如果子类没有定义构造函数，是否调用父构造函数？

Question

In the PHP Constructors and Destructors documentation it states

Note: Parent constructors are not called implicitly if the child class defines a constructor. In order to run a parent constructor, a call to parent::__construct() within the child constructor is required.

But what if the child class does not call a constructor, will the parent constructor still be called? Or should we create a constructor that calls the parent constructor anyway?

IE:

class BaseClass {
   function __construct() {
       print "In BaseClass constructor
";
   }
}

class SubClass extends BaseClass {
   function __construct() {
       parent::__construct();
   }
}

Answer 1

Maybe this was sort of obvious but did some looking around, and a direct answer to this question surprisingly wasn't very easy to find so here it is:

If the child class does NOT define a constructor then the parent constructor will be called.

In the example below $obj will still call the constructor from BaseClass because SubClass never called a constructor.

class BaseClass {
    function __construct() {
       print "In BaseClass constructor
";
    }
}

class SubClass extends BaseClass {
    //I do not have a constructor :(
}

$obj = new SubClass();