I am working on mvc. I have made an editing page where descriptions of a specific title are shown along with the multiple images added with a particular description. I want to make a button that adds one more image without removing the previously uploaded images. The new image should be added along with previously uploaded images.
I tried this from the controller side.

public ActionResult EditDescriptions(List<AddStoryDTO> model, HttpPostedFileBase[] Images)
        {
            if (model != null && ModelState.IsValid)
            {
                for (int i = 0; i < model.Count; i++)
                {
                    var description = model[i];
                    var uploadedImages = Request.Files.GetMultiple($"Images_{i}");
                    List<string> imageNames = new List<string>();

                    
                    if (uploadedImages != null && uploadedImages.Count > 0 && uploadedImages[0].ContentLength > 0)
                    {
                        foreach (var image in uploadedImages)
                        {
                            if (image != null && image.ContentLength > 0)
                            {
                                var imageName = Path.GetFileName(image.FileName);
                                var path = Path.Combine(Server.MapPath("~/Areas/Admin/Content/StoryImage/"), imageName);
                                image.SaveAs(path);
                                imageNames.Add(imageName);

                            }
                        }

                       
                        description.Imagename = string.Join(",", imageNames);
                    }
                    else
                    {
                        
                        description.Imagename = model[i].Imagename;
                    }

                   
                    bll.UpdateDescriptionAndImage(description);
                }

               
                return RedirectToAction("TitleList");
            }

            return View(model);
        }