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Adding parameters to an HttpWebRequest

This question has been asked a million times, and yet none of the responses work for me. The one I was most excited about was Http Post for Windows Phone 8 but because it requires delegates, it's not right for my code... the Postdata function is called from repositories, it would be nice to get a response straight from this function!
How do I add post parameters to this code? I've been trying to get it to work for a good 10 hours now.
// Repository code
string url = "/bla/bla/" + blaId + "/";
Dictionary<string, string> postParams = new Dictionary<string, string>();
postParams.Add("value", message);
string response = await BlaDataContext.PostData(url, postParams);
// ...
public static async Task<string> PostData(string url, Dictionary<String, String> postParams)
{
HttpWebRequest request = WebRequest.CreateHttp(APIURL + url);
request.ContentType = "application/x-www-form-urlencoded";
request.Method = "POST";
postParams.Add("oauth_token", Contract.AccessToken); // where do I add this to the request??
try
{
HttpWebResponse response = (HttpWebResponse)await request.GetResponseAsync();
Debug.WriteLine(response.ContentType);
Stream responseStream = response.GetResponseStream();
string data;
using (var reader = new StreamReader(responseStream))
{
data = reader.ReadToEnd();
}
responseStream.Close();
return data;
}
catch (Exception e)
{
// whatever
}
}

HttpWebRequest request = WebRequest.CreateHttp("" + url);
//we could move the content-type into a function argument too.
request.ContentType = "application/x-www-form-urlencoded";
request.Method = "POST";
postParams.Add("oauth_token", ""); // where do I add this to the request??
try
{
//this is how you do it
using(var stream = await request.GetRequestStreamAsync())
{
byte[] jsonAsBytes = Encoding.UTF8.GetBytes(string.Join("&", postParams.Select(pp => pp.Key + "=" + pp.Value)));
await stream.WriteAsync(jsonAsBytes, 0, jsonAsBytes.Length);
}
HttpWebResponse response = (HttpWebResponse)await request.GetResponseAsync();
Debug.WriteLine(response.ContentType);
System.IO.Stream responseStream = response.GetResponseStream();
string data;
using (var reader = new System.IO.StreamReader(responseStream))
{
data = reader.ReadToEnd();
}
responseStream.Close();
return data;
}
Async Await HttpWebRequest Extensions:
public static class HttpExtensions
{
public static Task<Stream> GetRequestStreamAsync(this HttpWebRequest request)
{
var tcs = new TaskCompletionSource<Stream>();
try
{
request.BeginGetRequestStream(iar =>
{
try
{
var response = request.EndGetRequestStream(iar);
tcs.SetResult(response);
}
catch (Exception exc)
{
tcs.SetException(exc);
}
}, null);
}
catch (Exception exc)
{
tcs.SetException(exc);
}
return tcs.Task;
}
public static Task<HttpWebResponse> GetResponseAsync(this HttpWebRequest request)
{
var taskComplete = new TaskCompletionSource<HttpWebResponse>();
request.BeginGetResponse(asyncResponse =>
{
try
{
HttpWebRequest responseRequest = (HttpWebRequest)asyncResponse.AsyncState;
HttpWebResponse someResponse =
(HttpWebResponse)responseRequest.EndGetResponse(asyncResponse);
taskComplete.TrySetResult(someResponse);
}
catch (WebException webExc)
{
HttpWebResponse failedResponse = (HttpWebResponse)webExc.Response;
taskComplete.TrySetResult(failedResponse);
}
}, request);
return taskComplete.Task;
}
}
With the extensions, I think it's a little cleaner.

You need to write the parameters to the request body.
You could use an extension method like this one:
public static void AddFormData(this HttpWebRequest request, IDictionary<string, string> data)
{
using (var memStream = new MemoryStream())
using (var writer = new StreamWriter(memStream))
{
bool first = true;
foreach (var d in data)
{
if (!first)
writer.Append("&");
writer.Write(Uri.EscapeDataString(d.Key));
writer.Write("=");
writer.Write(Uri.EscapeDataString(d.Value));
first = false;
}
writer.Flush();
request.ContentLength = memStream.Length;
memStream.Position = 0;
using (var reqStream = request.GetRequestStream())
{
memStream.CopyTo(reqStream);
}
}
}
Call it like this:
request.AddFormData(postParams);

Sending HTTP POST Request with XML to a web service and reading response data in C# for windows 8 phone

I a newbie at windows 8 phone development. I want to send an aync HTTP POST Request to a PHP web service with some headers and XML in the request body.
Also, I want to read the response sent back by the PHP web service.
Please guide me, how can I achieve the above two stated things.
what I have tried until now i am giving below
// Main begins program execution.
public static void SendRequest()
{
HttpWebRequest webRequest = (HttpWebRequest)HttpWebRequest.CreateHttp("http://mytestserver.com/Test.php");
webRequest.Method = "POST";
webRequest.ContentType = "text/xml";
webRequest.Headers["SOURCE"] = "WinApp";
var response = await httpRequest(webRequest);
}
public static async Task<string> httpRequest(HttpWebRequest request)
{
string received;
using (var response = (HttpWebResponse)(await Task<WebResponse>.Factory.FromAsync(request.BeginGetResponse, request.EndGetResponse, null)))
{
using (var responseStream = response.GetResponseStream())
{
using (var sr = new StreamReader(responseStream))
{
received = await sr.ReadToEndAsync();
MessageBox.Show(received.ToString());
}
}
}
return received;
}
I am able to send the request using the above code. I just need to know that how I can send the XML in the request body to my web service.

