I am reading a file in bytes using ReadAllBytes() method. Then convert these bytes to base64. Then send this base64 string as a part of JSON. On server side (which is MVC action) I receive the JSON and convert the base64 into bytes and then save it.
Small files in KB are transferring very fast and saving in temp folder. But the files in MB is not transferring at all.
I have set maxrequestlength, execution timeout done every thing with web config and even test by using httpwebrequest.keepalive = true and false.... but still all in vain. I can't send file chunks because its not the requirement. Want to send a Complete file at once...
byte[] b = File.ReadAllBytes("D://test.pdf");
string convert = Convert.ToBase64String(b);
Customer cs = new Customer();
cs.JsonString = convert;
JavaScriptSerializer js = new JavaScriptSerializer();
js.MaxJsonLength = Int32.MaxValue;
string json = js.Serialize(cs);
var request (HttpWebRequest)WebRequest.Create("http://localhost:46360/Home/Tester");
request.Method = "POST";
request.ContentType = "application/json; charset=utf-8";
request.ContentLength = (json.Length);
request.KeepAlive = false;
request.Timeout = System.Threading.Timeout.Infinite;
request.Accept = "Accept=application/json";
request.SendChunked = false;
request.AllowWriteStreamBuffering = false;
using (var streamWriter = new StreamWriter(request.GetRequestStream()))
{
streamWriter.Write(json);
streamWriter.Close();
}
var response = (HttpWebResponse)request.GetResponse();
using (var streamReader = new StreamReader(response.GetResponseStream()))
{
var result = streamReader.ReadToEnd();
}
Related
So here in C# code i am sending corgi to client which has corgiBabies. Using ClosedXml here.
var wbCorgiBabiesTemplate = new XLWorkbook();
var wsCoriBabiesAmendementTemplate = wbCorgiBabiesTemplate.Worksheets.Add(" Work Sheet Corgi baby Template");
wsCoriBabiesAmendementTemplate.Cell("A1").Value = "Corgi Parent";
wsCoriBabiesAmendementTemplate.Cell("B1").Value = "Corgi Child";
wsCoriBabiesAmendementTemplate.Cell("A2").Value = "Petunia";
wsCoriBabiesAmendementTemplate.Cell("B2").Value = "Khaleesi";
using (var ms = new MemoryStream())
{
wbCorgiBabiesTemplate.SaveAs(ms);
byte[] Corgibabies = ms.ToArray();
}
corgi.Corgibabies = System.Text.Encoding.UTF8.GetString(Corgibabies);
return corgi;
After that in Client i want to open corgibabies in excel sheet but the conversion here is wrong somewhere i think that excel sheet doesn't open correctly.
var fileName = 'CorgiBabies.xlsx';
dataAccessService.get('corgi')
.then(function(response) {
let utf8Encode = new TextEncoder();
var strBytes = utf8Encode.encode(response.corgiBabies);
var a = document.createElement("a");
document.body.appendChild(a);
a.style = "display: none";
var file = new Blob([strBytes], {type: 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet'});
var fileURL = window.URL.createObjectURL(file);
a.href = fileURL;
a.download = fileName;
a.click();
})
Below what excel sheet gives me error in image
Assuming you're on .Net Core+ (otherwise you can find the System.Buffers Nuget package for .Net standard or framework), on server side try
using System.Buffers;
using System.Buffers.Text;
and insert
var outputBuffer = new Span<byte>();
var status = Base64.EncodeToUtf8(Corgibabies, outputBuffer, out var consumed, out var written);
// sanity check
// if (status != OperationStatus.Done) throw new Exception();`
// do the above just before replacing
// System.Text.Encoding.UTF8.GetString(Corgibabies);
// with
System.Text.Encoding.UTF8.GetString(outputBuffer);
Now I'm pretty certain that will ensure that the server responds with what the client should expect but I'm not set up to test the Javascript side of things (yet). In the meantime let me know if this helps you make progress.
PS1: the error in your original code was the implicit assumption that Corgibabies is an array containing the bytes of a UTF8 encoded string. It actually contains the raw bytes of what would normally be an .xlsx file on disk. What is needed is to make that into text (Base64 encoding) and ensure that text is UTF8. Obviously in the Javascript you need to do the reverse - UTF8 Base64 to binary, save to disk, open in Excel...
