增加了判空

pages/index/index.js

@@ -272,9 +272,13 @@ Page({
           context.goPage('payresult');
         } else if (res.action == ACTION_ON_PAY_FAILED) {
 
+          var failedMessage = res.data;
+          if (null == failedMessage) {
+            failedMessage = "支付失败";
+          }
           context.setData({
             isPaySuccess: false,
-            payFailedReason: res.data.message
+            payFailedReason: failedMessage
           });
 
           context.goPage('payresult');