I need to send a File (image) from the frontend in Angular along with some more parameters via a POST request to my ASP.NET Core backend to upload the file to a server. The issue is that I either get an HTTP 500 Error depending on the headers I specify or, the most usual, the backend receives the FormData as an empty object.
In Angular, I first convert the Base64 image I receive to a Blob, then a File to construct the FormData (it's what the ngx-compress-image package returns when it compresses an image. Maybe there is a better way to do this too?). Then I assign the headers and send the POST request:
export class RestApiService {
token: string = 'The session token';
userID: string = 'The user ID';
UploadImage(picAsBase64: string) {
let blob = new Blob([picAsBase64], { type: 'image/png' });
let file = new File([blob], Math.random().toString(36).substr(2, 5));
let formData: FormData = new FormData();
formData.append('pfile', file);
const headers = new HttpHeaders({
'Content-Type': 'multipart/form-data',
'Accept': 'application/json'
});
let options = { headers: headers };
let body = {
'paramh': this.token,
'pfile': formData,
'pkuserid': this.userID
}
return this.http.post('api/UploadFiles/UploadFiles/', body, options).pipe(map(data => { return data; }));
}
}
Backend:
[Route("api/[controller]")]
public class UploadFilesController : Controller
{
[HttpPost("UploadFiles")]
public async Task<IActionResult> UploadFiles([FromBody]JObject data)
{
string paramh = data["paramh"].ToString();
IFormFile pfile = data["pfile"].ToObject<IFormFile>();
string pkuserid = data["pkuserid"].ToString();
...
}
}
EDIT
Okay, so I applied Tony's solution, but it didn't work at first. After some tests, I found the solution in declaring the IFormFile variable as a List like Nishant suggested and declaring every argument with [FromForm] like so:
public async Task<IActionResult> UploadFiles([FromForm]string paramh, [FromForm] string pkuserid, [FromForm]List<IFormFile> pfiles)
BUT I still have an issue, because it turns out that my IFormFile has ContentType: application/octet-stream
I don't know if this is the usual and I must convert it from the backend to some image contenttype or something like that, or if it should come from the POST request as an image/png like I declared in the Angular Blob before creating the file.
Variable screenshot
Thank you all again and hope you can still help me with this last issue.
You have to use FormData for your object also like this
let formData: FormData = new FormData();
formData.append('pfile', file);
formData.append('paramh', this.token);
formData.append('pkuserid', this.userID);
return this.http.post('api/UploadFiles/UploadFiles/', formData, options).pipe(map(data => { return data; }));
Also you have to use [FromForm] in your controller
public async Task<IActionResult> UploadFiles([FromForm]JObject data)
Both the urls aren't matching.
I have done it by using IFormFile interface
string emailModel is the Model which will be deserialized
List of IFormFile files for the list of attachments
[HttpPost]
public async Task<IActionResult> SendEmailAsync(string emailModel, List<IFormFile> files)
{
EmailModel emailModel = JsonConvert.DeserializeObject<EmailModelWith>(emailModel);
List<Attachment> attachments = new List<Attachment>();
foreach (var file in files)
{
Attachment attachment = new Attachment(file.OpenReadStream(), file.FileName, file.ContentType);
attachments.Add(attachment);
}
return Ok();
}
I need to allow image upload in my AngularJS + WebAPI project. to achieve this I am using ng-file-upload according to this sample code: http://monox.mono-software.com/blog/post/Mono/233/Async-upload-using-angular-file-upload-directive-and-net-WebAPI-service/
with a few adjustments to the post code to look like this:
$scope.onFileSelect = function ($files) {
console.log("on file select is running!");
//$files: an array of files selected, each file has name, size, and type.
for (var i = 0; i < $files.length; i++) {
var $file = $files[i];
(function (index) {
Upload.upload({
url: "/api/Uploads/Upload", // webapi url
method: "POST",
file: $file
}).progress(function (evt) {
// get upload percentage
console.log('percent: ' + parseInt(100.0 * evt.loaded / evt.total));
}).success(function (data, status, headers, config) {
// file is uploaded successfully
console.log(data);
}).error(function (data, status, headers, config) {
// file failed to upload
console.log(data);
});
})(i);
}
}
I have quite a few web API controllers already and I added a new one according to the code sample in the link above (that inherits from System.web.http.ApiController instead of the "regular" Microsoft.AspNet.Mvc.Controller class):
[Route("api/[controller]")]
public class UploadsController : ApiController
{
[HttpPost] // This is from System.Web.Http, and not from System.Web.Mvc
public async Task<HttpResponseMessage> Upload()
{
if (!Request.Content.IsMimeMultipartContent())
{
this.Request.CreateResponse(HttpStatusCode.UnsupportedMediaType);
}
var provider = GetMultipartProvider();
var result = await Request.Content.ReadAsMultipartAsync(provider);
// On upload, files are given a generic name like "BodyPart_26d6abe1-3ae1-416a-9429-b35f15e6e5d5"
// so this is how you can get the original file name
var originalFileName = GetDeserializedFileName(result.FileData.First());
// uploadedFileInfo object will give you some additional stuff like file length,
// creation time, directory name, a few filesystem methods etc..
var uploadedFileInfo = new FileInfo(result.FileData.First().LocalFileName);
// Through the request response you can return an object to the Angular controller
// You will be able to access this in the .success callback through its data attribute
// If you want to send something to the .error callback, use the HttpStatusCode.BadRequest instead
var returnData = "ReturnTest";
return this.Request.CreateResponse(HttpStatusCode.OK, new { returnData });
}
The problem is, i keep getting "404 not found" when posting.
