I am writing a program that will submit a XML to a website. The code written works fine, but sometimes it just stops working for some reason, throwing a System.Net.ProtocolViolationException. I can close the program and re-run - it starts working again just fine.
Here is the code that I am using:
private string Summit(string xml)
{
string result = string.Empty;
StringBuilder sb = new StringBuilder();
try {
WebRequest request = WebRequest.Create(this.targetUrl);
request.Timeout = 800 * 1000;
RequestState requestState = new RequestState(xml);
requestState.Request = request;
request.ContentType = "text/xml";
// Set the 'Method' property to 'POST' to post data to a Uri.
requestState.Request.Method = "POST";
requestState.Request.ContentType = "text/xml";
// Start the Asynchronous 'BeginGetRequestStream' method call.
IAsyncResult r = (IAsyncResult)request.BeginGetRequestStream(new AsyncCallback(ReadCallBack), requestState);
// Pause the current thread until the async operation completes.
// Console.WriteLine("main thread waiting...");
allDone.WaitOne();
// Assign the response object of 'WebRequest' to a 'WebResponse' variable.
WebResponse response = null;
try {
response =request.GetResponse();
} catch (System.Net.ProtocolViolationException ex) {
response = null;
request.Abort();
request = null;
requestState = null;
return "";
}
//Console.WriteLine("The string has been posted.");
//Console.WriteLine("Please wait for the response...");
Stream streamResponse = response.GetResponseStream();
StreamReader streamRead = new StreamReader(streamResponse);
Char[] readBuff = new Char[256];
int count = streamRead.Read(readBuff, 0, 256);
//StringBuilder sb = new StringBuilder();
while (count > 0) {
String outputData = new String(readBuff, 0, count);
sb.Append(outputData);
count = streamRead.Read(readBuff, 0, 256);
}
// Close the Stream Object.
streamResponse.Close();
streamRead.Close();
//allDone.WaitOne();
// Release the HttpWebResponse Resource.
response.Close();
//return sb.ToString();
} catch (WebException webex) {
Debug.WriteLine(webex.Message);
} catch (System.Web.Services.Protocols.SoapException soapex) {
Debug.WriteLine(soapex.Message);
} catch (System.Net.ProtocolViolationException ex) {
Debug.WriteLine(ex.Message);
} catch (Exception ex) {
Debug.WriteLine(ex.Message);
}
return sb.ToString();
}
private static void ReadCallBack(IAsyncResult asyncResult)
{
try {
RequestState myRequestState = (RequestState)asyncResult.AsyncState;
WebRequest myWebRequest2 = myRequestState.Request;
// End of the Asynchronus request.
Stream responseStream = myWebRequest2.EndGetRequestStream(asyncResult);
//Convert the string into a byte array.
ASCIIEncoding encoder = new ASCIIEncoding();
byte[] ByteArray = encoder.GetBytes(myRequestState.Xml);
// Write data to the stream.
responseStream.Write(ByteArray, 0, myRequestState.Xml.Length);
responseStream.Close();
} catch (WebException e) {
Console.WriteLine("\nReadCallBack Exception raised!");
Console.WriteLine("\nMessage:{0}", e.Message);
Console.WriteLine("\nStatus:{0}", e.Status);
}
allDone.Set();
}
response =request.GetResponse()
is when it fails and gives an error
You must provide a request body if you set ContentLength>0 or SendChunked==true. Do this by calling [Begin]GetRequestStream before [Begin]GetResponse.
Any help would be greatly appreciated.
This gets tricky since we're doing async calls.
Do this in the following order:
request.BeginGetRequestStream(new AsyncCallback(GetRequestStreamCallback), request)
Then in 'GetRequestStreamCallback(IAsyncResult asynchronousResult)' call:
request.BeginGetResponse(new AsyncCallback(GetResponseCallback), request)
Lastly, in the GetResponse, be sure to close the stream:
response.Close();
allDone.Set();
MSDN Does a really good job explaining it: http://msdn.microsoft.com/en-us/library/system.net.httpwebrequest.begingetrequeststream.aspx