For Set a file, and receive a server Response, I use that for sending .csv files:
First I initialize a POST Request:
/// <summary>
/// Initialize the POST HTTP request.
/// </summary>
public void SentPostReport()
{
string url = "http://MyUrlPerso.com/";
Uri uri = new Uri(url);
// Create a boundary for HTTP request.
Boundary = "----------------------------" + DateTime.Now.Ticks.ToString("x");
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
request.ContentType = "multipart/form-data; boundary=" + Boundary;
request.Method = "POST";
request.BeginGetRequestStream(new AsyncCallback(GetRequestStreamCallback), est);
allDone.WaitOne();
}
After initialized Request, I send the differents parts of my files (headers + content + footer).
/// <summary>
/// Send a File with initialized request.
/// </summary>
private void GetRequestStreamCallback(IAsyncResult asynchronousResult)
{
string contentType = "binary";
string myFileContent = "one;two;three;four;five;"; // CSV content.
HttpWebRequest request = (HttpWebRequest)asynchronousResult.AsyncState;
Stream memStream = request.EndGetRequestStream(asynchronousResult);
byte[] boundarybytes = System.Text.Encoding.UTF8.GetBytes("\r\n--" + Boundary + "\r\n");
memStream.Write(boundarybytes, 0, boundarybytes.Length);
// Send headers.
string headerTemplate = "Content-Disposition: form-data; ";
headerTemplate += "name=\"{0}\"; filename=\"{1}\"\r\nContent-Type: " + contentType + "\r\n\r\n";
string fileName = "MyFileName.csv";
string header = string.Format(headerTemplate, "file", fileName);
byte[] headerbytes = System.Text.Encoding.UTF8.GetBytes(header);
memStream.Write(headerbytes, 0, headerbytes.Length);
byte[] contentbytes = System.Text.Encoding.UTF8.GetBytes(myFileContent);
// send the content of the file.
memStream.Write(contentbytes, 0, contentbytes.Length);
// Send last boudary of the file ( the footer) for specify post request is finish.
byte[] boundarybytesend = System.Text.Encoding.UTF8.GetBytes("\r\n--" + Boundary + "--\r\n");
memStream.Write(boundarybytesend, 0, boundarybytesend.Length);
memStream.Flush();
memStream.Close();
allDone.Set();
// Start the asynchronous operation to get the response
request.BeginGetResponse(new AsyncCallback(GetResponseCallback), request);
}
And, Finnaly, I get The response server response, indicate the file is transmetted.
/// <summary>
/// Get the Response server.
/// </summary>
private static void GetResponseCallback(IAsyncResult asynchronousResult)
{
HttpWebRequest request = (HttpWebRequest)asynchronousResult.AsyncState;
try
{
HttpWebResponse response = (HttpWebResponse)request.EndGetResponse(asynchronousResult);
Stream streamResponse = response.GetResponseStream();
StreamReader streamRead = new StreamReader(streamResponse);
string responseString = streamRead.ReadToEnd(); // this is a response server.
// Close the stream object
streamResponse.Close();
streamRead.Close();
// Release the HttpWebResponse
response.Close();
}
catch (Exception ex)
{
// error.
}
}
This sample works on Windows Phone 7 and Windows Phone 8.
This is for send a .csv content. You can adapt this code for send Xml content.
Replace just
string myFileContent = "one;two;three;four;five;"; // CSV content.
string fileName = "MyFileName.csv";
by your XML
string myFileContent = "<xml><xmlnode></xmlnode></xml>"; // XML content.
string fileName = "MyFileName.xml";

If all you're looking to do is take XML you've already generated and add it to your existing request as content, you'll need to be able to write to the request stream. I don't particularly care for the stock model of getting the request stream, so I'd recommend the following extension to make your life a little easier:
public static class Extensions
{
public static System.Threading.Tasks.Task<System.IO.Stream> GetRequestStreamAsync(this System.Net.HttpWebRequest wr)
{
if (wr.ContentLength < 0)
{
throw new InvalidOperationException("The ContentLength property of the HttpWebRequest must first be set to the length of the content to be written to the stream.");
}
var tcs = new System.Threading.Tasks.TaskCompletionSource<System.IO.Stream>();
wr.BeginGetRequestStream((result) =>
{
var source = (System.Net.HttpWebRequest)result.AsyncState;
tcs.TrySetResult(source.EndGetRequestStream(result));
}, wr);
return tcs.Task;
}
}
From here, augment your SendRequest method:
public static void SendRequest(string myXml)
{
HttpWebRequest webRequest = (HttpWebRequest)HttpWebRequest.CreateHttp("http://mytestserver.com/Test.php");
webRequest.Method = "POST";
webRequest.Headers["SOURCE"] = "WinApp";
// Might not hurt to specify encoding here
webRequest.ContentType = "text/xml; charset=utf-8";
// ContentLength must be set before a stream may be acquired
byte[] content = System.Text.Encoding.UTF8.GetBytes(myXml);
webRequest.ContentLength = content.Length;
var reqStream = await webRequest.GetRequestStreamAsync();
reqStream.Write(content, 0, content.Length);
var response = await httpRequest(webRequest);
}
If the service you're trying to reach is a SOAP service, you could simplify this a bit more by having the IDE generate a client class for you. For more information on how to do that, check out this MSDN article. However, if the service does not have a Web Service Definition Language (WSDL) document, this approach will not be able to assist you.

