closure-php function callback parameter how to use external parameters within a callback function

Direct code, usage scenarios:
Now the code:

$gifts = $this->get_list();$gifts = array_filter($gifts,function($v) use ($customer_id){    return call_user_func(array($this,'gift_selector'),$v,$customer_id);});

If:

$gifts = $this->get_list();$gifts = array_filter($gifts,($this,'gift_selector'));

$giftIt is possible to pass in as a default parameter $this->gift_selector() , but how is an external variable $customer_id passed in?

Of course, closure you can use use ($customer_id) this when you know, but here you want to write the callback function, because it is closure too long written.

Reply content:

Direct code, usage scenarios:
Now the code:

$gifts = $this->get_list();$gifts = array_filter($gifts,function($v) use ($customer_id){    return call_user_func(array($this,'gift_selector'),$v,$customer_id);});

If:

$gifts = $this->get_list();$gifts = array_filter($gifts,($this,'gift_selector'));

$giftIt is possible to pass in as a default parameter $this->gift_selector() , but how is an external variable $customer_id passed in?

Of course, closure you can use use ($customer_id) this when you know, but here you want to write the callback function, because it is closure too long written.

phpclass Demo{    private $customer_id = 0;    public function doit()    {        $gifts = array('1', '2', '3');        $this->customer_id = 3;        $gifts = array_filter($gifts, array($this,'gift_selector'));        return $gifts;    }    private function gift_selector($v)    {        return $v==$this->customer_id ? true : false;    }}$obj    = new Demo();$gifts  = $obj->doit();var_dump($gifts);/*array (size=1)  2 => string '3' (length=1)*/

Crab Demon

Write callback hard to pass the value of the non-parameter can be achieved by the class members such as song Xiao Bei, but I personally think this is similar to the global variable delivery state, belongs to the bad code smell

My advice is to consider get_list adding the ability to filter by callback

phpfunction get_list($filter = null) {  $gifts = [];//原本的逻辑..  if(is_callable($filter)) {    $gifts = array_filter($gifts,function($gift) use ($customer_id) {      return call_user_func($filter, $gift, $customer_id);    });  }  return $gifts;}

So there is

php$this->get_list([$this,'gift_selector']);

, Gift_selector was able to receive the $gift, $customer_id parameters as

Global variables, Session/cookie, reference pass-through values

Edit
Class Property Assignment Value
$this->customer_id;

