PHP's syntax to create an array (either indexed or assosiative) is the same, aka
$arr = [];
However, json_encode will convert an empty PHP "array" (note the quotes) to an empty JS array ([]), which is not desirable in certain situations.
Is there a way I can create an empty assosiative array in PHP, so json_encode will convert it to an empty JS object, aka {}, instead of [].
You can use stdClass:
$obj = new stdClass();
echo json_encode($obj);
This gets me the intended {} output.
Use a stdClass():
php > $x = new StdClass;
php > echo json_encode($x);
{}
Of course, once it's a stdclass, you wouldn't be able to use it as an array anymore. But this is at least one way of forcing an empty object in JSON, so you could just special-case your code:
if (count($array) == 0) {
$json = json_encode(new StdClass);
} else {
$json = json_encode($array);
}
You can just pass the JSON_FORCE_OBJECT option to the json_encode function. This will force any empty arrays to be objects as well.
JSON_FORCE_OBJECT (integer) Outputs an object rather than an array when a non-associative array is used. Especially useful when the recipient of the output is expecting an object and the array is empty. Available since PHP 5.3.0.
So:
if (empty($array)) {
$json = json_encode([], JSON_FORCE_OBJECT);
} else {
$json = json_encode($array);
}
This looks cleaner than converting an object in my opinion.
Or even
$json = json_encode($array, empty($array) ? JSON_FORCE_OBJECT : 0);
