How can I access an object property named as a var

Question

A Google APIs encoded in JSON returned an object such as this

[updated] => stdClass Object
(
 [$t] => 2010-08-18T19:17:42.026Z
)

Anyone knows how can I access the $t value?

$object->$t obviously returns

Notice: Undefined variable: t in /usr/local/...

Fatal error: Cannot access empty property in /....

Answer 1

I'm using php7 and the following works fine for me:

class User {
    public $name = 'john';
}
$u = new User();

$attr = 'name';
print $u->$attr;

Answer 2

Correct answer (also for PHP7) is:

$obj->{$field}

Answer 3

Have you tried:

$t = '$t'; // Single quotes are important.
$object->$t;

Answer 4

This ought to work:

echo $object->{'$t'};

Failing that:

$property_name = '$t';
echo $object->{$property_name};