/// <summary>
        /// 根据不同退回场景创建运行时管理器
        /// </summary>
        /// <param name="runningActivityInstanceList">运行节点列表</param>
        /// <param name="sendbackOperation">退回类型</param>
        /// <param name="runner">执行者</param>
        /// <param name="result">结果对象</param>
        /// <returns>运行时管理器</returns>
        private static WfRuntimeManager CreateRuntimeInstanceSendbackByCase(
            List <ActivityInstanceEntity> runningActivityInstanceList,
            SendbackOperationTypeEnum sendbackOperation,
            WfAppRunner runner,
            ref WfExecutedResult result)
        {
            WfRuntimeManager rmins = new WfRuntimeManagerSendBack();

            rmins.WfExecutedResult = result = new WfExecutedResult();

            ActivityInstanceEntity runningNode = runningActivityInstanceList.Where(x => x.ActivityState == (int)ActivityStateEnum.Running).OrderBy(x => x.ID).FirstOrDefault();

            if (runningNode == null)
            {
                runningNode = runningActivityInstanceList[0];
            }
            ProcessInstanceEntity processInstance = (new ProcessInstanceManager()).GetById(runningNode.ProcessInstanceID);
            IProcessModel         processModel    = ProcessModelFactory.Create(processInstance.ProcessGUID, processInstance.Version);

            var aim = new ActivityInstanceManager();

            //以下处理,需要知道上一步是独立节点的信息
            //获取上一步流转节点信息,可能经过And, Or等路由节点
            var  tim            = new TransitionInstanceManager();
            bool hasGatewayNode = false;
            var  currentNode    = runningNode;

            var lastActivityInstanceList = tim.GetPreviousActivityInstance(currentNode, true, out hasGatewayNode).ToList();

            if (lastActivityInstanceList == null || lastActivityInstanceList.Count == 0 || lastActivityInstanceList.Count > 1)
            {
                result.Status        = WfExecutedStatus.Exception;
                result.ExceptionType = WfExceptionType.Sendback_NullOrHasTooMany;
                result.Message       = "当前没有可以退回的节点,或者有多个可以退回的节点,无法选择!";

                return(rmins);
            }

            TransitionInstanceEntity lastTaskTransitionInstance = tim.GetLastTaskTransition(runner.AppName,
                                                                                            runner.AppInstanceID, runner.ProcessGUID);

            if (lastTaskTransitionInstance.TransitionType == (short)TransitionTypeEnum.Loop)
            {
                result.Status        = WfExecutedStatus.Exception;
                result.ExceptionType = WfExceptionType.Sendback_IsLoopNode;
                result.Message       = "当前流转是自循环,无需退回!";

                return(rmins);
            }

            //设置退回节点的相关信息
            var previousActivityInstance = lastActivityInstanceList[0];

            if (previousActivityInstance.ActivityType == (short)ActivityTypeEnum.StartNode)
            {
                result.Status        = WfExecutedStatus.Exception;
                result.ExceptionType = WfExceptionType.Sendback_PreviousIsStartNode;
                result.Message       = "上一步是开始节点,无需退回!";

                return(rmins);
            }

            if (sendbackOperation == SendbackOperationTypeEnum.Normal)
            {
                //简单串行模式下的退回
                rmins = new WfRuntimeManagerSendBack();
                rmins.WfExecutedResult = result = new WfExecutedResult();

                rmins.ProcessModel = processModel;
                rmins.BackwardContext.ProcessInstance                = processInstance;
                rmins.BackwardContext.BackwardToTaskActivity         = processModel.GetActivity(previousActivityInstance.ActivityGUID);
                rmins.BackwardContext.BackwardToTaskActivityInstance = previousActivityInstance;
                rmins.BackwardContext.BackwardToTargetTransitionGUID =
                    hasGatewayNode == false ? lastTaskTransitionInstance.TransitionGUID : String.Empty;        //如果中间有Gateway节点,则没有直接相连的TransitonGUID

                rmins.BackwardContext.BackwardFromActivity         = processModel.GetActivity(runningNode.ActivityGUID);
                rmins.BackwardContext.BackwardFromActivityInstance = runningNode;
                rmins.BackwardContext.BackwardTaskReceiver         = WfBackwardTaskReceiver.Instance(previousActivityInstance.ActivityName,
                                                                                                     previousActivityInstance.EndedByUserID, previousActivityInstance.EndedByUserName);

                //封装AppUser对象
                rmins.AppRunner.AppName                = runner.AppName;
                rmins.AppRunner.AppInstanceID          = runner.AppInstanceID;
                rmins.AppRunner.ProcessGUID            = runner.ProcessGUID;
                rmins.AppRunner.UserID                 = runner.UserID;
                rmins.AppRunner.UserName               = runner.UserName;
                rmins.AppRunner.NextActivityPerformers = ActivityResource.CreateNextActivityPerformers(previousActivityInstance.ActivityGUID,
                                                                                                       previousActivityInstance.EndedByUserID,
                                                                                                       previousActivityInstance.EndedByUserName);
                rmins.ActivityResource = new ActivityResource(runner, rmins.AppRunner.NextActivityPerformers);

                return(rmins);
            }

            //如果有其它模式,没有处理到,则直接抛出异常
            throw new WorkflowException("未知的退回场景,请报告给技术支持人员!");
        }
        /// <summary>
        /// 退回操作
        /// </summary>
        /// <param name="runner">执行者</param>
        /// <param name="result">结果对象</param>
        /// <returns>运行时实例对象</returns>
        internal static WfRuntimeManager CreateRuntimeInstanceSendBack(WfAppRunner runner,
                                                                       ref WfExecutedResult result)
        {
            WfRuntimeManager rmins = new WfRuntimeManagerSendBack();

            rmins.WfExecutedResult = result = new WfExecutedResult();

            var aim = new ActivityInstanceManager();
            var runningActivityInstanceList = aim.GetRunningActivityInstanceList(runner.AppInstanceID, runner.ProcessGUID).ToList();