I tried:
all stack overflow answers
online answers
removing the content of the "Upload" function, and changing to MVC's Controller base class -> still same result.
changing the name of "Upload" method to "Post" and posting to "/api/uploads" -> same 404.
Please help!
thanks!
EDIT
this is the browser "Network" tab:
I am using HTTPS
this was tested "live" (without localhost) = same result.
EDIT2
my routes:
app.UseMvc(routes =>
{
routes.MapRoute(
name: "default",
template: "{controller=Home}/{action=Index}/{id?}");
});
these are the only routes that are declared.
EDIT3
I am 100% sure the problem is me using "ApiController" as base class instead of "Controller". i added a new controller and i can access it no problem. now just making it work as i don't have " Request.Content " in "Controller" - any ideas?
I see 2 possibilities to make it work:
pass HttpRequestMessage as a parameter to the method:
public async Task Post([FromBody]HttpRequestMessage request)
but i am getting HTTP 500 as i don't know how to pass from angular's POST.
or:
get Request.Content to resolve under Controller (no idea how).
has someone managed to do this? thanks!
I was able to solve the problem i posted in EDIT3 by using:
if (Request.Form.Files != null && Request.Form.Files.Count > 0)
{
var file = Request.Form.Files[0];
var contentType = file.ContentType;
using (var fileStream = file.OpenReadStream())
{
using (var memoryStream = new MemoryStream())
{
await fileStream.CopyToAsync(memoryStream);
FileStream newFS = new FileStream(Settings.UserImagesDir + "\\name.png", FileMode.Create);
memoryStream.WriteTo(newFS);
newFS.Close();
}
}
}
and all this in a regular web api controller that inherits from Controller.
thanks everyone for your help, although no one solved it you all pushed me in the right direction.
The problem is that your routing is misconfigured for the URL /api/Uploads/Upload. In order to make it match, you have to specify a template for the method Upload, since it is not actually named after an HTTP method.
[HttpPost("upload")]
public async Task<HttpResponseMessage> Upload()
{
// code omitted...
}
This has been driving me nuts. I have a page where I need to make a JSON post to a controller, it will process it and return an excel file for download. So far it appears to be running correctly, but when it returns to the ajax call, I get an parsererror and the message "Unexpected token P." I have tried so many different configurations and call methods (standard MVC ActionRequest to WebApi post) and none of them change. Here is the code I'm running.
JavaScript:
var treatmentplan = {"PlanRecordStatusId":"1","PlanRecordDateBegin":"","PlanRecordDateEnd":"","ClientClaimNumber":"","PatientNumber":0,"requestAction":3};
$.ajax({
//global: true,
//url: '/home/ExcelRpt',
url: '/api/TreatmentPlanExcel',
type: 'POST',
dataType: 'json',
data: treatmentplan,
//contentType: 'application/json; charset=utf-8',
success: function (data) {
//var msg = data.Message;
//$('#results').html(msg);
$("#tmpFrame").attr('src', 'URL-TO-EXCEL-FILE');
}
, error: function (jqXHR, exception, error) {
if (jqXHR.status === 0) {
alert('Not connect.n Verify Network.');
} else if (jqXHR.status == 404) {
alert('Requested page not found. [404]');
} else if (jqXHR.status == 500) {
alert('Internal Server Error [500].');
} else if (exception === 'parsererror') {
alert('Requested JSON parse failed.');
} else if (exception === 'timeout') {
alert('Time out error.');
} else if (exception === 'abort') {
alert('Ajax request aborted.');
} else {
alert('Uncaught Error.n' + jqXHR.responseText);
}
$('#log').html(error.message);
}
});
Here is the C# code (both WebApi and MVC controller version), I am not going to include my ToExcel extension, I know this part works it's just a matter of getting it to download when it's returned. It is reaching this code, generates data and returning. I just need to see what the heck is going on. If there is a prefered way of making the call, let me know as well (WebApi or MVC)
C#
Web Api version
public HttpResponseMessage Post(TreatmentPlanRequest tpRequest) {
tpRequest.Verify();
List<TreatmentPlan> tpl = DataAccess.GetReportDap(tpRequest).ToList();
HttpResponseMessage result = new HttpResponseMessage(HttpStatusCode.OK);
var contentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
var package = tpl.ToExcel("TreatmentReport");
var fileStream = new MemoryStream();
package.SaveAs(fileStream);
fileStream.Position = 0;
result.Content = new StreamContent(fileStream);
result.Content.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");
return result;
}
Here is the MVC controller version
[HttpPost]
public ActionResult ExcelRpt(TreatmentPlanRequest tpRequest) {
tpRequest.Verify();
List<TreatmentPlan> tpl = DataAccess.GetReportDap(tpRequest).ToList();
var contentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
var package = tpl.ToExcel("TreatmentReport");
var fileStream = new MemoryStream();
package.SaveAs(fileStream);
fileStream.Position = 0;
var fsr = new FileStreamResult(fileStream, contentType);
fsr.FileDownloadName = "TreatmentReport";
return fsr;
}
From here, I have no clue as to why this isn't working. I have searched high and low on Google on how to do this in MVC (I use to do this with web forms and never had an issue). I am guessing my issue is on the return or
Change your Success method to open a new window with the URL instead of setting a frame in the current window.
