chat bug

application/chat/controller/AppChat.php

@@ -248,7 +248,7 @@ class AppChat extends Basic
                    'page_size'   => '15' //每页多少条
                    'self'       => 'agent_5775'
                );*/
-        if (!isset($params['target_type']) || !isset($params['from']) || !isset($params['target']) || !isset($params['last_msg_id'])) {
+        if (empty($params['target_type']) || empty($params['from']) || empty($params['target']) || !isset($params['last_msg_id'])) {
             return $this->response(ErrorCodeConst::ERROR_CODE_PARAM_NOT_EXIST, "请求参数错误");
         }
         $msgModel = new ChatMsg();