Develop Reference

How to implement WebClient.UploadFileAsync with HttpClient? [duplicate]

Does anyone know how to use the HttpClient in .Net 4.5 with multipart/form-data upload?
I couldn't find any examples on the internet.

my result looks like this:
public static async Task<string> Upload(byte[] image)
{
using (var client = new HttpClient())
{
using (var content =
new MultipartFormDataContent("Upload----" + DateTime.Now.ToString(CultureInfo.InvariantCulture)))
{
content.Add(new StreamContent(new MemoryStream(image)), "bilddatei", "upload.jpg");
using (
var message =
await client.PostAsync("http://www.directupload.net/index.php?mode=upload", content))
{
var input = await message.Content.ReadAsStringAsync();
return !string.IsNullOrWhiteSpace(input) ? Regex.Match(input, #"http://\w*\.directupload\.net/images/\d*/\w*\.[a-z]{3}").Value : null;
}
}
}
}

It works more or less like this (example using an image/jpg file):
async public Task<HttpResponseMessage> UploadImage(string url, byte[] ImageData)
{
var requestContent = new MultipartFormDataContent();
// here you can specify boundary if you need---^
var imageContent = new ByteArrayContent(ImageData);
imageContent.Headers.ContentType =
MediaTypeHeaderValue.Parse("image/jpeg");
requestContent.Add(imageContent, "image", "image.jpg");
return await client.PostAsync(url, requestContent);
}
(You can requestContent.Add() whatever you want, take a look at the HttpContent descendant to see available types to pass in)
When completed, you'll find the response content inside HttpResponseMessage.Content that you can consume with HttpContent.ReadAs*Async.

This is an example of how to post string and file stream with HTTPClient using MultipartFormDataContent. The Content-Disposition and Content-Type need to be specified for each HTTPContent:
Here's my example. Hope it helps:
private static void Upload()
{
using (var client = new HttpClient())
{
client.DefaultRequestHeaders.Add("User-Agent", "CBS Brightcove API Service");
using (var content = new MultipartFormDataContent())
{
var path = #"C:\B2BAssetRoot\files\596086\596086.1.mp4";
string assetName = Path.GetFileName(path);
var request = new HTTPBrightCoveRequest()
{
Method = "create_video",
Parameters = new Params()
{
CreateMultipleRenditions = "true",
EncodeTo = EncodeTo.Mp4.ToString().ToUpper(),
Token = "x8sLalfXacgn-4CzhTBm7uaCxVAPjvKqTf1oXpwLVYYoCkejZUsYtg..",
Video = new Video()
{
Name = assetName,
ReferenceId = Guid.NewGuid().ToString(),
ShortDescription = assetName
}
}
};
//Content-Disposition: form-data; name="json"
var stringContent = new StringContent(JsonConvert.SerializeObject(request));
stringContent.Headers.Add("Content-Disposition", "form-data; name=\"json\"");
content.Add(stringContent, "json");
FileStream fs = File.OpenRead(path);
var streamContent = new StreamContent(fs);
streamContent.Headers.Add("Content-Type", "application/octet-stream");
//Content-Disposition: form-data; name="file"; filename="C:\B2BAssetRoot\files\596090\596090.1.mp4";
streamContent.Headers.Add("Content-Disposition", "form-data; name=\"file\"; filename=\"" + Path.GetFileName(path) + "\"");
content.Add(streamContent, "file", Path.GetFileName(path));
//content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment");
Task<HttpResponseMessage> message = client.PostAsync("http://api.brightcove.com/services/post", content);
var input = message.Result.Content.ReadAsStringAsync();
Console.WriteLine(input.Result);
Console.Read();
}
}
}

Try this its working for me.
private static async Task<object> Upload(string actionUrl)
{
Image newImage = Image.FromFile(#"Absolute Path of image");
ImageConverter _imageConverter = new ImageConverter();
byte[] paramFileStream= (byte[])_imageConverter.ConvertTo(newImage, typeof(byte[]));
var formContent = new MultipartFormDataContent
{
// Send form text values here
{new StringContent("value1"),"key1"},
{new StringContent("value2"),"key2" },
// Send Image Here
{new StreamContent(new MemoryStream(paramFileStream)),"imagekey","filename.jpg"}
};
var myHttpClient = new HttpClient();
var response = await myHttpClient.PostAsync(actionUrl.ToString(), formContent);
string stringContent = await response.Content.ReadAsStringAsync();
return response;
}

