public IActionResult FilterEditor([FromForm] FilterEditViewModel model) { var existing = _fileDatabase.GetDocumentById(model.DocumentId); var filterSet = existing.PickFilterSet(model.PageIndex); if (filterSet is null) { return(BadRequest() !); } if (model.FilterKey is null) { return(BadRequest() !); } if (!filterSet.ContainsKey(model.FilterKey)) { return(BadRequest() !); } // Copy new values across model.CopyTo(existing); // Write back to store _fileDatabase.SaveDocumentTemplate(existing, model.DocumentId); return(Content("OK") !); }