So this:
$("#tmpFrame").attr('src', 'URL-TO-EXCEL-FILE');
becomes:
window.open('URL-TO-EXCEL-FILE');
In the vast majority of cases, this should do exactly what you're looking for. Occasionally, depending on specific browser settings, users may get a "Popup Blocked" message, but that rarely happens in this scenario in the apps that I've worked with.
EDIT:
After additional clarification, there is a second issue. Data returned from the server must be in the same format as the .ajax() method is expecting it, in this case 'JSON'. Instead of returning a FileStreamResult from your Action, try returning a JSON object which has the URL you'll need to call to generate the Excel file.
return Json(new { URL = 'URL-TO-EXCEL-FILE' });
Then, follow the suggestion in my original response.
I would like to thank Kris Hatcher for the solution on this. He suggested making two ActionResults. One that builds a query string from the parameters of the initial request. It returns a full URL with the parameters. It then does a Window.Open() using the returned url.
With all the examples I found, this was the only one that worked for me. Here's how the code works.
JavaScript:
function TestWebApiReport() {
var reportData = GetReport();
$.ajax({
url: '/home/ExcelResults'
, data: reportData
, type: 'POST'
, dataType: 'json'
, success: function (data) {
window.open(data.URL);
}, error: function (jqXHR, exception, error) {
alert("GRRRRRR!!!")
}
});
}
It creates the JSON data, then posts it to a JsonResult. Here's the controller code.
C#
[HttpPost]
public JsonResult ExcelResults(ReportRequest tpRequest) {
StringBuilder sb = new StringBuilder();
bool firstIn = true;
sb.AppendFormat("{0}/Home/ExcelRpt", Request.Url.Scheme + "://" + Request.Url.Authority);
foreach (var prop in tpRequest.GetType().GetProperties()) {
if (prop.GetValue(tpRequest, null) != null) {
if (firstIn) {
sb.AppendFormat("?");
firstIn = false;
} else {
sb.AppendFormat("&");
}
sb.AppendFormat("{0}={1}", prop.Name, prop.GetValue(tpRequest, null));
}
}
return Json(new { URL = sb.ToString() });
}
You go back to the JavaScript, you'll see the return data uses the URL to do a Window.Open(). Then the excel file is created. Here's the last call (ActionResult).
[HttpGet]
public ActionResult ExcelRpt(ReportRequest tpRequest) {
if (tpRequest.requestAction != RequestAction.Report) {
throw new Exception("Did not use action request type of 'Report'.");
}
tpRequest.requestAction = RequestAction.Report;
List<Report> tpl = DataAccess.GetReportDap(tpRequest).ToList();
var contentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
var package = tpl.ToExcel("Report");
var fileStream = new MemoryStream();
package.SaveAs(fileStream);
fileStream.Position = 0;
var fsr = new FileStreamResult(fileStream, contentType);
fsr.FileDownloadName = "TreatmentReport.xlsx";
return fsr;
}
ReportRequest is a class I have and ToExcel(), I extended the List item. Now this works pretty well.
I have a large(ish) form in MVC.
I need to be able to generate an excel file containing data from a subset of that form.
The tricky bit is that this shouldn't affect the rest of the form and so I want to do it via AJAX. I've come across a few questions on SO that seem to be related, but I can't quite work out what the answers mean.
This one seems the closest to what I'm after: asp-net-mvc-downloading-excel - but I'm not sure I understand the response, and it is a couple years old now. I also came across another article (can't find it anymore) about using an iframe to handle the file download, but I'm not sure how to get this working with MVC.
My excel file returns fine if I'm doing a full post back but I can't get it working with AJAX in mvc.
You can't directly return a file for download via an AJAX call so, an alternative approach is to to use an AJAX call to post the related data to your server. You can then use server side code to create the Excel File (I would recommend using EPPlus or NPOI for this although it sounds as if you have this part working).