Here is another example on how to use HttpClient to upload a multipart/form-data.
It uploads a file to a REST API and includes the file itself (e.g. a JPG) and additional API parameters. The file is directly uploaded from local disk via FileStream.
See here for the full example including additional API specific logic.
public static async Task UploadFileAsync(string token, string path, string channels)
{
// we need to send a request with multipart/form-data
var multiForm = new MultipartFormDataContent();
// add API method parameters
multiForm.Add(new StringContent(token), "token");
multiForm.Add(new StringContent(channels), "channels");
// add file and directly upload it
FileStream fs = File.OpenRead(path);
multiForm.Add(new StreamContent(fs), "file", Path.GetFileName(path));
// send request to API
var url = "https://slack.com/api/files.upload";
var response = await client.PostAsync(url, multiForm);
}

Here's a complete sample that worked for me. The boundary value in the request is added automatically by .NET.
var url = "http://localhost/api/v1/yourendpointhere";
var filePath = #"C:\path\to\image.jpg";
HttpClient httpClient = new HttpClient();
MultipartFormDataContent form = new MultipartFormDataContent();
FileStream fs = File.OpenRead(filePath);
var streamContent = new StreamContent(fs);
var imageContent = new ByteArrayContent(streamContent.ReadAsByteArrayAsync().Result);
imageContent.Headers.ContentType = MediaTypeHeaderValue.Parse("multipart/form-data");
form.Add(imageContent, "image", Path.GetFileName(filePath));
var response = httpClient.PostAsync(url, form).Result;

Example with preloader Dotnet 3.0 Core
ProgressMessageHandler processMessageHander = new ProgressMessageHandler();
processMessageHander.HttpSendProgress += (s, e) =>
{
if (e.ProgressPercentage > 0)
{
ProgressPercentage = e.ProgressPercentage;
TotalBytes = e.TotalBytes;
progressAction?.Invoke(progressFile);
}
};
using (var client = HttpClientFactory.Create(processMessageHander))
{
var uri = new Uri(transfer.BackEndUrl);
client.DefaultRequestHeaders.Authorization =
new AuthenticationHeaderValue("Bearer", AccessToken);
using (MultipartFormDataContent multiForm = new MultipartFormDataContent())
{
multiForm.Add(new StringContent(FileId), "FileId");
multiForm.Add(new StringContent(FileName), "FileName");
string hash = "";
using (MD5 md5Hash = MD5.Create())
{
var sb = new StringBuilder();
foreach (var data in md5Hash.ComputeHash(File.ReadAllBytes(FullName)))
{
sb.Append(data.ToString("x2"));
}
hash = result.ToString();
}
multiForm.Add(new StringContent(hash), "Hash");
using (FileStream fs = File.OpenRead(FullName))
{
multiForm.Add(new StreamContent(fs), "file", Path.GetFileName(FullName));
var response = await client.PostAsync(uri, multiForm);
progressFile.Message = response.ToString();
if (response.IsSuccessStatusCode) {
progressAction?.Invoke(progressFile);
} else {
progressErrorAction?.Invoke(progressFile);
}
response.EnsureSuccessStatusCode();
}
}
}

I'm adding a code snippet which shows on how to post a file to an API which has been exposed over DELETE http verb. This is not a common case to upload a file with DELETE http verb but it is allowed. I've assumed Windows NTLM authentication for authorizing the call.
The problem that one might face is that all the overloads of HttpClient.DeleteAsync method have no parameters for HttpContent the way we get it in PostAsync method
var requestUri = new Uri("http://UrlOfTheApi");
using (var streamToPost = new MemoryStream("C:\temp.txt"))
using (var fileStreamContent = new StreamContent(streamToPost))
using (var httpClientHandler = new HttpClientHandler() { UseDefaultCredentials = true })
using (var httpClient = new HttpClient(httpClientHandler, true))
using (var requestMessage = new HttpRequestMessage(HttpMethod.Delete, requestUri))
using (var formDataContent = new MultipartFormDataContent())
{
formDataContent.Add(fileStreamContent, "myFile", "temp.txt");
requestMessage.Content = formDataContent;
var response = httpClient.SendAsync(requestMessage).GetAwaiter().GetResult();
if (response.IsSuccessStatusCode)
{
// File upload was successfull
}
else
{
var erroResult = response.Content.ReadAsStringAsync().GetAwaiter().GetResult();
throw new Exception("Error on the server : " + erroResult);
}
}
You need below namespaces at the top of your C# file:
using System;
using System.Net;
using System.IO;
using System.Net.Http;
P.S. You are seeing a number of using blocks(IDisposable pattern) in the above code snippet which doesn't look very clean. Unfortunately, the syntax of using construct doesn't support initializing multiple variables in single statement.

