Question

What causes json_encode() to replace periods with underscores? I can’t have it doing this in my script as it then breaks my curl calls that use the URL array.

Answer 1

When PHP receives POST/GET variables (which I assume this is about, because json_encode wont’t do it), replaces dots in keys with an underscore (a register_globals legacy I think).

Either work around it, or manually parse either $_SERVER['QUERY_STRING'] for GET‘s or file_get_contents('php://input'); for POST.