What is stdClass in PHP?

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  • In: Basic PHP

Please define what stdClass is.

This Question Has 13 Answeres | Orginal Question | Keira Nighly


$myNewObj->setNewVar = 'newVal';

yields a stdClass object - auto casted

I found this out today by misspelling:

$GLOBASLS['myObj']->myPropertyObj->myProperty = 'myVal';


stdClass is just a generic 'empty' class that's used when casting other types to objects. Despite what the other two answers say, stdClass is not the base class for objects in PHP. This can be demonstrated fairly easily:

class Foo{}
$foo = new Foo();
echo ($foo instanceof stdClass)?'Y':'N';
// outputs 'N'

I don't believe there's a concept of a base object in PHP

Using stdClass you can create a new object with it's own properties. Consider the following example that represents the details of a user as an associative array.

$array_user = array();
$array_user["name"] = "smith john";
$array_user["username"] = "smith";
$array_user["id"] = "1002";
$array_user["email"] = "smith@nomail.com";

If you need to represent the same details as the properties of an object, you can use stdClass as below.

$obj_user = new stdClass;
$obj_user->name = "smith john";
$obj_user->username = "smith";
$obj_user->id = "1002";
$obj_user->email = "smith@nomail.com";

If you are a Joomla developer refer this example in the Joomla docs for further understanding.

stdClass is PHP's generic empty class, kind of like Object in Java or object in Python (Edit: but not actually used as universal base class; thanks @Ciaran for pointing this out).

It is useful for anonymous objects, dynamic properties, etc.

See Dynamic Properties in PHP and StdClass for example.

stdClass is not an anonymous class or anonymous object

Answers here includes expressions that stdClass is "an anonymous class" or even "anonymous object". It's not true.

stdClass it's just a regular predefined class. You can check this using instanceof operator or function get_class. Nothing special goes here. PHP uses this class when casting other values to object.

In many cases where stdClass is used by the programmers the array is better option, because of useful functions and the fact that this usecase represents the data structure not a real object.

stdClass is a another great PHP feature. You can create a anonymous PHP class. Lets check an example.

$page=new stdClass();

now think you have a another class that will initialize with a page object and execute base on it.

class PageShow {

    public $currentpage;

    public function __construct($pageobj)
        $this->currentpage = $pageobj;

    public function show()
        echo $this->currentpage->name;
        $state = ($this->currentpage->status == 1) ? 'Active' : 'Inactive';
        echo 'This is ' . $state . ' page';

Now you have to create a new PageShow object with a Page Object.

Here no need to write a new Class Template for this you can simply use stdClass to create a Class on the fly.

$pageview=new PageShow($page);

Also worth noting, an stdClass object can be created from the use of json_decode() as well.

If you wanted to quickly create a new object to hold some data about a book. You would do something like this:

$book = new stdClass;
$book->title = "Harry Potter and the Prisoner of Azkaban";
$book->author = "J. K. Rowling";
$book->publisher = "Arthur A. Levine Books";
$book->amazon_link = "http://rads.stackoverflow.com/amzn/click/0439136369";

Please check the site - http://www.webmaster-source.com/2009/08/20/php-stdclass-storing-data-object-instead-array/ for more details.

You can also use object to cast arrays to an object of your choice:

Class Example
   public $name;
   public $age;

Now to create an object of type Example and to initialize it you can do either of these:

$example = new Example();
$example->name = "some name";
$example->age = 22;


$example = new Example();
$example = (object) ['name' => "some name", 'age' => 22];

The second method is mostly useful for initializing objects with many properties.

Actually I tried creating empty stdClass and compared the speed to empty class.

class emp{}

then proceeded creating 1000 stdClasses and emps... empty classes were done in around 1100 microseconds while stdClasses took over 1700 microseconds. So I guess its better to create your own dummy class for storing data if you want to use objects for that so badly (arrays are a lot faster for both writing and reading).

stClass is an empty class created by php itself , and should be used by php only, because it is not just an "empty" class , php uses stdClass to convert arrays to object style if you need to use stdClass , I recommend two better options : 1- use arrays (much faster than classes) 2- make your own empty class and use it

//example 1
$data=array('k1'=>'v1' , 'k2'=>'v2',....);

//example 2
//creating an empty class is faster than instances an stdClass
class data={}
$data=new data();

what makes someone to think about using the object style instead of array style???

php.net manual has a few solid explanation and examples contributed by users of what stdClass is, I especially like this one http://php.net/manual/en/language.oop5.basic.php#92123, https://stackoverflow.com/a/1434375/2352773.

stdClass is the default PHP object. stdClass has no properties, methods or parent. It does not support magic methods, and implements no interfaces.

When you cast a scalar or array as Object, you get an instance of stdClass. You can use stdClass whenever you need a generic object instance.

stdClass is NOT a base class! PHP classes do not automatically inherit from any class. All classes are standalone, unless they explicitly extend another class. PHP differs from many object-oriented languages in this respect.

You could define a class that extends stdClass, but you would get no benefit, as stdClass does nothing.

stdClass objects in use

stdClass allow you to create anonymus classes and with object casting you can also access keys of an assosiative array in OOP style. Just like you would access the regular object property.


class Example {

  private $options;

  public function __construct(Array $setup)
    // casting Array to stdClass object
    $this->options = (object) $setup;

    // access stdClass object in oop style - here transform data in OOP style using some custom method or something...
    echo $this->options->{'name'}; // ->{'key'}
    echo $this->options->surname;  // ->key


$ob1 = new Example(["name" => "John", "surname" => "Doe"]);

will echo

John Doe

I am...

Sajjad Hossain

I have five years of experience in web development sector. I love to do amazing projects and share my knowledge with all.

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