X509Certificate clientKey1 = null;
clientKey1 = new X509Certificate(AppSetting["certificatePath"],
AppSetting["pswd"]);
string url = "https://EndPointAddress";
FileStream fs = File.OpenRead(FilePath);
var streamContent = new StreamContent(fs);
var FileContent = new ByteArrayContent(streamContent.ReadAsByteArrayAsync().Result);
FileContent.Headers.ContentType = MediaTypeHeaderValue.Parse("ContentType");
var handler = new WebRequestHandler();
handler.ClientCertificateOptions = ClientCertificateOption.Manual;
handler.ClientCertificates.Add(clientKey1);
handler.ServerCertificateValidationCallback = (httpRequestMessage, cert, cetChain, policyErrors) =>
{
return true;
};
using (var client = new HttpClient(handler))
{
// Post it
HttpResponseMessage httpResponseMessage = client.PostAsync(url, FileContent).Result;
if (!httpResponseMessage.IsSuccessStatusCode)
{
string ss = httpResponseMessage.StatusCode.ToString();
}
}

public async Task<object> PassImageWithText(IFormFile files)
{
byte[] data;
string result = "";
ByteArrayContent bytes;
MultipartFormDataContent multiForm = new MultipartFormDataContent();
try
{
using (var client = new HttpClient())
{
using (var br = new BinaryReader(files.OpenReadStream()))
{
data = br.ReadBytes((int)files.OpenReadStream().Length);
}
bytes = new ByteArrayContent(data);
multiForm.Add(bytes, "files", files.FileName);
multiForm.Add(new StringContent("value1"), "key1");
multiForm.Add(new StringContent("value2"), "key2");
var res = await client.PostAsync(_MEDIA_ADD_IMG_URL, multiForm);
}
}
catch (Exception e)
{
throw new Exception(e.ToString());
}
return result;
}

Upload files in chunks - .Net core

Need help on uploading a file in chunks in .Net core.
I got a stream of 1GB data, need to split in 64MB chucks and post to an API.
I got the below implementation of posting stream of data in single POST request, need suggestion on splitting the stream and POST in multiple API call
private async Task<string> Publish(string siteId, string datasourceName, string projectId, SkyConnection connectionInfo, MemoryStream file, string fileName)
{
_authInfo = await GetAccessToken(siteId);
var datasourceId = string.Empty;
var boundaryId = Guid.NewGuid().ToString();
using (var multipartcontent = new MultipartContent("mixed", boundaryId))
{
var stringContent = new StringContent(GetPublishRequest(datasourceName, projectId, connectionInfo));
stringContent.Headers.Remove("Content-Type");
stringContent.Headers.Remove("Content-Disposition");
stringContent.Headers.TryAddWithoutValidation("Content-Disposition", "name=\"request_payload\"");
stringContent.Headers.TryAddWithoutValidation("Content-Type", "text/xml");
multipartcontent.Add(stringContent);
file.Position = 0;
var streamContent = new StreamContent(file);
streamContent.Headers.TryAddWithoutValidation("Content-Disposition", $"name=\"tableau_datasource\"; filename=\"{fileName}\"");
streamContent.Headers.TryAddWithoutValidation("Content-Type", "application/octet-stream");
multipartcontent.Add(streamContent);
var req = new HttpRequestMessage(HttpMethod.Post, GetUrl($"sites/{_authInfo.SiteId}/datasources?datasourceType=tdsx"));
req.Content = multipartcontent;
req.Headers.Add("X-Tableau-Auth", _authInfo.Token);
req.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
var res = await _httpHandler.SendAsync(req);
res.EnsureSuccessStatusCode();
var joResponse = JObject.Parse(await res.Content.ReadAsStringAsync());
datasourceId = joResponse["datasource"]["id"].ToString();
}
return datasourceId;
}

