How to generate {0} json string by PHP?

Question

There is a json string and it's

["email",{},"text","xyz@x.y"]

I don't how to generate the '{}' by json_encode($data, JSON_UNESCAPED_SLASHES); I try several sample codes like:

$data = ["email", null, "text", "xyz@x.y"];  // the output is ["email",null,"text","xyz@x.y"]
$data = ["email", "", "text", "xyz@x.y"]; // the output is ["email","","text","xyz@x.y"]
$data = ["email", [], "text", "xyz@x.y"]; // the output is ["email",[],"text","xyz@x.y"]

Does anyone know how to do? Thank you. Regards.

Answer 1

$data = ["email", new stdclass, "text", "xyz@x.y"];

echo json_encode($data);

will output

["email",{},"text","xyz@x.y"]