UPDATE September 2016
My original answer (below) was over 3 years old, so I thought I would update as I no longer create files on the server when downloading files via AJAX however, I have left the original answer as it may be of some use still depending on your specific requirements.
A common scenario in my MVC applications is reporting via a web page that has some user configured report parameters (Date Ranges, Filters etc.). When the user has specified the parameters they post them to the server, the report is generated (say for example an Excel file as output) and then I store the resulting file as a byte array in the TempData bucket with a unique reference. This reference is passed back as a Json Result to my AJAX function that subsequently redirects to separate controller action to extract the data from TempData and download to the end users browser.
To give this more detail, assuming you have a MVC View that has a form bound to a Model class, lets call the Model ReportVM.
First, a controller action is required to receive the posted model, an example would be:
public ActionResult PostReportPartial(ReportVM model){
// Validate the Model is correct and contains valid data
// Generate your report output based on the model parameters
// This can be an Excel, PDF, Word file - whatever you need.
// As an example lets assume we've generated an EPPlus ExcelPackage
ExcelPackage workbook = new ExcelPackage();
// Do something to populate your workbook
// Generate a new unique identifier against which the file can be stored
string handle = Guid.NewGuid().ToString();
using(MemoryStream memoryStream = new MemoryStream()){
workbook.SaveAs(memoryStream);
memoryStream.Position = 0;
TempData[handle] = memoryStream.ToArray();
}
// Note we are returning a filename as well as the handle
return new JsonResult() {
Data = new { FileGuid = handle, FileName = "TestReportOutput.xlsx" }
};
}
The AJAX call that posts my MVC form to the above controller and receives the response looks like this:
$ajax({
cache: false,
url: '/Report/PostReportPartial',
data: _form.serialize(),
success: function (data){
var response = JSON.parse(data);
window.location = '/Report/Download?fileGuid=' + response.FileGuid
+ '&filename=' + response.FileName;
}
})
The controller action to handle the downloading of the file:
[HttpGet]
public virtual ActionResult Download(string fileGuid, string fileName)
{
if(TempData[fileGuid] != null){
byte[] data = TempData[fileGuid] as byte[];
return File(data, "application/vnd.ms-excel", fileName);
}
else{
// Problem - Log the error, generate a blank file,
// redirect to another controller action - whatever fits with your application
return new EmptyResult();
}
}
One other change that could easily be accommodated if required is to pass the MIME Type of the file as a third parameter so that the one Controller action could correctly serve a variety of output file formats.
This removes any need for any physical files to created and stored on the server, so no housekeeping routines required and once again this is seamless to the end user.
Note, the advantage of using TempData rather than Session is that once TempData is read the data is cleared so it will be more efficient in terms of memory usage if you have a high volume of file requests. See TempData Best Practice.
ORIGINAL Answer
You can't directly return a file for download via an AJAX call so, an alternative approach is to to use an AJAX call to post the related data to your server. You can then use server side code to create the Excel File (I would recommend using EPPlus or NPOI for this although it sounds as if you have this part working).
Once the file has been created on the server pass back the path to the file (or just the filename) as the return value to your AJAX call and then set the JavaScript window.location to this URL which will prompt the browser to download the file.
From the end users perspective, the file download operation is seamless as they never leave the page on which the request originates.
Below is a simple contrived example of an ajax call to achieve this:
$.ajax({
type: 'POST',
url: '/Reports/ExportMyData',
data: '{ "dataprop1": "test", "dataprop2" : "test2" }',
contentType: 'application/json; charset=utf-8',
dataType: 'json',
success: function (returnValue) {
window.location = '/Reports/Download?file=' + returnValue;
}
});
url parameter is the Controller/Action method where your code will create the Excel file.
data parameter contains the json data that would be extracted from the form.
returnValue would be the file name of your newly created Excel file.
The window.location command redirects to the Controller/Action method that actually returns your file for download.
A sample controller method for the Download action would be:
[HttpGet]
public virtual ActionResult Download(string file)
{
string fullPath = Path.Combine(Server.MapPath("~/MyFiles"), file);
return File(fullPath, "application/vnd.ms-excel", file);
}
My 2 cents - you don't need to store the excel as a physical file on the server - instead, store it in the (Session) Cache. Use a uniquely generated name for your Cache variable (that stores that excel file) - this will be the return of your (initial) ajax call. This way you don't have to deal with file access issues, managing (deleting) the files when not needed, etc. and, having the file in the Cache, is faster to retrieve it.
