如何阅读POST响应并查找详细信息

I am coding a script to read the response given from a payment gateway after a transaction is done. http://docs.merchee.com/api/push-notifications/index.html

The example data I am getting is

$received_values = "
    status_code PAID
    subtotal 10
    success_redirect http://site.com/thanks
    tax_total 0
    total_price 10
    transaction_amount 10
    transaction_date 07/24/2012
    transaction_nmb 101888
    transaction_time 12:43:52
    zip 12345 
";

I am specifically looking for the lines transaction_nmb and status_code.

I'm thinking I do something like so:

$received_values = (array) stripslashes_deep( $_POST );

But am stuck on how I should go about confirming it.. in_array?

Thank you.

Since it looks like $received_values is a newline separated string, maybe you could use this regex (untested) to get the values?

preg_match_all('/status_code\s(\w+).+transaction_nmb\s(\d+)/',$received_values, $matches);
// PAID should be in $matches[1]
// 101888 should be in $matches[2]

Explode by newline (explode is not the most efficient but will help.

$array = explode('
', $received_values);

This will give you this each line an a array.

$array[0] //status_code PAID

Then you can just look for the answer by splitting it again or using one of php parsing functions.