From c2c8d35c30cf0bc034a9745e987084b31d4e923e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E5=B9=B8=E7=A6=8F=E7=9A=84=E7=96=AF=E7=8B=82=E7=9A=84?=
 =?UTF-8?q?=E7=9F=B3=E5=A4=B4?= <tomsxh001@163.com>
Date: Tue, 31 Dec 2019 14:39:40 +0800
Subject: [PATCH] =?UTF-8?q?responseType=E4=B8=BAjson=EF=BC=8C=E5=B0=9D?=
 =?UTF-8?q?=E8=AF=95=E8=AE=BF=E9=97=AEresponseText=EF=BC=8C=E8=A7=A6?=
 =?UTF-8?q?=E5=8F=91=E5=BC=82=E5=B8=B8=E3=80=82?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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responseType为json，服务器端返回的engine.response为null时，尝试访问responseText，触发异常，得到undefined错误。
---
 src/fly.js | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/fly.js b/src/fly.js
index ce11d92..78bd654 100644
--- a/src/fly.js
+++ b/src/fly.js
@@ -250,7 +250,14 @@ class Fly {
                 engine.onload = () => {
                     try {
                         // The xhr of IE9 has not response field
-                        let response = engine.response || engine.responseText;
+                        var response;
+                        if (!engine.responseType || engine.responseType === "text") {
+                            response = engine.responseText;
+                        } else if (engine.responseType === "document") {
+                            response = engine.responseXML;
+                        } else {
+                            response = engine.response;
+                        }
                         if (response && options.parseJson && (engine.getResponseHeader(contentType) || "").indexOf("json") !== -1
                             // Some third engine implementation may transform the response text to json object automatically,
                             // so we should test the type of response before transforming it
@@ -285,7 +292,7 @@ class Fly {
                             onerror(e)
                         }
                     } catch (e) {
-                        onerror(new Err(e.msg, engine.status))
+                        onerror(new Err(e.msg||e.message, engine.status))
                     }
                 }