企业微信以xml的形式给服务器发送通知。具体参考：企业微信文档——事件格式

        dump(file_get_contents("php://input"));/***string(530) "<xml><ToUserName><![CDATA[ww55ca070cb9b7eb22]]></ToUserName><FromUserName><![CDATA[sys]]></FromUserName><CreateTime>1403610513</CreateTime><MsgType><![CDATA[event]]></MsgType><Event><![CDATA[change_external_chat]]></Event><ChatId><![CDATA[wrx7HUARsKwGRaQBVKPBTcEyzdHA4HrQ]]></ChatId><ChangeType><![CDATA[update]]></ChangeType><UpdateDetail><![CDATA[add_member]]></UpdateDetail><JoinScene>1</JoinScene><QuitScene>0</QuitScene><MemChangeCnt>10</MemChangeCnt></xml>"*/$xml = simplexml_load_string(file_get_contents("php://input"), 'SimpleXMLElement', LIBXML_NOCDATA);dump($xml);/***object(SimpleXMLElement)#22 (11) {["ToUserName"] => string(18) "ww55ca070cb9b7eb22"["FromUserName"] => string(3) "sys"["CreateTime"] => string(10) "1403610513"["MsgType"] => string(5) "event"["Event"] => string(20) "change_external_chat"["ChatId"] => string(32) "wrx7HUARsKwGRaQBVKPBTcEyzdHA4HrQ"["ChangeType"] => string(6) "update"["UpdateDetail"] => string(10) "add_member"["JoinScene"] => string(1) "1"["QuitScene"] => string(1) "0"["MemChangeCnt"] => string(2) "10"}**/$data = array();foreach ($xml as $k => $v) {$data[(string) $k] = (string) $v;}dump($data);/*** array(11) {["ToUserName"] => string(18) "ww55ca070cb9b7eb22"["FromUserName"] => string(3) "sys"["CreateTime"] => string(10) "1403610513"["MsgType"] => string(5) "event"["Event"] => string(20) "change_external_chat"["ChatId"] => string(32) "wrx7HUARsKwGRaQBVKPBTcEyzdHA4HrQ"["ChangeType"] => string(6) "update"["UpdateDetail"] => string(10) "add_member"["JoinScene"] => string(1) "1"["QuitScene"] => string(1) "0"["MemChangeCnt"] => string(2) "10"}* */