where to write php classes code example

Example 1: php create object

$x = (object) [
    'a' => 'test',
    'b' => 'test2',
    'c' => 'test3'
];
var_dump($x);

/*
object(stdClass)#1 (3) {
  ["a"]=>
  string(4) "test"
  ["b"]=>
  string(5) "test2"
  ["c"]=>
  string(5) "test3"
}
*/

Example 2: create a class in php

<?php
class Fruit {
  public $name;
  public $color;

  function __construct($name, $color) {
    $this->name = $name;
    $this->color = $color;
  }
  function get_name() {
    return $this->name;
  }
  function get_color() {
    return $this->color;
  }
}

$apple = new Fruit("Apple", "red");
echo $apple->get_name();
echo "<br>";
echo $apple->get_color();
?>