feat：网络请求异常处理

example/lib/sample/dio_widget_test.dart

@@ -40,7 +40,7 @@ class _DioWidgetTestState extends State<DioWidgetTest> {
                 errorCallback: (code, msg) {
                   debugPrint("=====errorCallback");
                   setState(() {
-                    _result = msg!;
+                    _result = "code: $code meg = $msg";
                   });
                 },
               );

lib/api/base_dio.dart

@@ -105,15 +105,11 @@ abstract class BaseDio {
       );
       onNetSuccess(response, successCallback, errorCallback);
     } on DioException catch (e) {
-      if (e.response != null) {
-        logger.e(
-            "请求错误：${e.response!.statusCode} ${e.response!.requestOptions.path}");
-        if (await _httpExceptionReLogin(e.response)) return;
-      } else {
-        // Something happened in setting up or sending the request that triggered an Error
-        logger.e("请求错误：${e.error}");
+      var result = await _handleHttpException(e.response);
+      // result 为null时，已调用重新登录方法 onLoginExpire，onLoginExpire需重写
+      if (result != null) {
+        await errorCallback?.call(result["code"], result["message"]);
       }
-      await errorCallback?.call(500, "服务器请求错误");
     }
   }
 
@@ -150,17 +146,11 @@ abstract class BaseDio {
         return {"code": 400, "message": "数据解析错误"};
       }
     } on DioException catch (e) {
-      if (e.response != null) {
-        logger.e(
-            "请求错误：${e.response!.statusCode} ${e.response!.requestOptions.path}");
-        if (await _httpExceptionReLogin(e.response)) {
-          return {"code": 401, "message": "登录过期，请重新登录"};
-        }
-      } else {
-        // Something happened in setting up or sending the request that triggered an Error
-        logger.e("请求错误：${e.error}");
+      var result = await _handleHttpException(e.response);
+      // result 为null时，已调用重新登录方法 onLoginExpire，onLoginExpire需重写
+      if (result != null) {
+        return result;
       }
-      return {"code": 500, "message": "服务器请求错误"};
     }
   }
 
@@ -193,20 +183,25 @@ abstract class BaseDio {
     }
   }
 
-  /// 网关拦截重新登录
-  /// http状态码为401 & 返回体code为-100时，需重新登录 {"code":-100,"msg":"权限变更或登录过期，请重新登录"}
-  Future<bool> _httpExceptionReLogin(Response? response) async {
-    var httpCode = response?.statusCode;
-    var httpData = response?.data;
-    if (httpData != null && httpData != "") {
+  /// 处理http异常
+  Future<Map<String, dynamic>?> _handleHttpException(Response? response) async {
+    if (response == null) {
+      return {"code": -500, "message": "网络请求错误，请稍后重试"};
+    }
+    var httpCode = response.statusCode; // httpCode
+    var httpData = response.data; // httpData
+    try {
       var httpResult = await jsonTransformer.parseJson(httpData);
       if (httpCode == 401 && httpResult["code"]?.toString() == "-100") {
         logger.e("登录过期：${httpResult['msg']}");
         onLoginExpire();
-        return true;
+        return null;
       }
+      return {"code": httpCode, "message": httpResult['msg'] ?? "网络请求错误，请稍后重试"};
+    } on Exception catch (e) {
+      logger.e("请求错误：${e.toString()}");
     }
-    return false;
+    return {"code": httpCode ?? -500, "message": "网络请求错误，请稍后重试"};
   }
 }