Instead of returning string as the Content, you can make it work with File.
public ActionResult Get()
{
var wbCorgiBabiesTemplate = new XLWorkbook();
var wsCoriBabiesAmendementTemplate = wbCorgiBabiesTemplate.Worksheets.Add(" Work Sheet Corgi baby Template");
wsCoriBabiesAmendementTemplate.Cell("A1").Value = "Corgi Parent";
wsCoriBabiesAmendementTemplate.Cell("B1").Value = "Corgi Child";
wsCoriBabiesAmendementTemplate.Cell("A2").Value = "Petunia";
wsCoriBabiesAmendementTemplate.Cell("B2").Value = "Khaleesi";
wbCorgiBabiesTemplate.SaveAs("new.xlsx");
var ms = new MemoryStream();
wbCorgiBabiesTemplate.SaveAs(ms);
ms.Position = 0;
var fileName = "CorgiBabies.xlsx";
return File(ms, "application/octet-stream", fileName);
}
Api call:
or
fetch('https://localhost:7135/api/downloadExcel')
.then(resp => resp.blob())
.then(blob => {
const url = window.URL.createObjectURL(blob);
const a = document.createElement('a');
a.style.display = 'none';
a.href = url;
// the filename you want
a.download = 'CorgiBabies.xlsx';
document.body.appendChild(a);
a.click();
window.URL.revokeObjectURL(url);
})
.catch(() => alert('oh no!'));
Ref: git
ClosedXML has several extensions that will help you acheive what you need :
ClosedXML.Extensions.AspNet
ClosedXML.Extensions.Mvc
ClosedXML.Extensions.WebApi
You can install the appropriate extension for your project, to help give you a fast access to download the workbook. You can also save the file on disk, and pass the file link (path) to JavaScript, and continue your work on the file from JavaScript.
if you need to know how you would let the user download the file from ASP.NET,
then you can do this :
Simple workbook :
C#: ASP.NET MVC
[HttpGet]
public ActionResult Download(string fileName)
{
// create workbook
var workbook = new XLWorkbook();
var sheet = workbook.Worksheets.Add("Worksheet 1");
sheet.Cell("A1").Value = "A1";
sheet.Cell("B1").Value = "B1";
sheet.Cell("A2").Value = "A2";
sheet.Cell("B2").Value = "B2";
// get workbook bytes
byte[] workbookBytes;
using (var memoryStream = new MemoryStream())
{
workbook.SaveAs(memoryStream);
workbookBytes = memoryStream.ToArray();
}
return File(workbookBytes, "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet", fileName);
}
C#: ASP.NET Web Forms
public void Export(HttpResponse response, string fileName)
{
// create workbook
var workbook = new XLWorkbook();
var sheet = workbook.Worksheets.Add("Worksheet 1");
sheet.Cell("A1").Value = "A1";
sheet.Cell("B1").Value = "B1";
sheet.Cell("A2").Value = "A2";
sheet.Cell("B2").Value = "B2";
HttpResponse httpResponse = response;
httpResponse.Clear();
httpResponse.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
httpResponse.AddHeader("content-disposition", $"attachment;filename=\"{fileName}.xlsx\"");
using (var memoryStream = new MemoryStream())
{
workbook.SaveAs(memoryStream);
memoryStream.WriteTo(httpResponse.OutputStream);
}
httpResponse.End();
}
the above examples will directly download the file into the client device. However, if you want to pass the workbook bytes to the JavaScript, you will need to convert it to base64 string and pass it to the JavaScript like so :
var base64String = Convert.ToBase64String(workbookBytes);
Then from JavaScript decode it to Uint8Array :
/*
JavaScript
*/
// get base64 string array and decoded it
var data = atob(serverSideResult);
var array = new Array(data.length);
for (var i = 0; i < data.length; i++) {
array[i] = data.charCodeAt(i);
}
// final result
var dataUint8Array = new Uint8Array(array);
now you can work with dataUint8Array as normal Uint8Array.
if you want to pass it back to the server-side, you can convert the array to base64 string, and pass it to the server-side like so :
/*
JavaScript
*/
let binaryString = ''
for (var i = 0; i < dataUint8Array.byteLength; i++) {
binaryString += String.fromCharCode(dataUint8Array[i]);
}
//pass base64Result to the server-side (C#)
var base64Result = window.btoa(binaryString);
then from C# you just need to convert it back to array from base64 string like so :
var bytes = Convert.FromBase64String(dataReceivedFromJavaScript);
where bytes would be byte[].
I am trying to send a audio recording to server and save it as .wav. I am using angular on the front end and .net core on server. I was able to record, then make a blob of type "audio/wav". For sending it to server, I convert it into an array buffer and then the array buffer to base64 string which I post to controller.
On the server side when I write those bytes(after extracting array buffer from base 64), to a wav file, I cant play it. Can someone help me what I am doing wrong on the .net controller side.