I was recently able to accomplish this in MVC (although there was no need to use AJAX) without creating a physical file and thought I'd share my code:
Super simple JavaScript function (datatables.net button click triggers this):
function getWinnersExcel(drawingId) {
window.location = "/drawing/drawingwinnersexcel?drawingid=" + drawingId;
}
C# Controller code:
public FileResult DrawingWinnersExcel(int drawingId)
{
MemoryStream stream = new MemoryStream(); // cleaned up automatically by MVC
List<DrawingWinner> winnerList = DrawingDataAccess.GetWinners(drawingId); // simple entity framework-based data retrieval
ExportHelper.GetWinnersAsExcelMemoryStream(stream, winnerList, drawingId);
string suggestedFilename = string.Format("Drawing_{0}_Winners.xlsx", drawingId);
return File(stream, "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet.main+xml", suggestedFilename);
}
In the ExportHelper class I do use a 3rd party tool (GemBox.Spreadsheet) to generate the Excel file and it has a Save to Stream option. That being said, there are a number of ways to create Excel files that can easily be written to a memory stream.
public static class ExportHelper
{
internal static void GetWinnersAsExcelMemoryStream(MemoryStream stream, List<DrawingWinner> winnerList, int drawingId)
{
ExcelFile ef = new ExcelFile();
// lots of excel worksheet building/formatting code here ...
ef.SaveXlsx(stream);
stream.Position = 0; // reset for future read
}
}
In IE, Chrome, and Firefox, the browser prompts to download the file and no actual navigation occurs.
First Create the controller action that will create the Excel File
[HttpPost]
public JsonResult ExportExcel()
{
DataTable dt = DataService.GetData();
var fileName = "Excel_" + DateTime.Now.ToString("yyyyMMddHHmm") + ".xls";
//save the file to server temp folder
string fullPath = Path.Combine(Server.MapPath("~/temp"), fileName);
using (var exportData = new MemoryStream())
{
//I don't show the detail how to create the Excel, this is not the point of this article,
//I just use the NPOI for Excel handler
Utility.WriteDataTableToExcel(dt, ".xls", exportData);
FileStream file = new FileStream(fullPath, FileMode.Create, FileAccess.Write);
exportData.WriteTo(file);
file.Close();
}
var errorMessage = "you can return the errors in here!";
//return the Excel file name
return Json(new { fileName = fileName, errorMessage = "" });
}
then create the Download action
[HttpGet]
[DeleteFileAttribute] //Action Filter, it will auto delete the file after download,
//I will explain it later
public ActionResult Download(string file)
{
//get the temp folder and file path in server
string fullPath = Path.Combine(Server.MapPath("~/temp"), file);
//return the file for download, this is an Excel
//so I set the file content type to "application/vnd.ms-excel"
return File(fullPath, "application/vnd.ms-excel", file);
}
if you want to delete the file after downloaded create this
public class DeleteFileAttribute : ActionFilterAttribute
{
public override void OnResultExecuted(ResultExecutedContext filterContext)
{
filterContext.HttpContext.Response.Flush();
//convert the current filter context to file and get the file path
string filePath = (filterContext.Result as FilePathResult).FileName;
//delete the file after download
System.IO.File.Delete(filePath);
}
}
and finally ajax call from you MVC Razor view
//I use blockUI for loading...
$.blockUI({ message: '<h3>Please wait a moment...</h3>' });
$.ajax({
type: "POST",
url: '#Url.Action("ExportExcel","YourController")', //call your controller and action
contentType: "application/json; charset=utf-8",
dataType: "json",
}).done(function (data) {
//console.log(data.result);
$.unblockUI();
//get the file name for download
if (data.fileName != "") {
//use window.location.href for redirect to download action for download the file
window.location.href = "#Url.RouteUrl(new
{ Controller = "YourController", Action = "Download"})/?file=" + data.fileName;
}
});
I used the solution posted by CSL but I would recommend you dont store the file data in Session during the whole session. By using TempData the file data is automatically removed after the next request (which is the GET request for the file). You could also manage removal of the file data in Session in download action.
Session could consume much memory/space depending on SessionState storage and how many files are exported during the session and if you have many users.
I've updated the serer side code from CSL to use TempData instead.
public ActionResult PostReportPartial(ReportVM model){
// Validate the Model is correct and contains valid data
// Generate your report output based on the model parameters
// This can be an Excel, PDF, Word file - whatever you need.
