php对微信支付的回调异步处理过程

//获取返回的xml
$testxml  = file_get_contents("php://input");
//将xml转化为json格式
$jsonxml = json_encode(simplexml_load_string($testxml, 'SimpleXMLElement', LIBXML_NOCDATA));
//转成数组
$result = json_decode($jsonxml, true);
if($result){
          //如果成功返回了
         if($result['return_code'] == 'SUCCESS' && $result['result_code'] == 'SUCCESS'){
          //进行改变订单状态等操作。。。。 
   }
}

{
    "appid": "12345",
    "attach": "pay",
    "bank_type": "CFT",
    "cash_fee": "1",
    "fee_type": "CNY",
    "is_subscribe": "Y",
    "mch_id": "12345",
    "nonce_str": "dZYFpaDYRpF5rwhv",
    "openid": "onhwF1hiutUySKCsrV21A6MCtT5Q",
    "out_trade_no": "SH201808222055598628",
    "result_code": "SUCCESS",
    "return_code": "SUCCESS",
    "sign": "5A019F52BEF1C3A98AE0F1FF29D01574",
    "time_end": "20180822205606",
    "total_fee": "1",
    "trade_type": "MWEB",
    "transaction_id": "4200000171201808221550954201"
}

"result_code": "SUCCESS",
"return_code": "SUCCESS",