[php] How to add property to object in PHP >= 5.3 strict mode without generating error

This has to be simple, but I can't seem to find an answer....

I have a generic stdClass object $foo with no properties. I want to add a new property $bar to it that's not already defined. If I do this:

$foo = new StdClass();
$foo->bar = '1234';

PHP in strict mode complains.

What is the proper way (outside of the class declaration) to add a property to an already instantiated object?

NOTE: I want the solution to work with the generic PHP object of type stdClass.

A little background on this issue. I'm decoding a json string which is an array of json objects. json_decode() generates an array of StdClass object. I need to manipulate these objects and add a property to each one.

Do it like this:

$foo = new stdClass();
$foo->{"bar"} = '1234';

now try:

echo $foo->bar; // should display 1234

you should use magic methods __Set and __get. Simple example:

class Foo
{
    //This array stores your properties
private $content = array();

public function __set($key, $value)
{
            //Perform data validation here before inserting data
    $this->content[$key] = $value;
    return $this;
}

public function __get($value)
{       //You might want to check that the data exists here
    return $this->$content[$value];
}

}

Of course, don't use this example as this : no security at all :)

EDIT : seen your comments, here could be an alternative based on reflection and a decorator :

 class Foo
 {
private $content = array();
private $stdInstance;

public function __construct($stdInstance)
{
    $this->stdInstance = $stdInstance;
}

public function __set($key, $value)
{
    //Reflection for the stdClass object
    $ref = new ReflectionClass($this->stdInstance);
    //Fetch the props of the object

    $props = $ref->getProperties();

    if (in_array($key, $props)) {
        $this->stdInstance->$key = $value;
    } else {
        $this->content[$key] = $value;
    }
    return $this;
}

public function __get($value)
{
    //Search first your array as it is faster than using reflection
    if (array_key_exists($value, $this->content))
    {
        return $this->content[$value];
    } else {
        $ref = new ReflectionClass($this->stdInstance);

        //Fetch the props of the object
        $props = $ref->getProperties();

        if (in_array($value, $props)) {

        return $this->stdInstance->$value;
    } else {
        throw new \Exception('No prop in here...');
    }
}
 }
}

PS : I didn't test my code, just the general idea...

If you want to edit the decoded JSON, try getting it as an associative array instead of an array of objects.

$data = json_decode($json, TRUE);

I always use this way:

$foo = (object)null; //create an empty object
$foo->bar = "12345";

echo $foo->bar; //12345

Yes, is possible to dynamically add properties to a PHP object.

This is useful when a partial object is received from javascript.

JAVASCRIPT side:

var myObject = { name = "myName" };
$.ajax({ type: "POST", url: "index.php",
    data: myObject, dataType: "json",
    contentType: "application/json;charset=utf-8"
}).success(function(datareceived){
    if(datareceived.id >= 0 ) { /* the id property has dynamically added on server side via PHP */ }
});

PHP side:

$requestString = file_get_contents('php://input');
$myObject = json_decode($requestString); // same object as was sent in the ajax call
$myObject->id = 30; // This will dynamicaly add the id property to the myObject object

OR JUST SEND A DUMMY PROPERTY from javascript that you will fill in PHP.

I don't know whether its the newer version of php, but this works. I'm using php 5.6

    <?php
    class Person
    {
       public $name;

       public function save()
       {
          print_r($this);
       }
    }

   $p = new Person;
   $p->name = "Ganga";
   $p->age = 23;

   $p->save();

This is the result. The save method actually gets the new property

    Person Object
    (
       [name] => Ganga
       [age] => 23
    )