// As an example lets assume we've generated an EPPlus ExcelPackage
ExcelPackage workbook = new ExcelPackage();
// Do something to populate your workbook
// Generate a new unique identifier against which the file can be stored
string handle = Guid.NewGuid().ToString()
using(MemoryStream memoryStream = new MemoryStream()){
workbook.SaveAs(memoryStream);
memoryStream.Position = 0;
TempData[handle] = memoryStream.ToArray();
}
// Note we are returning a filename as well as the handle
return new JsonResult() {
Data = new { FileGuid = handle, FileName = "TestReportOutput.xlsx" }
};
}
[HttpGet]
public virtual ActionResult Download(string fileGuid, string fileName)
{
if(TempData[fileGuid] != null){
byte[] data = TempData[fileGuid] as byte[];
return File(data, "application/vnd.ms-excel", fileName);
}
else{
// Problem - Log the error, generate a blank file,
// redirect to another controller action - whatever fits with your application
return new EmptyResult();
}
}
using ClosedXML.Excel;
public ActionResult Downloadexcel()
{
var Emplist = JsonConvert.SerializeObject(dbcontext.Employees.ToList());
DataTable dt11 = (DataTable)JsonConvert.DeserializeObject(Emplist, (typeof(DataTable)));
dt11.TableName = "Emptbl";
FileContentResult robj;
using (XLWorkbook wb = new XLWorkbook())
{
wb.Worksheets.Add(dt11);
using (MemoryStream stream = new MemoryStream())
{
wb.SaveAs(stream);
var bytesdata = File(stream.ToArray(), "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet", "myFileName.xlsx");
robj = bytesdata;
}
}
return Json(robj, JsonRequestBehavior.AllowGet);
}
$.ajax({
type: "GET",
url: "/Home/Downloadexcel/",
contentType: "application/json; charset=utf-8",
data: null,
success: function (Rdata) {
debugger;
var bytes = new Uint8Array(Rdata.FileContents);
var blob = new Blob([bytes], { type: "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" });
var link = document.createElement('a');
link.href = window.URL.createObjectURL(blob);
link.download = "myFileName.xlsx";
link.click();
},
error: function (err) {
}
});
The accepted answer didn't quite work for me as I got a 502 Bad Gateway result from the ajax call even though everything seemed to be returning fine from the controller.
Perhaps I was hitting a limit with TempData - not sure, but I found that if I used IMemoryCache instead of TempData, it worked fine, so here is my adapted version of the code in the accepted answer:
public ActionResult PostReportPartial(ReportVM model){
// Validate the Model is correct and contains valid data
// Generate your report output based on the model parameters
// This can be an Excel, PDF, Word file - whatever you need.
// As an example lets assume we've generated an EPPlus ExcelPackage
ExcelPackage workbook = new ExcelPackage();
// Do something to populate your workbook
// Generate a new unique identifier against which the file can be stored
string handle = Guid.NewGuid().ToString();
using(MemoryStream memoryStream = new MemoryStream()){
workbook.SaveAs(memoryStream);
memoryStream.Position = 0;
//TempData[handle] = memoryStream.ToArray();
//This is an equivalent to tempdata, but requires manual cleanup
_cache.Set(handle, memoryStream.ToArray(),
new MemoryCacheEntryOptions().SetSlidingExpiration(TimeSpan.FromMinutes(10)));
//(I'd recommend you revise the expiration specifics to suit your application)
}
// Note we are returning a filename as well as the handle
return new JsonResult() {
Data = new { FileGuid = handle, FileName = "TestReportOutput.xlsx" }
};
}
AJAX call remains as with the accepted answer (I made no changes):
$ajax({
cache: false,
url: '/Report/PostReportPartial',
data: _form.serialize(),
success: function (data){
var response = JSON.parse(data);
window.location = '/Report/Download?fileGuid=' + response.FileGuid
+ '&filename=' + response.FileName;
}
})
The controller action to handle the downloading of the file:
[HttpGet]
public virtual ActionResult Download(string fileGuid, string fileName)
{
if (_cache.Get<byte[]>(fileGuid) != null)
{
byte[] data = _cache.Get<byte[]>(fileGuid);
_cache.Remove(fileGuid); //cleanup here as we don't need it in cache anymore
return File(data, "application/vnd.ms-excel", fileName);
}
else
{
// Something has gone wrong...
return View("Error"); // or whatever/wherever you want to return the user
}
}
...
Now there is some extra code for setting up MemoryCache...
In order to use "_cache" I injected in the constructor for the controller like so:
using Microsoft.Extensions.Caching.Memory;
namespace MySolution.Project.Controllers
{
public class MyController : Controller
{
private readonly IMemoryCache _cache;
public LogController(IMemoryCache cache)
{
_cache = cache;
}
//rest of controller code here
}
}
And make sure you have the following in ConfigureServices in Startup.cs:
services.AddDistributedMemoryCache();
$.ajax({
global: false,
url: SitePath + "/User/ExportTeamMembersInExcel",
"data": { 'UserName': UserName, 'RoleId': RoleId, UserIds: AppraseeId },
"type": "POST",
"dataType": "JSON",
"success": function (result) {
var bytes = new Uint8Array(result.FileContents);
var blob = new Blob([bytes], { type: "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" });
var link = document.createElement('a');
link.href = window.URL.createObjectURL(blob);
link.download = "myFileName.xlsx";
link.click();
},
"error": function () {
alert("error");
}
})
[HttpPost]
public JsonResult ExportTeamMembersInExcel(string UserName, long? RoleId, string[] UserIds)
{
MemoryStream stream = new MemoryStream();
FileContentResult robj;
DataTable data = objuserservice.ExportTeamToExcel(UserName, RoleId, UserIds);
using (XLWorkbook wb = new XLWorkbook())
{
wb.Worksheets.Add(data, "TeamMembers");
using (stream)
{
wb.SaveAs(stream);
}
}
robj = File(stream.ToArray(), System.Net.Mime.MediaTypeNames.Application.Octet, "TeamMembers.xlsx");
return Json(robj, JsonRequestBehavior.AllowGet);
}
I may sound quite naive, and may attract quite a criticism, but here's how I did it,
(It doesn't involve ajax for export, but it doesn't do a full postback either )
Thanks for this post and this answer.
