[Go] class with PHP (II)

Classes and PHP

When your create a function within a class with the same name as the class that function'll execute whenever you create a N object of that class. This is called a ' constructor. ' It allows me to have default values for the each attribute automatically whenever I create an object:

<?php $Basic = new Style;?>

Define an instance of a class by giving it a name ($Basic) and assigning it "=new ClassName;".

You could also send different values for the variables as arguments when declaring the new Style, but if you declare a Val UE You are have to declare all of them which occur to the "right of" the one you declare (class functions work-like just Functions in this respect). Meaning if you are set ' text ' to something different than the default given in Style, then your have to declare all VARIABL Es. There is a easier way. We can create a function that changes a single variable within the class:

<?php

Function Set ($varname, $value) {

$this-> $varname = $value;

}

?>

So to change the value of particular variable of a instance we can:

<?php $Basic->set (' Size ', ' 2 ')?>

Use the '-> ' operator to refer to a variable or a function of the instance. So the above tells the interpreter "Run function ' Set () ' of instance ' $Basic '." It knows that "$Basic" is a instance of class "Styles" because we declared it so. Similarly we can refer to variables of a instance in same manner (e.g. $Basic->text).

Let's create a Style for table headers that has some slightly different attributes.

<?php

$Theader = new Style;
$Theader->set (' text ', ' #0000FF ');
$Theader->set (' Bgcol ', ' #000000 ');

?>

There, that ' s good enough. Now I table header has blue text on a black background. I want my table body to being a slightly lighter gray than my main page, black are good for text, but maybe I ' ll make the text Smaller:

<?php

$Tbody =new Style;
$Tbody->set (' Bgcol ', ' #AAAAAA ');
$Tbody->set (' size ', 2);

?>