If someone knows a cleaner way of doing this, please let me know
You don't have to create an array buffer. Just use a file-input and send form-data.
Assuming you are on angular 4.3++ and using HttpClientModule from #angular/common/http:
The angular-service method
public uploadFile(file: File): Observable<any> {
const formData = new FormData();
formData.Append('myFile', file);
return this.http.post('my-api-url', formData);
}
now you asp.net-core endpoint
[HttpPost]
// attention name of formfile must be equal to the key u have used for formdata
public async Task<IActionResult> UploadFileAsync([FromForm] IFormFile myFile)
{
var totalSize = myFile.Length;
var fileBytes = new byte[myFile.Length];
using (var fileStream = myFile.OpenReadStream())
{
var offset = 0;
while (offset < myFile.Length)
{
var chunkSize = totalSize - offset < 8192 ? (int) totalSize - offset : 8192;
offset += await fileStream.ReadAsync(fileBytes, offset, chunkSize);
}
}
// now save the file on the filesystem
StoreFileBytes("mypath", fileBytes);
return Ok();
}
I have a pdf file which is generated into my local server with my server side code. I want to send a request to the another server requesting POST. The post method take parameter as FormData where formdata types
one is string and another is file type.
content-type
form-data
Body
PDF file (file type)
string value
Is it possible to make the POST request without browsing the file location?
Doing some R&D I have overcome this problem with following some steps, as there is no way to get the file object from the physical location automatically in client side (basically in js) except browsing for security reason.
In my local server I have created a REST service. which response base64 string of the desired file.
Than I call the REST api from my javaScript and as a response I receive the base64 string. And than I convert it into bytes array and than Blob object and than File object.
base64 string==>bytes array==>Blob object==>File object
var base64 = this.getpdfFromLocal() //get the base64 string
var byteArray= this.base64ToByte(base64 );
var file = this.getFileFromByteArray(byteArray);
//return the byte array form the base64 string
MyApi.prototype.base64ToByte= function(base64) {
var binaryString = window.atob(base64);
var binaryLen = binaryString.length;
var bytes = new Uint8Array(binaryLen);
for (var i = 0; i < binaryLen; i++) {
var ascii = binaryString.charCodeAt(i);
bytes[i] = ascii;
}
return bytes;
};
MyApi.prototype.getFileFromByteArray=function(byteArray) {
var blob = new Blob([byteArray]);
var file = new File([blob], "resource.pdf");
return file;
};
Lastly I make from data using file object and send request the another server REST web services.
var formdata = new FormData();
formdata.append("some_value", "Some String");
formdata.append("file", file);
var url = "http://yoururl.com";
var result =$.ajax({
url : url ,
type : 'POST',
data : formdata,
contentType : false,
cache : false,
processData : false,
scriptCharset : 'utf-8',
async : false
}).responseText;
I am working on a solution where i need to generate preview in popup for (pdf,word,excel) .I have achieved same by converting all format using Aspose.Words and Aspose.Cells. Below is my code:
public ActionResult PreviewDoc(string fileName)
{
string fileExtension = fileName.Substring(fileName.LastIndexOf(".") + 1);
string pathSource = Server.MapPath("~/"+ fileName);
MemoryStream streamToWrite = new MemoryStream();
using (FileStream file = new FileStream(pathSource, FileMode.Open, FileAccess.Read))
{
byte[] bytes = new byte[file.Length];
file.Read(bytes, 0, (int)file.Length);
streamToWrite.Write(bytes, 0, (int)file.Length);
}
var previewStream = this.GetPdfStream(fileExtension, streamToWrite);
// Load the document.
// Convert the document to byte form.
byte[] docBytes = previewStream.ToArray();
// The bytes are now ready to be stored/transmitted.
// Now reverse the steps to load the bytes back into a document object.
MemoryStream inStream = new MemoryStream();
inStream.Write(docBytes, 0, docBytes.Length);
inStream.Position = 0;
return new FileStreamResult(inStream, "application/pdf");
}
public MemoryStream GetPdfStream(string extension, MemoryStream streamToRead)
{
MemoryStream outStream = new MemoryStream();
if (extension.Trim().ToLower() == "doc" || extension.Trim().ToLower() == "docx")
{
Aspose.Words.Document doc = new Aspose.Words.Document(streamToRead);
// Save the document to stream.
doc.Save(outStream, SaveFormat.Pdf);
}
else if (extension.Trim().ToLower() == "xls" || extension.Trim().ToLower() == "xlsx")
{
Aspose.Cells.Workbook workbook = new Aspose.Cells.Workbook(streamToRead);
workbook.Save(outStream, Aspose.Cells.SaveFormat.Pdf);
}
else
{
outStream = streamToRead;
}
return outStream;
}
But as Aspose requires licesnse which i don't have so do we have any client side approach where we return stream from mvc controller and convert that to preview at client side and open in new window?
