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<?php // Abstract base class abstract class Car { public $name; public function __construct($name) { $this->name = $name;
 }
 abstract public function intro(); 
}
// Child classes
class Audi extends Car {
 public function intro() {
 return "German quality! I'm an $this->name!"; 
 }
}
class Citroen extends Car {
 public function intro() {
 return "French extravagance! I'm a $this->name!"; 
 }
}
// Create objects from the child classes
$audi = new audi("Audi");
echo $audi->intro();
echo "<br>";
$citroen = new citroen("Citroen");
echo $citroen->intro();
?>
 
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<p><a href="http://altstyle.alfasado.net">AltStyle</a> によって変換されたページ <a href="https://www.w3schools.com/php/phptryit.asp?filename=tryphp_abstract">(->オリジナル)</a>
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German quality! I'm an Audi!
French extravagance! I'm a Citroen!