public string SaveDesignate()
        {
            string taskid = Request.Querys("taskid");
            string user   = Request.Forms("user");

            if (!taskid.IsGuid(out Guid taskId))
            {
                return("任务ID错误!");
            }
            if (user.IsNullOrWhiteSpace())
            {
                return("没有选择要指派的人员!");
            }
            Business.FlowTask flowTask = new Business.FlowTask();
            var taskModel = flowTask.Get(taskId);

            if (null == taskModel)
            {
                return("没有找到当前任务!");
            }
            string msg = flowTask.Designate(taskModel, new Business.Organize().GetAllUsers(user));

            Business.Log.Add("指派了任务-" + taskModel.Title, taskModel.ToString() + "-" + msg, Business.Log.Type.流程运行, others: user);
            return("1".Equals(msg) ? "指派成功!" : msg);
        }