Windows form and WEB API

[Milanesi Stefano]

Helo,

I'm developing a windows form application (c#) that calls WEB API services (developed by me) and in particular I'm trying to "downloading" an Excel file (report) that it was previously created in a server folder ("Stampe").

I'm in trouble to "manage" client side, the response (HttpResponseMessage) from WEB API service.

• SERVER side:

[HttpGet]
public HttpResponseMessage GetFile(string FilePath, string FileName)
{
return GetFileStampa(FilePath, FileName);
}

public HttpResponseMessage GetFileStampa(string FilePath, string fileName)
{
var path = Path.Combine(FilePath, fileName);

var response = new HttpResponseMessage(HttpStatusCode.OK);

var stream = new FileStream(path, FileMode.Open);
response.Content = new StreamContent(stream);

response.Content.Headers.ContentType =
new MediaTypeHeaderValue("application/octet-stream");
response.Content.Headers.ContentDisposition =
new ContentDispositionHeaderValue("attachment");
response.Content.Headers.ContentDisposition.FileName = fileName;

return response;
}

• CLIENT side (windows form):

string FilePath = @"........\Stampe\";
string FileName = @"Test.xlsx";

string UrlGetFile = Url + "/File?" + "FilePath=" + FilePath + "&FileName=" + FileName;
Uri UriGetFile = new Uri(UrlGetFile);
HttpWebRequest request = WebRequest.Create(UriGetFile) as HttpWebRequest;
request.Method = "GET";
request.ContentType = "text/xml";
string results = string.Empty;
HttpWebResponse response;
using (response = request.GetResponse() as HttpWebResponse)
{
Stream objStream = response.GetResponseStream();
BinaryReader breader = new BinaryReader(objStream);
byte[] data = breader.ReadBytes((int)response.ContentLength);
File.WriteAllBytes("d:\\temp\\MyTest.xlsx", data);
}


the instruction "response.ContentLength" is always to -1. Message error: Non-negative number required

Where am I doing wrong (client or server side)?

Best

Stefano

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