Solved

Winforms WebClient.UploadFile() error (System.NotSupportedException)

Posted on 2010-08-13
4
1,755 Views
Last Modified: 2013-11-26
I am simply trying to upload a file to a URL and the following error message is generated:

System.Net.WebException: An exception occurred during a WebClient request. ---> System.NotSupportedException: The stream does not support concurrent IO read or write operations.
   at System.Net.ConnectStream.InternalWrite(Boolean async, Byte[] buffer, Int32 offset, Int32 size, AsyncCallback callback, Object state)
   at System.Net.ConnectStream.Write(Byte[] buffer, Int32 offset, Int32 size)
   at System.Net.WebClient.UploadBitsState.WriteBytes()
   at System.Net.WebClient.UploadBits(WebRequest request, Stream readStream, Byte[] buffer, Byte[] header, Byte[] footer, CompletionDelegate completionDelegate, AsyncOperation asyncOp)
   at System.Net.WebClient.UploadFile(Uri address, String method, String fileName)
   --- End of inner exception stack trace ---
   at System.Net.WebClient.UploadFile(Uri address, String method, String fileName)
   at BREN_iTropics_001.frmUnifiedXML.simpleDataUpload() in frmUnifiedXML.cs:line 61

The offending line is:

byte[] Byte_response = wClient.UploadFile(url, "POST",filename);

can someone see the problem?
private void simpleDataUpload()
{
    try
    {
        Uri url = new Uri(this.txtFTPServer.Text);
        WebClient wClient = new WebClient();
        NetworkCredential nc = new NetworkCredential("login", "pass");
        wClient.Credentials = nc;
        byte[] Byte_response = wClient.UploadFile(url, "POST", filename);

        wClient.UploadProgressChanged += new UploadProgressChangedEventHandler(wClient_UploadProgressChanged);
        wClient.UploadFileCompleted += new UploadFileCompletedEventHandler(wClient_UploadFileCompleted);

        if (Byte_response != null)
        {
            this.txtMsg.Text += System.Text.Encoding.ASCII.GetString(Byte_response);
        }
    }
    catch (Exception ex)
    {
        this.txtMsg.Text += ex.ToString() + Environment.NewLine;
    }
}

void wClient_UploadProgressChanged(object sender, UploadProgressChangedEventArgs e)
{
    this.txtLastResult.Text = "Sent:" + e.BytesSent.ToString() + "  Total:"
                        + e.TotalBytesToSend.ToString() + "   Progress:"
                        + e.ProgressPercentage.ToString() + "%";
}

Open in new window

0
Comment
Question by:conrad2010
  • 2
4 Comments
 
LVL 7

Expert Comment

by:Gewgala
ID: 33434698
Are you sure you have correct credentials?
0
 
LVL 7

Expert Comment

by:Gewgala
ID: 33434701
And if you have correct credentials, are you sure you have sufficient privileges to perform your upload with them?
0
 
LVL 3

Accepted Solution

by:
bkokx earned 500 total points
ID: 33435351
Problem might be in your "POST" argument.
POST is used for HTTP while for FTP this should be STOR.
These defaults are chosen by the function if you do not specify the argument.
0
 

Author Comment

by:conrad2010
ID: 33438406
yes, the credentials are correct and I have permission to store (tested it in a browser upload version)

-C
0

Featured Post

DevOps Toolchain Recommendations

Read this Gartner Research Note and discover how your IT organization can automate and optimize DevOps processes using a toolchain architecture.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

A long time ago (May 2011), I have written an article showing you how to create a DLL using Visual Studio 2005 to be hosted in SQL Server 2005. That was valid at that time and it is still valid if you are still using these versions. You can still re…
The article shows the basic steps of integrating an HTML theme template into an ASP.NET MVC project
Two types of users will appreciate AOMEI Backupper Pro: 1 - Those with PCIe drives (and haven't found cloning software that works on them). 2 - Those who want a fast clone of their boot drive (no re-boots needed) and it can clone your drive wh…
Although Jacob Bernoulli (1654-1705) has been credited as the creator of "Binomial Distribution Table", Gottfried Leibniz (1646-1716) did his dissertation on the subject in 1666; Leibniz you may recall is the co-inventor of "Calculus" and beat Isaac…

791 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question