<!DOCTYPE html>
<html>
<body>
<?php
abstract class ParentClass {
// Abstract method with an argument
abstract protected function prefixName($name);
}
class ChildClass extends ParentClass {
// The child class may define optional arguments that is not in the parent's abstract method
public function prefixName($name, $separator = ".", $greet = "Dear") {
if ($name == "John Doe") {
$prefix = "Mr";
} elseif ($name == "Jane Doe") {
$prefix = "Mrs";
} else {
$prefix = "";
}
return "{$greet} {$prefix}{$separator} {$name}";
}
}
$class = new ChildClass;
echo $class->prefixName("John Doe");
