Question

Problem: I don’t want to expose $myProperty, that is it shouldn’t be public, but I need it to be public just for __toString():

class A
{
    protected $myProperty;

    public function __toString()
    {
        return json_encode($this);
    }
}

I know that ReflectionProperty class has a method named setAccessible(), but how I’m supposed to use it before returning the string?

EDIT: as per comments, I need compatibility with PHP 5.3.x, that is no JSonSerializable class.

Answer 1

As per PHP 5.3 use get_object_vars inside the __toString() method:

public function __toString()
{
    return json_encode(get_object_vars($this));
}

Usage Demo:

class A
{
    protected $myProperty = 'hello';

    public function __toString()
    {
        return json_encode(get_object_vars($this));
    }
}

echo new A; 

Output:

{"myProperty":"hello"}

Tip: Create the JsonSerializable interface your own and implement the jsonSerialize() method your own to be upwards compatible. Call the function when you need it and/or call it inside __toString():

public function __toString()
{
    return json_encode($this->jsonSerialize());
}