ES0en calls the function example from a string

1. call_user_func

function a($b,$c){
  echo $b;
  echo $c;
}
call_user_func('a', "111","222");
call_user_func('a', "333","444");

// According to  111 222 333 444
?>
 

It is a strange way to call a method inside a class. It is a strange way to call a method inside a class. It is a strange way to call a method inside a class.

class a {
  function b($c){
    echo $c;
  }
}
call_user_func(array("a", "b"),"111");

// According to  111
?>

2. call_user_func_array

The call_user_func_array function is similar to the call_user_func function, except that the arguments are passed in a different way to make the structure of the arguments clearer:

function a($b, $c){
  echo $b;
  echo $c;
}
call_user_func_array('a', array("111", "222"));

// According to  111 222
?>

The call_user_func_array function can also call methods within a class

Class ClassA{
  function bc($b, $c) {
      $bc = $b + $c;
    echo $bc;
  }
}
call_user_func_array(array('ClassA','bc'), array("111", "222"));

// According to  333
?>

Both the call_user_func and call_user_func_array functions support references, which makes them more functional than normal function calls:

function a(&$b){
  $b++;
}
$c = 0;
call_user_func('a', &$c);
echo $c;// According to  1
call_user_func_array('a', array(&$c));
echo $c;// According to  2