Does the Key Sequence in $response_array ever Change?

[qwertyfinger]

I note from testing of the Authorize.Net system using AIM that the $post_response returns a non-associative array of 68 elements. As the capture of a successful transaction relies on knowing which key corresponse to the response_code, if the key order is changed, the application is bound to break. Is there any warranty of any kind that such changes would never be made?

[Trevor · Accepted solution]

Yes, we guarantee that the order of return fields will not change for AIM for the version that you are using.  In fact, this order did have to change in the past and that is why we introduced the AIM versioning.  Right now, you could change your code to specify x_version=3 or x_version=3.1 and you would see a slightly different field order returned, but version 3.1 will always return data in the same order.