Create a simple controller
public class HomeController : Controller
{
/* A demo action
public ActionResult Index()
{
return View(model);
}
*/
[HttpPost]
public FileResult ExportData()
{
/* An example filter
var filter = TempData["filterKeys"] as MyFilter;
TempData.Keep(); */
var someList = db.GetDataFromDb(/*filter*/) // filter as an example
/*May be here's the trick, I'm setting my filter in TempData["filterKeys"]
in an action,(GetFilteredPartial() illustrated below) when 'searching' for the data,
so do not really need ajax here..to pass my filters.. */
//Some utility to convert list to Datatable
var dt = Utility.ConvertToDataTable(someList);
// I am using EPPlus nuget package
using (ExcelPackage pck = new ExcelPackage())
{
ExcelWorksheet ws = pck.Workbook.Worksheets.Add("Sheet1");
ws.Cells["A1"].LoadFromDataTable(dt, true);
using (var memoryStream = new MemoryStream())
{
pck.SaveAs(memoryStream);
return File(memoryStream.ToArray(),
"application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
"ExportFileName.xlsx");
}
}
}
//This is just a supporting example to illustrate setting up filters ..
/* [HttpPost]
public PartialViewResult GetFilteredPartial(MyFilter filter)
{
TempData["filterKeys"] = filter;
var filteredData = db.GetConcernedData(filter);
var model = new MainViewModel();
model.PartialViewModel = filteredData;
return PartialView("_SomePartialView", model);
} */
}
And here are the Views..
/*Commenting out the View code, in order to focus on the imp. code
#model Models.MainViewModel
#{Layout...}
Some code for, say, a partial View
<div id="tblSampleBody">
#Html.Partial("_SomePartialView", Model.PartialViewModel)
</div>
*/
//The actual part.. Just **posting** this bit of data from the complete View...
//Here, you are not posting the full Form..or the complete View
#using (Html.BeginForm("ExportData", "Home", FormMethod.Post))
{
<input type="submit" value="Export Data" />
}
//...
//</div>
/*And you may require to pass search/filter values.. as said in the accepted answer..
That can be done while 'searching' the data.. and not while
we need an export..for instance:-
<script>
var filterData = {
SkipCount: someValue,
TakeCount: 20,
UserName: $("#UserName").val(),
DepartmentId: $("#DepartmentId").val(),
}
function GetFilteredData() {
$("#loader").show();
filterData.SkipCount = 0;
$.ajax({
url: '#Url.Action("GetFilteredPartial","Home")',
type: 'POST',
dataType: "html",
data: filterData,
success: function (dataHTML) {
if ((dataHTML === null) || (dataHTML == "")) {
$("#tblSampleBody").html('<tr><td>No Data Returned</td></tr>');
$("#loader").hide();
} else {
$("#tblSampleBody").html(dataHTML);
$("#loader").hide();
}
}
});
}
</script>*/
The whole point of the trick seems that, we are posting a form (a part of the Razor View ) upon which we are calling an Action method, which returns: a FileResult, and this FileResult returns the Excel File..
And for posting the filter values, as said, ( and if you require to), I am making a post request to another action, as has been attempted to describe..
This thread helped me create my own solution that I will share here. I was using a GET ajax request at first without issues but it got to a point where the request URL length was exceeded so I had to swith to a POST.
The javascript uses JQuery file download plugin and consists of 2 succeeding calls. One POST (To send params) and one GET to retreive the file.
