PHP中的范围(长度)是否有类似i的东西？

$str = "Hello, world!";
$length = strlen($str);
echo "The length of the string is: " . $length;

$array = array("apple", "banana", "cherry");
$length = count($array);
echo "The length of the array is: " . $length;

class Fruit {
  public $name;
  public $color;
}

$fruit = new Fruit();
$fruit->name = "apple";
$fruit->color = "red";

$length = count(get_object_vars($fruit));
echo "The length of the object is: " . $length;