Add property to object php

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.

hakre

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asked Jul 23, 2012 at 18:32

4

If you absolutely have to add the property to the object, I believe you could cast it as an array, add your property [as a new array key], then cast it back as an object. The only time you run into stdClass objects [I believe] is when you cast an array as an object or when you create a new stdClass object from scratch [and of course when you json_decode[] something - silly me for forgetting!].

Instead of:

$foo = new StdClass[];
$foo->bar = '1234';

You'd do:

$foo = array['bar' => '1234'];
$foo = [object]$foo;

Or if you already had an existing stdClass object:

$foo = [array]$foo;
$foo['bar'] = '1234';
$foo = [object]$foo;

Also as a 1 liner:

$foo = [object] array_merge[ [array]$foo, array[ 'bar' => '1234' ] ];

answered Jul 23, 2012 at 18:45

WWWWWW

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6

Do it like this:

$foo = new stdClass[];
$foo->{"bar"} = '1234';

now try:

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

answered Sep 15, 2015 at 8:55

JM R.JM R.

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7

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];

answered Jul 23, 2012 at 18:57

gen_Ericgen_Eric

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This is another way:

$foo = [object]null; //create an empty object
$foo->bar = "12345";

echo $foo->bar; //12345

answered Aug 17, 2016 at 18:18

RagnarRagnar

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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...

answered Jul 23, 2012 at 18:37

2

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