Solved

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

Posted on 2010-08-13
4
1,760 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
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 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

Independent Software Vendors: We Want Your Opinion

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

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

Suggested Solutions

Title # Comments Views Activity
Generate Unique ID in VB.NET 21 104
transition to visual .net from vb6 5 63
Updating a single record in forEach using C#/Entity 7 26
"The resource cannot be found" 1 24
It was really hard time for me to get the understanding of Delegates in C#. I went through many websites and articles but I found them very clumsy. After going through those sites, I noted down the points in a easy way so here I am sharing that unde…
This article aims to explain the working of CircularLogArchiver. This tool was designed to solve the buildup of log file in cases where systems do not support circular logging or where circular logging is not enabled
The Email Laundry PDF encryption service allows companies to send confidential encrypted  emails to anybody. The PDF document can also contain attachments that are embedded in the encrypted PDF. The password is randomly generated by The Email Laundr…

733 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