class Glass
{
}
class redGlass extends Glass
{
public function display()
{
echo "发射红光<br/>";
}
}
class blueGlass extends Glass
{
public function display()
{
echo "发射蓝光<br/>";
}
}
class Pig
{
public function display()
{
echo "猪八戒<br/>";
}
}
$light = new Light();
$red = new redGlass();
$blue = new blueGlass();
$pig = new Pig();
$light->ons($red);
$light->ons($blue);
//$light->ons($pig);