Defining a class

Enough with generalisations - let's get into the specifics. Given the class structure of dogs and breeds discussed above, it's time to take a look at how that translates into PHP code. Here is the PHP code necessary to define a very basic dog class :

class dog {
    public function bark() {
        print "Woof!\n";

Here the dog class has just one function, bark(), which outputs "Woof!" - simple enough, really. Don't worry about the "public" part - that just means "can be called by anyone", and we'll be looking at that later. If we create an object of type dog we could call its bark() function to have it output the message.

Author's Note: class naming conventions follow the same rules as variable naming, excluding the dollar sign at the beginning. You can use any name for your functions, except "stdClass" and "__PHP_Incomplete_Class" - both of these are reserved by PHP.


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