PHP Object-oriented constructor description

This article does not repeat the object-oriented knowledge, this article focuses on the PHP constructor.
The constructor of a PHP class can be a magic cube __construct () or a function with the same name as the class, as in the following example:

  class A{     Public  function A(){        Echo ' A is constructing ... '; }  } class B{     Public  function __construct(){        Echo ' B is contructing ... '; } }$a=NewA ();//A is constructing ... $b=NewB ();//B is constructing ...

In addition, when inheriting, it should be noted that:
" subclasses can not write constructors, then use the constructor of the parent class "

  class A{    protected $name; Public  function A(){        Echo ' A is constructing...<br> '; } Public  function set_name($name){        $this->name =$name; } Public  function get_name(){        return $this->name; } } class B extends A{    /* Public Function __construct () {echo ' B is contructing...<br> '; }    */}//$a = new A (); $b=NewB ();//A is constructing ... $b->set_name (' Zhangsan ');Echo $b->get_name ();

" if the subclass writes a constructor, the constructor for the parent class is no longer called "

  class A{    protected $name; Public  function A(){        Echo ' A is constructing...<br> '; } Public  function set_name($name){        $this->name =$name; } Public  function get_name(){        return $this->name; } } class B extends A{     Public  function __construct(){        Echo ' B is contructing...<br> '; } }//$a = new A (); $b=NewB ();//Just echo ' B is contructing ... ' $b->set_name (' Zhangsan ');Echo $b->get_name ();//Zhangsan

" if the constructor of the parent class is private, it can be inherited, but the subclass must have its own constructor and explicitly write "

  class A{    protected $name;Private  function A(){        Echo ' A is constructing...<br> '; } Public  function set_name($name){        $this->name =$name; } Public  function get_name(){        return $this->name; } } class B extends A{     Public  function __construct(){        Echo ' B is contructing...<br> '; } }//$a = new A (); $b=NewB ();//B is contructing ... $b->set_name (' Zhangsan ');Echo $b->get_name ();//Zhangsan

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PHP Object-oriented constructor description