            SendbackOperationTypeEnum sendbackOperation = SendbackOperationTypeEnum.Default;

            //当前没有运行状态的节点存在,流程不存在,或者已经结束或取消
            if (runningActivityInstanceList == null || runningActivityInstanceList.Count() == 0)
            {
                result.Status        = WfExecutedStatus.Exception;
                result.ExceptionType = WfExceptionType.Sendback_NotInRunning;
                result.Message       = "当前没有运行状态的节点存在,流程不存在,或者已经结束或取消";

                return(rmins);
            }

            if (runningActivityInstanceList.Count() == 1)       //如果只有1个运行节点
            {
                var runningNode = runningActivityInstanceList[0];

                var activityType = EnumHelper.ParseEnum <ActivityTypeEnum>(runningNode.ActivityType.ToString());
                if (XPDLHelper.IsSimpleComponentNode(activityType) == false)
                {
                    result.Status        = WfExecutedStatus.Exception;
                    result.ExceptionType = WfExceptionType.Sendback_NotTaskNode;
                    result.Message       = "当前节点不是任务类型的节点,无法退回上一步节点!";
                    return(rmins);
                }

                if (aim.IsMineTask(runningNode, runner.UserID) == false)
                {
                    result.Status        = WfExecutedStatus.Exception;
                    result.ExceptionType = WfExceptionType.Sendback_NotMineTask;
                    result.Message       = "不是登录用户的任务,无法退回!";
                    return(rmins);
                }

                //判断当前节点是否是多实例节点
                if (runningNode.MIHostActivityInstanceID != null)
                {
                    if (runningNode.CompleteOrder == 1)
                    {
                        //只有串行模式下有CompleteOrder的值为 1
                        //串行模式多实例的第一个执行节点,此时可退回到上一步
                        sendbackOperation = SendbackOperationTypeEnum.MISFirstOneIsRunning;
                    }
                    else if (runningNode.CompleteOrder > 1)
                    {
                        //已经是中间节点,只能退回到上一步多实例子节点
                        sendbackOperation = SendbackOperationTypeEnum.MISOneIsRunning;
                    }
                    else if (runningNode.CompleteOrder == -1)
                    {
                        sendbackOperation = SendbackOperationTypeEnum.MIPOneIsRunning;
                    }
                }
                else
                {
                    sendbackOperation = SendbackOperationTypeEnum.Normal;
                }
            }
            else if (runningActivityInstanceList.Count() > 1)
            {
                var firstActivityInstance = runningActivityInstanceList[0];
                if (firstActivityInstance.MIHostActivityInstanceID != null)
                {
                    //判断多实例主节点下的子节点是否都处于待办状态,如果是,则可以退回到上一步
                    bool isAllInReadyState = true;
                    var  allChildNodeList  = aim.GetActivityMultipleInstance(firstActivityInstance.MIHostActivityInstanceID.Value,
                                                                             firstActivityInstance.ProcessInstanceID);

                    int runningCount = 0;
                    foreach (var ai in allChildNodeList)
                    {
                        if (ai.ActivityState != (short)ActivityStateEnum.Ready &&
                            ai.ActivityState != (short)ActivityStateEnum.Suspended)
                        {
                            if (ai.ActivityState == (short)ActivityStateEnum.Running)
                            {
                                runningCount++;
                            }
                            else
                            {
                                isAllInReadyState = false;
                                break;
                            }
                        }
                    }
                    if (runningCount > 1)
                    {
                        isAllInReadyState = false;
                    }

                    if (isAllInReadyState == false)
                    {
                        //部分子节点有完成的
                        sendbackOperation = SendbackOperationTypeEnum.MIPSeveralIsRunning;
                    }
                    else if (runningCount == 1)
                    {
                        if (firstActivityInstance.CompleteOrder == -1)
                        {
                            sendbackOperation = SendbackOperationTypeEnum.MIPOneIsRunning;
                        }
                        else
                        {
                            //第一个子节点处于待办状态
                            sendbackOperation = SendbackOperationTypeEnum.MISFirstOneIsRunning;
                        }
                    }
                    else if (isAllInReadyState)
                    {
                        //子节点全部处于待办状态
                        sendbackOperation = SendbackOperationTypeEnum.MIPAllIsInReadyState;
                    }
                }
                else
                {
                    //有其它非多实例的并行节点,暂时不处理,后期实现该功能
                    result.Status        = WfExecutedStatus.Exception;
                    result.ExceptionType = WfExceptionType.Sendback_NullOrHasTooMany;
                    result.Message       = "有多个可以退回的节点,而且不是多实例节点,此功能暂时不支持!";

                    return(rmins);
                }
            }

            //根据不同分支场景,创建不同撤销运行时管理器
            return(CreateRuntimeInstanceSendbackByCase(runningActivityInstanceList, sendbackOperation, runner, ref result));
        }