Http client Post with body parameter and file in c#

I was trying to attach a csv file as a body parameter in my test script. But still as per the below code controller expect file and just curious how should I pass that.
I run test script in below order
Method-1
public void AttachedRatesFile(string fileName)
{
_form = string.IsNullOrWhiteSpace(fileName)
? _form = new StringContent(string.Empty)
: _form = new StreamContent(File.OpenRead($"{ResourceFolder}{fileName}"));
_form.Headers.ContentType = new MediaTypeHeaderValue("application/csv");
_form.Headers.ContentDisposition = new ContentDispositionHeaderValue(fileName);
}
Method-2
public void PostRequestExecutes(string resource)
{
var content = new MultipartFormDataContent{_form};
WhenThePostRequestExecutesWithContent(resource, content);
}
Method-3
public async void WhenThePostRequestExecutesWithContent(string resource, HttpContent content)
{
ResponseMessage = await HttpClient.PostAsync(resource, content);
}
I see null in below file parameter
Controller:
public async Task<IActionResult> SeedData(IFormFile file)
{
var result = await _seedDataService.SeedData(file);
return Ok(new { IsUploadSuccesful = result});
}

I would add that to the body as a stream
var memoryContentStream = new MemoryStream();
using (var streamWriter = new StreamWriter(memoryContentStream, Encoding.UTF8, 1000,
true))
{
using (var jsonTextWriter = new JsonTextWriter(streamWriter))
{
var jsonSerializer = new JsonSerializer();
jsonSerializer.Serialize(jsonTextWriter, OBJECT);
jsonTextWriter.Flush();
}
}
if (memoryContentStream.CanSeek)
{
memoryContentStream.Seek(0, SeekOrigin.Begin);
}
Then
using (var streamContent = new StreamContent(memoryContentStream))
{
streamContent.Headers.ContentType = new MediaTypeHeaderValue("application/json");
request.Content = streamContent;
using (var response = await _httpClient.SendAsync(request, HttpCompletionOption.ResponseHeadersRead))
{
var stream = await response.Content.ReadAsStreamAsync();
response.EnsureIsSuccessStatusCode();
}
}
The above would first write the content as a memory stream and then when creating the POST request you can send the stream as a streamContent

How to post form-data IFormFile with HttpClient?

I have backend endpoint Task<ActionResult> Post(IFormFile csvFile) and I need to call this endpoint from HttpClient. Currently I am getting Unsupported media type error.
Here is my code:
var filePath = Path.Combine("IntegrationTests", "file.csv");
var gg = File.ReadAllBytes(filePath);
var byteArrayContent = new ByteArrayContent(gg);
var postResponse = await _client.PostAsync("offers", new MultipartFormDataContent
{
{byteArrayContent }
});

You need to specify parameter name in MultipartFormDataContent collection matching action parameter name (csvFile) and a random file name
var multipartContent = new MultipartFormDataContent();
multipartContent.Add(byteArrayContent, "csvFile", "filename");
var postResponse = await _client.PostAsync("offers", multipartContent);
or equivalent
var postResponse = await _client.PostAsync("offers", new MultipartFormDataContent {
{ byteArrayContent, "csvFile", "filename" }
});

Use this snippet:
const string url = "https://localhost:5001/api/Upload";
const string filePath = #"C:\Path\To\File.png";
using (var httpClient = new HttpClient())
{
using (var form = new MultipartFormDataContent())
{
using (var fs = File.OpenRead(filePath))
{
using (var streamContent = new StreamContent(fs))
{
using (var fileContent = new ByteArrayContent(await streamContent.ReadAsByteArrayAsync()))
{
fileContent.Headers.ContentType = MediaTypeHeaderValue.Parse("multipart/form-data");
// "file" parameter name should be the same as the server side input parameter name
form.Add(fileContent, "file", Path.GetFileName(filePath));
HttpResponseMessage response = await httpClient.PostAsync(url, form);
}
}
}
}
}

This worked for me as a generic
public static Task<HttpResponseMessage> PostFormDataAsync<T>(this HttpClient httpClient, string url, string token, T data)
{
var content = new MultipartFormDataContent();
foreach (var prop in data.GetType().GetProperties())
{
var value = prop.GetValue(data);
if (value is FormFile)
{
var file = value as FormFile;
content.Add(new StreamContent(file.OpenReadStream()), prop.Name, file.FileName);
content.Headers.ContentDisposition = new ContentDispositionHeaderValue("form-data") { Name = prop.Name, FileName = file.FileName };
}
else
{
content.Add(new StringContent(JsonConvert.SerializeObject(value)), prop.Name);
}
}
if (!string.IsNullOrWhiteSpace(token))
httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
return httpClient.PostAsync(url, content);
}

