public async Task AddOpTag(List <RecruitJson> recruits)
        {
            try
            {
                List <OperatorTag> ot = new List <OperatorTag>();
                foreach (RecruitJson r in recruits)
                {
                    Operator op = await applicationDb.Operators
                                  .Where(o => o.Name.ToLower().Equals(r.Name.ToLower()))
                                  .Select(o => new Operator()
                    {
                        OperatorId = o.OperatorId
                    })
                                  .SingleOrDefaultAsync();

                    if (op != null)
                    {
                        foreach (string e in r.TagList)
                        {
                            int tagId = ArknightUtil.GetTagId(e);
                            if (tagId != 0)
                            {
                                ot.Add(new OperatorTag(op.OperatorId, tagId));
                            }
                        }
                    }
                }
                await applicationDb.AddRangeAsync(ot);

                await applicationDb.SaveChangesAsync();
            }
            catch (Exception e)
            {
                throw e;
            }
        }