#! code

If you create classes in PHP then you should be unit testing them as much as you can. Setting up unit testing classes for your code can be time consuming and involve a bunch of copying and pasting. Thankfully, PHPUnit comes with a couple of helper functions that allow the creation of unit testing classes automatically, which can save a bit of copying and pasting.

Question

What is the difference between these two lines of code and can you produce the background code used for them?

// Line 1
$MyClass->MyMethod();

// Line 2
MyClass::MyMethod();

The instanceof operator is used in PHP to find out if an object is an instantiated instance of a class. It's quite easy to use and works in the same sort of way as other operators. This can be useful to controlling objects in large applications as you can make sure that a parameter is a particular instance of an object before using it. Lets create a couple of classes as examples.

When validating a password it is easy enough to make sure that the password is of a certain length, but what happens if you want to make sure that the password has at least one number, or contains a mixture of upper and lowercase letters? I recently had to validate a password like this and so I created a password validation class that allows easy validation of a password string to a set of given parameters, but also allow these parameters to be changed when needed.

When Google looks at a page it takes a snapshot of that page and uses this to match against the query a user entered. To view these cached pages run a Google search and look at the Cached link next to the green URL text of the result. When you view the cached page Google will also give you a date that the page was last cached on. This can be used as a metric of your sites importance as the more often the site is cached, the more favourable Google views your page.

The is.gd URL shortening service is yet another site that converts a long URL into a small one, but is.gd differs in that it generally produces smaller URLs than others. The is.gd API doesn't require that you create an account on the site, but there are one or two limitations to using the service that you should be aware of first. You can find out these limitations by reading the is.gd terms and conditions.