Yes it is true that a valid license is a must to achieve the task. You can convert and send the output stream to client browser but it will contain the Aspose watermark. Furthermore you can get a temporary license for evaluation. Please visit the link and get the temporary license for 30 days.
I work with Aspose as Developer evangelist.
I have generated a Pdf on the server, and need to return it as a response to my web client, so that I get a 'Save As' dialog.
The pdf is generated, and saved to a Memory stream... which is then returned to my method which will return the HttpResponseMessage.
The is the method:
[Route("GeneratePdf"), HttpPost]
public HttpResponseMessage GeneratePdf(PlateTemplateExtendedDto data)
{
var doc = GeneratePdf(DataForThePdf);
//using (var file = File.OpenWrite("c:\\temp\\test.pdf"))
// doc.CopyTo(file); // no need for manual stream copy and buffers
HttpResponseMessage response = Request.CreateResponse(HttpStatusCode.OK);
byte[] buffer = new byte[0];
//get buffer
buffer = doc.GetBuffer();
//content length for use in header
var contentLength = buffer.Length;
response.Headers.AcceptRanges.Add("bytes");
response.StatusCode = HttpStatusCode.OK;
response.Content = new StreamContent(doc);
response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("render");
response.Content.Headers.ContentDisposition.FileName = "yes.pdf";
response.Content.Headers.ContentType = new MediaTypeHeaderValue("application/pdf");
response.Content.Headers.ContentLength = doc.Length;
return response;
}
However, the document renders as a blank file, and although it has a file size, and properties of the document I created (pdf information if File Properties is all right, as well as page width and height), the document displays as blank.
If I un-comment the code that is commented out, to save locally, the file is perfect. File size is 228,889 bytes. However, when I let it go to my web page and save it, it's 405,153 bytes and the filename is 'undefined'.
If I breakpoint, I see these results:
On the front end script, I handle the downloaded object like this:
$.post("/api/PlateTemplate/GeneratePdf", data).done(function (data, status, headers) {
// headers = headers();
var filename = headers['x-filename'];
var contentType = headers['content-type'];
//Create a url to the blob
var blob = new Blob([data], { type: contentType });
var url = window.URL.createObjectURL(blob);
var linkElement = document.createElement('a');
linkElement.setAttribute('href', url);
linkElement.setAttribute("download", filename);
//Force a download
var clickEvent = new MouseEvent("click", {
"view": window,
"bubbles": true,
"cancelable": false
});
linkElement.dispatchEvent(clickEvent);
});
I'm unsure where the file is being corrupted. What am I doing wrong?
Edit: Using the following code as suggested:
$.post("/api/PlateTemplate/GeneratePdf", data).done(function (data, status, headers) {
alert(data.length);
var xhr = new XMLHttpRequest();
$("#pdfviewer").attr("src", URL.createObjectURL(new Blob([data], {
type: "application/pdf"
})))
.Net code:
var doc = GeneratePdf(pdfParams);
HttpResponseMessage response = Request.CreateResponse(HttpStatusCode.OK);
byte[] buffer = new byte[0];
//get buffer
buffer = doc.ToArray();
//content length for use in header
var contentLength = buffer.Length;
response.Headers.AcceptRanges.Add("bytes");
response.StatusCode = HttpStatusCode.OK;
response.Content = new StreamContent(doc);
response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("render");
response.Content.Headers.ContentDisposition.FileName = "yes.pdf";
response.Content.Headers.ContentType = new MediaTypeHeaderValue("application/pdf");
response.Content.Headers.ContentLength = doc.Length;
return response;
It seems I am losing data.
The alert is the length of the 'data.length' in my javascript, after I get data back from the call.
The file properties is the original pdf file info.
File sends from api, size is 227,564, which matches the byte size on disk if I save it. So it SEEMS the sending is OK. But on the javascript size, when I read in the file, it's 424946, when I do: var file = new Blob([data], { type: 'application/pdf' }); (Where data is the response from the server).
The ContentLength setting looks somewhat suspicious (not consequent):
//content length for use in header
var contentLength = buffer.Length;
response.Content.Headers.ContentLength = doc.Length;
I 'fixed' this by using base64 encoded string from the .Net controller to the javascript web api call result, and then allowed the browser to convert it into binary by specifying the type ('application/pdf').