Page 209 - Beginning PHP 5.3

Chapter 8: Objects
Here ’ s an example that shows how to define properties then set and read their values:

< !DOCTYPE html PUBLIC “-//W3C//DTD XHTML 1.0 Strict//EN”
“http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd” >
< html xmlns=”http://www.w3.org/1999/xhtml” xml:lang=”en” lang=”en” >
< head >
< title > Defining and Using Object Properties < /title >
< link rel=”stylesheet” type=”text/css” href=”common.css” / >
< /head >
< body >
< h1 > Defining and Using Object Properties < /h1 >

< ?php

class Car {
public $color;
public $manufacturer;
}

$beetle = new Car();
$beetle- > color = “red”;
$beetle- > manufacturer = “Volkswagen”;

$mustang = new Car();
$mustang- > color = “green”;
$mustang- > manufacturer = “Ford”;

echo “ < h2 > Some properties: < /h2 > ”;
echo “ < p > The Beetle’s color is “ . $beetle- > color . “. < /p > ”;
echo “ < p > The Mustang’s manufacturer is “ . $mustang- > manufacturer . “. < /p > ”;
echo “ < h2 > The \$beetle Object: < /h2 > < pre > ”;

print_r( $beetle );
echo “ < /pre > ”;

echo “ < h2 > The \$mustang Object: < /h2 > < pre > ”;
print_r( $mustang );
echo “ < /pre > ”;

? >

< /body >
< /html >

You can see the output from this script in Figure 8 - 1 . The script defines a class, Car , with two public
properties, $color and $manufacturer . Then it creates a new Car object and assigns it to a variable
called $beetle , and sets $beetle ’ s $color and $manufacturer properties to “red” and
“Volkswagen” , respectively. Next the script creates another Car object, assigns it to $mustang , and sets
its $color property to “green” and its $manufacturer property to “Ford”.

Now that the two objects have been created and their properties set, the script displays the values of a
couple of properties: the $color property of the $beetle object ( $beetle - > color ) and the

$manufacturer property of the $mustang object ( $mustang - > manufacturer ). Finally, the script uses

print_r() to display the two objects; notice how print_r() displays an object ’ s properties in much
the same way as it displays array keys and values.

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