public async Task <IActionResult> CreateAnswer([FromForm] CreateReq req) { if ((req.Formula == null || !req.Formula.IsValid()) && req.IonPeak < 0) { return(BadRequest(ApiResponse.Error("bad descriptions"))); } if (string.IsNullOrEmpty(req.Answer) || string.IsNullOrEmpty(req.Problem)) { return(BadRequest(ApiResponse.Error("please input problem and answer descriptions"))); } // save files var problemPictures = new List <string>(); var ansPictures = new List <string>(); if (req.ProbFiles != null && req.ProbFiles.Any()) { foreach (var pic in req.ProbFiles) { problemPictures.Add(await _fileUtil.CopyToServerFileAsync(pic)); } } if (req.AnsFiles != null && req.AnsFiles.Any()) { foreach (var pic in req.AnsFiles) { ansPictures.Add(await _fileUtil.CopyToServerFileAsync(pic)); } } var answer = await _repo.CreateAnswerAsync(req.Problem, req.Answer, problemPictures, ansPictures, req.Formula, req.IonPeak); return(Ok(ApiResponse.Success(ResponseUtil.AnswerConvert(answer)))); }