c# - .stl file downloaded not opening or corrupt

Question

i am having problem with .stl file download in c# angular js mvc. while the file is downloading i am not able to open the file in 3d shape or anyother software supporting stl file extension.

vm.FileDownload = function (id, hash,filename) {
            var defer = $q.defer();
            threeShapeRepo.getFile(id, hash, filename).then(function (data) {
                if (data !== null) {
                    var file = new Blob([data], {
                        type: 'application/stl'
                    });
                    var fileURL = URL.createObjectURL(file);
                    var link = document.createElement('a');
                    link.href = fileURL;
                    link.target = '_blank';
                    link.download = filename;
                    document.body.appendChild(link);
                    link.click();
                    document.body.removeChild(link);
                }
                //window.URL.revokeObjectURL(url);
                defer.resolve(data);
            });
        }

From repository.js

                function getFile(id, hash, fileName) {
            var params = {
                'Id': id,
                'Hash': hash,
                'FileName': fileName
            }
            var url = 'https://' + window.location.host + '/api/' + 'ThreeShape' + '/' + 'getFileAsync';
            return $http.post(url, params, { responseType: 'blob' }).then(function (data) {
                if (data.data.Content.indexOf("validation failed")!==-1) {
                    logError(data.data.Content);
                    return null;
                }
                return data.data;
            });
        }

in c# back end code

public async Task<string> getFileAsyncInternal(GetFile request)
        {
            var response = new GetThreeShapeCasesResponse();
            IList<GetOneThreeShapeCaseResult> tempCaseList = new List<GetOneThreeShapeCaseResult>();
            IRestResponse restResponse;
            var retryCount = 0;
            HttpStatusCode statusCode;
            int numericStatusCode;
            var requestUrl = "";
            InitializeThreeShapeClient();
            var restRequest = new RestRequest(Method.GET);
            if (request.Hash != null)
            {

                requestUrl = threeShapeServerLocation + "api/cases/"+ request.Id+"/attachments/"+ request.Hash;

            }
            ThreeShapeAPIClient.BaseUrl = new Uri(requestUrl);
            var getTokenOperation = await retreive3ShapeBearerTokenInternal();
            var myToken = getTokenOperation.TokenValue;
            var tokenString = "Bearer " + myToken;
            restRequest.AddHeader("Authorization", tokenString);
            restResponse = ThreeShapeAPIClient.Execute(restRequest);
            numericStatusCode = (int)restResponse.StatusCode;
            System.Web.HttpResponse httpresponse = System.Web.HttpContext.Current.Response; ;
            if (numericStatusCode == 200)
            {
                var strResult = restResponse.Content; 
                //return strResult;
                string fileName = request.FileName;
                httpresponse.ClearContent();
                httpresponse.Clear();
                byte[] buffer = new byte[restResponse.Content.Length];
                System.Net.Mime.ContentDisposition cd = new System.Net.Mime.ContentDisposition
                {
                    FileName = fileName,
                    Inline = true  // false = prompt the user for downloading;  true = browser to try to show the file inline
                };
                httpresponse.Headers.Add("Content-Disposition", "attachment;filename="+request.FileName+ ";filename*=UTF-8''" + request.FileName);
                httpresponse.Headers.Add("Content-Length",Convert.ToString(restResponse.Content.Length));
                httpresponse.Headers.Add("Contenty-Type", ((RestSharp.RestResponseBase)restResponse).ContentType);
                httpresponse.Output.Write(restResponse.Content);
                return restResponse.Content;
            }
            else if (retryCount == 0 && numericStatusCode == 401)
            {
                response.DidError = true;
                response.ErrorMessage = restResponse.Content;
            }
            return restResponse.Content;
        }

I have been struggling to make the downloaded file open. Any kind of help is deeply appreciated. Response i am getting in content object is

Answer 1

I would start by comparing file contents of a clean copy and corrupt downloaded copy for clues. Is the downloaded copy really corrupt or is it actually empty? Do you see a pattern in the corrupt copies? etc Goodluck!