Solved by using this code:
const string fileName = "csvFile.csv";
var filePath = Path.Combine("IntegrationTests", fileName);
var bytes = File.ReadAllBytes(filePath);
var form = new MultipartFormDataContent();
var content = new StreamContent(new MemoryStream(bytes));
form.Add(content, "csvFile");
content.Headers.ContentDisposition = new ContentDispositionHeaderValue("form-data")
{
Name = "csvFile",
FileName = fileName
};
content.Headers.Remove("Content-Type");
content.Headers.Add("Content-Type", "application/octet-stream; boundary=----WebKitFormBoundaryMRxYYlVt8KWT8TU3");
form.Add(content);
//Act
var postResponse = await _sellerClient.PostAsync("items/upload", form);

Post the attachment as an MultipartFormDataContent
var type = typeof(Startup);
var stream = type.Assembly.GetManifestResourceStream(type, "Resources.New.docx");
var fileContent = new StreamContent(stream);
var data = new MultipartFormDataContent
{
{ fileContent, "file", "New.docx" }
};
var response = await _client.PostAsync("upload", multipartContent);
Source: https://medium.com/#woeterman_94/c-webapi-upload-files-to-a-controller-e5ccf288b0ca

Please see the following working code with .NET 5.0 Environment.
You send the file as a byte[] and receive it as a IFormFile in the API.
//api controller receiver
[HttpPost("SendBackupFiles")]
public IActionResult SendBackupFiles(IFormFile file)
{
var filePath = Path.GetTempFileName();
using (var stream = System.IO.File.Create(filePath))
file.CopyToAsync(stream);
}
//client code sender example, not optimized lol.
const string filePath = #"C:\temp\hallo.csv";
using (var httpClient = new HttpClient())
{
var form = new MultipartFormDataContent();
byte[] fileData = File.ReadAllBytes(filePath);
ByteArrayContent byteContent = new ByteArrayContent(fileData);
byteContent.Headers.ContentType = MediaTypeHeaderValue.Parse("multipart/form-data");
form.Add(byteContent, "file", Path.GetFileName(filePath));
var result = httpClient.PostAsync("http://localhost:5070/..yourControllerName.../SendBackupFiles", form).ConfigureAwait(false).GetAwaiter().GetResult().Content.ReadAsStringAsync().Result;
}

Windows store get download progress

After struggling for a long time i finally got a code for downloading a file with using authentication and sending a header with a range in a windows store application , now the next level is to get a progress bar of the download , so any idea of the classes and methods that should be used for getting the download operation?
This is my code:
var httpClientHandler = new HttpClientHandler();
httpClientHandler.Credentials = new System.Net.NetworkCredential("", "");
var client = new HttpClient(httpClientHandler);
System.Net.Http.HttpRequestMessage request = new System.Net.Http.HttpRequestMessage(HttpMethod.Post, new Uri(""));
request.Headers.Range = new RangeHeaderValue(0,null);
HttpResponseMessage response = await client.SendAsync(request);
Stream stream = await response.Content.ReadAsStreamAsync();
StorageFile file = await folder.CreateFileAsync(fileName, CreationCollisionOption.GenerateUniqueName);
await Windows.Storage.FileIO.WriteBytesAsync(file, ReadStream(stream));

This task will be easier if you switch from System.Net.Http.HttpClient to Windows.Web.Http.HttpClient.
using Windows.Web.Http;
using Windows.Web.Http.Filters;
private async void Foo(StorageFolder folder, string fileName)
{
Uri uri = new Uri("http://localhost");
var filter = new HttpBaseProtocolFilter();
filter.ServerCredential =
new Windows.Security.Credentials.PasswordCredential(uri.ToString(), "foo", "bar");
var client = new HttpClient(filter);
HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Post, uri);
request.Headers.Add("Range", "bytes=0-");
// Hook up progress handler.
Progress<HttpProgress> progressCallback = new Progress<HttpProgress>(OnSendRequestProgress);
var tokenSource = new CancellationTokenSource();
HttpResponseMessage response = await client.SendRequestAsync(request).AsTask(tokenSource.Token, progressCallback);
IInputStream inputStream = await response.Content.ReadAsInputStreamAsync();
StorageFile file = await folder.CreateFileAsync(fileName, CreationCollisionOption.GenerateUniqueName);
// Copy from stream to stream.
IOutputStream outputStream = await file.OpenAsync(FileAccessMode.ReadWrite);
await RandomAccessStream.CopyAndCloseAsync(inputStream, outputStream);
}
private void OnSendRequestProgress(HttpProgress obj)
{
Debug.WriteLine(obj);
}
Otherwise, take a look at this other answer.