function download(result) {
$.fileDownload(uri + "?guid=" + result,
{
successCallback: onSuccess.bind(this),
failCallback: onFail.bind(this)
});
}
var uri = BASE_EXPORT_METADATA_URL;
var data = createExportationData.call(this);
$.ajax({
url: uri,
type: 'POST',
contentType: 'application/json',
data: JSON.stringify(data),
success: download.bind(this),
fail: onFail.bind(this)
});
Server side
[HttpPost]
public string MassExportDocuments(MassExportDocumentsInput input)
{
// Save query for file download use
var guid = Guid.NewGuid();
HttpContext.Current.Cache.Insert(guid.ToString(), input, null, DateTime.Now.AddMinutes(5), Cache.NoSlidingExpiration);
return guid.ToString();
}
[HttpGet]
public async Task<HttpResponseMessage> MassExportDocuments([FromUri] Guid guid)
{
//Get params from cache, generate and return
var model = (MassExportDocumentsInput)HttpContext.Current.Cache[guid.ToString()];
..... // Document generation
// to determine when file is downloaded
HttpContext.Current
.Response
.SetCookie(new HttpCookie("fileDownload", "true") { Path = "/" });
return FileResult(memoryStream, "documents.zip", "application/zip");
}
CSL's answer was implemented in a project I'm working on but the problem I incurred was scaling out on Azure broke our file downloads. Instead, I was able to do this with one AJAX call:
SERVER
[HttpPost]
public FileResult DownloadInvoice(int id1, int id2)
{
//necessary to get the filename in the success of the ajax callback
HttpContext.Response.Headers.Add("Access-Control-Expose-Headers", "Content-Disposition");
byte[] fileBytes = _service.GetInvoice(id1, id2);
string fileName = "Invoice.xlsx";
return File(fileBytes, System.Net.Mime.MediaTypeNames.Application.Octet, fileName);
}
CLIENT
(modified version of Handle file download from ajax post)
$("#downloadInvoice").on("click", function() {
$("#loaderInvoice").removeClass("d-none");
var xhr = new XMLHttpRequest();
var params = [];
xhr.open('POST', "#Html.Raw(Url.Action("DownloadInvoice", "Controller", new { id1 = Model.Id1, id2 = Model.Id2 }))", true);
xhr.responseType = 'arraybuffer';
xhr.onload = function () {
if (this.status === 200) {
var filename = "";
var disposition = xhr.getResponseHeader('Content-Disposition');
if (disposition && disposition.indexOf('attachment') !== -1) {
var filenameRegex = /filename[^;=\n]*=((['"]).*?\2|[^;\n]*)/;
var matches = filenameRegex.exec(disposition);
if (matches != null && matches[1]) filename = matches[1].replace(/['"]/g, '');
}
var type = xhr.getResponseHeader('Content-Type');
var blob = typeof File === 'function'
? new File([this.response], filename, { type: type })
: new Blob([this.response], { type: type });
if (typeof window.navigator.msSaveBlob !== 'undefined') {
// IE workaround for "HTML7007: One or more blob URLs were revoked by closing the blob for which they were created. These URLs will no longer resolve as the data backing the URL has been freed."
window.navigator.msSaveBlob(blob, filename);
} else {
var URL = window.URL || window.webkitURL;
var downloadUrl = URL.createObjectURL(blob);
if (filename) {
// use HTML5 a[download] attribute to specify filename
var a = document.createElement("a");
// safari doesn't support this yet
if (typeof a.download === 'undefined') {
window.location = downloadUrl;
} else {
a.href = downloadUrl;
a.download = filename;
document.body.appendChild(a);
a.click();
}
} else {
window.location = downloadUrl;
}
setTimeout(function() {
URL.revokeObjectURL(downloadUrl);
$("#loaderInvoice").addClass("d-none");
}, 100); // cleanup
}
}
};
xhr.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
xhr.send($.param(params));
});
This works for me. Make sure you return a File from your controller action with contentType as "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" and file name as e.g. "List.xlsx" which should be the same as in the AJAX success call. I have used ClosedXML NuGet package to generate the excel file.
$.ajax({
url: "Home/Export",
type: 'GET',
contentType: 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
xhrFields: { responseType: 'blob' },
success: function (data) {
var a = document.createElement('a');
var url = window.URL.createObjectURL(data);
a.href = url;
a.download = 'List.xlsx';
a.click();
window.URL.revokeObjectURL(url);
}
});
I am using Asp.Net WebForm and just I wanna to download a file from server side. There is a lot article but I cannot find just basic answer.
Now, I tried a basic way and got it.
That's my problem.
I have to create a lot of input button dynamically on runtime. And I want to add each button to download button with giving an unique fileNumber.
I create each button like this:
fragment += "<div><input type=\"button\" value=\"Create Excel\" onclick=\"CreateExcelFile(" + fileNumber + ");\" /></div>";
Each button call this ajax method.
$.ajax({
type: 'POST',
url: 'index.aspx/CreateExcelFile',
data: jsonData,
contentType: 'application/json; charset=utf-8',
dataType: 'json',
success: function (returnValue) {
window.location = '/Reports/Downloads/' + returnValue.d;
}
});
Then I wrote a basic simple method.
[WebMethod]
public static string CreateExcelFile2(string fileNumber)
{
string filePath = string.Format(#"Form_{0}.xlsx", fileNumber);
return filePath;
}
I am generating this Form_1, Form_2, Form_3.... And I am going to delete this old files with another program. But if there is a way to just sending byte array to download file like using Response. I wanna to use it.
I hope this will be usefull for anyone.
On Submit form
public ActionResult ExportXls()
{
var filePath="";
CommonHelper.WriteXls(filePath, "Text.xls");
}
public static void WriteXls(string filePath, string targetFileName)
{
if (!String.IsNullOrEmpty(filePath))
{
HttpResponse response = HttpContext.Current.Response;
response.Clear();
response.Charset = "utf-8";
response.ContentType = "text/xls";
response.AddHeader("content-disposition", string.Format("attachment; filename={0}", targetFileName));
response.BinaryWrite(File.ReadAllBytes(filePath));
response.End();
}
}