class is defined, an object is instantiated. Therefore my User class, once it physically exists, becomes an object, until that point it is a class.

If I have an “Order” object rather than a whole heap of variables or a massive multi-dimensional array, I can put functionality in there which I need, I can do decisions and logic based on information contained within that order. What you’re doing is neatly organising everything into it’s own compartments within your code.

The user may be hitting a button to “add to cart”, but in practice you might be doing all kinds of things; checking the stock level, applying voucher codes, modifying the stock level, calculating the value of the cart so far, all sorts. So this separation becomes invaluable.

However, the point of this part of the article is simple. It’s going to be really difficult to follow, and make almost no sense, to have a bunch of objects floating around a procedural execution. The reason for this is, again, simple; if you have some stuff procedural, and some wrapped in classes and objects; how the heck could I possibly know where to look?

Learning Point Two: Using and understanding the syntax

In this point we’re going to cover some basic concepts:

  1. Inheritance – abstracting and extending classes
  2. Interfaces – implementation and usages
  3. Properties, Methods, Privacy and Scope

Firstly, one of the beautiful things about classes is inheritance. Let’s take a basic example of a User. A User might be a Guest, a Member, a Moderator and an Administrator; but they almost definitely share a bunch of common functionalities, like having a user ID for example (though a guest’s would be 0 or null). You don’t want to have to write a whole heap of code to get the user ID a bunch of times, when it’s the same functionality. You want all of your different types of users to share this functionality, this is where inheritance comes in.

Inheritance

<?php

abstract class User
{
    protected $userId = 0;
    protected $isLoggedIn = true;
    protected $isStaff = false;
    public function getUserId()
    {
        return $this->userId;
    }
    public function isLoggedIn()
    {
        return $this->isLoggedIn;
    }
}

class Guest extends User
{
    protected $isLoggedIn = false;
}

class Member extends User{}

class Moderator extends Member
{
    protected $isStaff = true;
    public function hasPermission($permission)
    {
        // Some logic here and return TRUE or FALSE
    }
}

class Administrator extends Moderator
{
    public function hasPermission($permission)
    {
        return true; // Administrators can do anything
    }
}

See in GitHub

The handy thing about this is that everyone is a User. So if ever I try to manage some dependency and state that a User is required as an object, I can do this really easily, because everything extends off of User, or one of its derivatives.

Also everyone from Guest to Administrator has a getUserId method, which is quite handy and an isLoggedIn method, so it doesn’t matter if my factory returns me a Guest or an Administrator, the functionality is going to work.

Just to clarify some bits here. Guest::isLoggedIn is false, but Member::isLoggedIn (and everyone who extends Member, or Moderator) returns true. Moderator::isStaff returns true as does Administrator::isStaff (because of the inheritance).

Site note: You could never do: $user = new User(); Because User is defined as an abstract class, as such you could do $administrator = new Administrator(); (or any of the other classes)

Interfaces

An interface is, the best way I’ve heard it described, is the difference between plugging a socket into the wall, vs having to wire in your lamp by hand. You can define an interface on an object, to ensure it conforms to certain standards, basic example now of an Emailable interface.

This interface ensures that the entity, whatever it is (User, Customer, Employee, Organisation, Website) can be emailed, by specifying it must have some methods available to it.

In this example we can make anything we want emailable, by simply adding the methods defined and stating that this class implements the interface – now we can send an email to the fridge if we wish, as long as it can define those methods!

<?php

interface Emailable
{
    public function getRecipientName();
    public function getEmailAddress();
    public function acceptsHtmlEmail();
}

class Client implements Emailable
{
    public function getRecipientName()
    {
        return 'Very Important Company Plc';
    }
    public function getEmailAddress()
    {
        return 'someone.somewhere@clientwebsite.com';
    }
    public function acceptsHtmlEmail()
    {
        return true;
    }
}

class Employee implements Emailable
{
    public function getRecipientName()
    {
        return 'John Doe';
    }
    public function getEmailAddress()
    {
        return 'john.doe@ourcorporateemail.com';
    }
    public function acceptsHtmlEmail()
    {
        return false;
    }
}

Sample on GitHub

Implementing an interface: Simply means that we have defined an interface, and the class which implements that interface conforms to it. Then if we define Emailable as a type hint, PHP will force not only that the class implementing the interface, but also that any object parsed into an Emailable type hinted parameter conforms. Otherwise it’ll throw a hissy fit and not work

Scope!

The big one that catches a lot of new-to-OOP developers out is variable and method scope. So here is a quick and simple one:

  1. Public – these methods and properties can be accessed (as long as the object is instantiated) from anywhere that has access to the object
  2. Protected – these methods and properties can be accessed within this object (or derivatives)
  3. Private – These can only be accessed specifically within this class
  4. Static – These can be accessed from the class itself, without needing the instantiation of an object
  5. Constants – As in PHP itself, these never change

That’s the long and short of it. Word of warning! Always assume your code is going to be copied, recreated and used throughout a system and if it is open source by anyone anywhere in any way they feel like it. So be very careful what you expose as public, once it’s public you have to assume code is relying on it, and as such ensure you are backward compatible – what I’m saying is it is easier to change $myProperty and myMethod to be public later, if they were protected before, than to change them from public to protected – because who knows what you might break!

Accessing properties can be done as follows:

Please do not try to run this code, it won’t work 🙂

<?php

class Scope
{

    // I will never change
    const GITHUBURL = 'https://github.com/johnothecoder';

    // I can be called from the class, without instantiation, and can be shared across multiple instances
    public static $fullName = 'Matt Johnson';

    // I can be access from anywhere the object exists
    public $alias = 'JohnoTheCoder';

    // I can only be accessed from within Scope or a class which extends Scope
    protected $name = 'Matt Johnson';

    // I can be called from anywhere
    public function getAlias()
    {
        return $this->alias;
    }

    // I can be only be called within Scope (or classes which extend scope)
    protected function getName()
    {
        return $this->name;
    }

}

// Executing some code

echo Scope::GITHUBURL;
echo Scope::$fullName;

$scope = new Scope();
echo $scope->alias;
echo $scope->getAlias();

// But I can't do this
echo $scope->name;
// Or this
echo $scope->getName();

As always, sample available on GitHub

I can’t really talk you through the full spec of this one, as there’s not much to talk through, really it’s just a way of showing you what can and can’t be done within the scopes of an object.


Hopefully this article has been of some use to those of you looking to get into the big wide world of object orientated programming with PHP. Next time I will be covering how to use Dependency Injection, the Factory and Service locator pattern and polymorphism to your advantage 🙂

Thanks for reading!