........



method_exists()

 method_exists() ,       . 
  ,   TRUE,     FALSE. 
  method_exists():

bool method_exi sts (object _. string _)
   method_exists() -    :

<?php

class Vehicle {
// ...
}

 class Land extends Vehicle {
 var $fourWheel;

  function setFourWheelDrive() {
  $this->fourWeel = 1;
  }

 }
//     $r
$car = new Land;
//   "fourWheelDrive"   "Land"
//  "Vehicle",  method_exists  TRUE;
//     FALSE.
//    method_exists()  TRUE.
if (method_exists($car, "setfourWheelDrive")) :
print "This car is equipped with 4-wheel drive";
else :
print "This car is not equipped with 4-wheel drive";
endif;
?>
    method_exists() , 
   $car    setFourWheelDrive(). 
  ,         .
     FALSE    .

get_class()

 get_class()   ,       . 
  get_class():

string get_class(object _);
  get_class() -   :

<?php

class Vehicle {
}

 class Land extends Vehicle {
 }

//     $r:
$car = new Land;
//  $class_a   "Land":
$class_a = get_class($car);
echo $class_a;
?>
    $class_a   , 
      $r.

get_parent_class()

 get_parent_class()     (  ) 
    .   get_parent_dass():

string get_parent_class (object _);
      get_parent_class():

<?php

class Vehicle {
//...
}

 class Land extends Vehicle {
 //...
 }

//     $r:
$r = new Land;
//  $parent   "Vehicle":
$parent = get_parent_class($car);
?>
  get_parent_class()  $parent    "Vehicle".

is_subclass_of()

 is_subclass_of() ,       , 
     . 
  TRUE,     ,  FALSE   . 
  is_subclass_of():

bool is_subclass_of (object , string _)
   is_subdass_of():

<?php

class Vehicle {
//...
}

 class Land extends Vehicle {
 //...
 }
$auto = new Land;
//  $is_subclass  TRUE
$is_subclass = is_subclass_of($auto, "Vehicle");
?>
    $is_subclass()   , 
   $auto     Vehicle. 
   $auto    Vehicle;  $is_subclass()
    TRUE.

get_declared_classes()

 get_declared_classes()       . 
  get_declared_classes():

array get_declared_classes()
     get_declared_classes():

<?php

 class Vehicle {
 //...
 }

  class Land extends Vehicle {
  //...
  }

$declared_classes = get_declared_classes();
// $declared_classes = array("Vehicle", "Land")
?>
     ,
        PHP. 
            PHP.