Подробное объяснение комбинированного режима шаблона проектирования PHP [игровой кейс StarCraft]

php
  //Abstract map class
  abstract class abstractMap
  {
    //The name of the map or map package
    public $name;

    //Construction method
    public function __construct($name)
    {
      $this->name = $name;
    }

    //The name of the map or map package,地图对象没有子对象,所以用空函数,直接继承
    public function getChildren(){}

    //Add sub object, map object has no sub object, so use empty function, inherit directly
    public function addChild(abstractMap $child){}

    //Displays the name of the map or map package
    public function showMapName()
    {
      echo $this->name."
";
    }

    //Display sub object, map object has no sub object, so use empty function, inherit directly
    public function showChildren(){}
  }

  //Map class, inheriting Abstract map, in which we temporarily use the method of abstract map
  class Map extends abstractMap
  {

  }

  //Map package class inherits Abstract map, in which we need to overload the method of abstract map
  class MapBag extends abstractMap
  {

    //Collection of subobjects
    public $childern;

    //Add a sub object and force the use of an abstractmap object. Of course, maps and map packages are also abstractmap objects because they inherit the abstractmap
    public function addChild(abstractMap $child)
    {
      $this->childern[] = $child;
    }

    //Add sub object
    public function function showChildren()
    {
      if (count($this->childern)>0)
      {
        foreach ($this->childern as $child)
        {
          //The name of the calling map or package
          $child->showMapName();
        }
      }
    }
  }

  //Create a new map package object. Suppose the folder name is allied. You can take a look at the interstellar map directory. It really exists
  $map1 = new MapBag('Allied');

  //Create a new map object, assuming the file name is (2) fire Walker (also real)
  $map2 = new Map('(2)Fire Walker');

  //Next, we can see the characteristics and uses of the combination pattern.

  //Suppose that the following code needs to operate on two objects, but we don't know who is the map and who is the map package

  //Add a sub object to $MAP1, which is a map, (4) the gardens
  $map1->addChild(new Map('(4)The Gardens'));

  //Show its sub objects
  $map1->showChildren();

  //Add a child object to $MAP2, which is a map. (2) fire walker. No error will be reported here, because the map inherits an empty add method
  $map2->addChild(new Map('(2)Fire Walker'));

  //Show its sub objects,也不会出错,因为地图继承了一个空的展示方法
  $map2->showChildren();

?>