You can use the HTTP Client libraries in Windows Phone 8 and use the client in the same way that Windows 8.
First, get the HTTP Client Libraries from Nuget.
And now, to perform a POST call
HttpClient client = new HttpClient();
HttpContent httpContent = new StringContent("my content: xml, json or whatever");
httpContent.Headers.Add("name", "value");
HttpResponseMessage response = await client.PostAsync("uri", httpContent);
if (response.IsSuccessStatusCode)
{
// DO SOMETHING
}
i hope this helps you :)

I have solved the problem in some other way..
class HTTPReqRes
{
private static HttpWebRequest webRequest;
public static void SendRequest()
{
webRequest = (HttpWebRequest)HttpWebRequest.CreateHttp("https://www.mydomain.com");
webRequest.Method = "PUT";
webRequest.ContentType = "text/xml; charset=utf-8";
webRequest.Headers["Header1"] = "Header1Value";
String myXml = "<Roottag><info>test</info></Roottag>";
// Convert the string into a byte array.
byte[] byteArray = Encoding.UTF8.GetBytes(myXml);
webRequest.ContentLength = byteArray.Length;
// start the asynchronous operation
webRequest.BeginGetRequestStream(new AsyncCallback(GetRequestStreamCallback), webRequest);
//webRequest.BeginGetResponse(new AsyncCallback(GetResponseCallback), webRequest);
}
private static void GetRequestStreamCallback(IAsyncResult asynchronousResult)
{
HttpWebRequest request = (HttpWebRequest)asynchronousResult.AsyncState;
// End the operation
Stream postStream = request.EndGetRequestStream(asynchronousResult);
String myXml = <Roottag><info>test</info></Roottag>";
// Convert the string into a byte array.
byte[] byteArray = Encoding.UTF8.GetBytes(myXml);
// Write to the request stream.
postStream.Write(byteArray, 0, byteArray.Length);
postStream.Close();
// Start the asynchronous operation to get the response
request.BeginGetResponse(new AsyncCallback(GetResponseCallback), request);
}
private static void GetResponseCallback(IAsyncResult asynchronousResult)
{
HttpWebRequest request = (HttpWebRequest)asynchronousResult.AsyncState;
// End the operation
HttpWebResponse response = (HttpWebResponse)request.EndGetResponse(asynchronousResult);
Stream streamResponse = response.GetResponseStream();
StreamReader streamRead = new StreamReader(streamResponse);
string responseString = streamRead.ReadToEnd();
System.Diagnostics.Debug.WriteLine(responseString);
// Close the stream object
streamResponse.Close();
streamRead.Close();
// Release the HttpWebResponse
response.Close();
}
}
This perfectly solves my problem, send an XML within the HTTP Request and in Response receive the XML from the web service.

I recommend using the RestSharp library. You can find a sample request here.

This is what I used. It's really simple, add WindowsPhonePostClient.dll to your References (if you can't, try unblock the file first by properties->unblock), then use this code:
private void Post(string YourUsername, string Password)
{
Dictionary<string, object> parameters = new Dictionary<string, object>();
parameters.Add("User", YourUsername);
parameters.Add("Password", Password);
PostClient proxy = new PostClient(parameters);
proxy.DownloadStringCompleted += proxy_UploadDownloadStringCompleted;
proxy.DownloadStringAsync(new Uri("http://mytestserver.com/Test.php",UriKind.Absolute));
}
private void proxy_UploadDownloadStringCompleted(object sender,WindowsPhonePostClient.DownloadStringCompletedEventArgs e)
{
if (e.Error == null)
MessageBox.Show(e.Result.ToString());
}

You need to create a reference to the webservice wsdl or you could try to do it manually as detailed here:
https://stackoverflow.com/a/1609427/2638872

//The below code worked for me. I receive xml response back.
private void SendDataUsingHttps()
{
WebRequest req = null;
WebResponse rsp = null;
string fileName = #"C:\Test\WPC\InvoiceXMLs\123File.xml"; string uri = "https://service.XYZ.com/service/transaction/cxml.asp";
try
{
if ((!string.IsNullOrEmpty(uri)) && (!string.IsNullOrEmpty(fileName)))
{
req = WebRequest.Create(uri);
//req.Proxy = WebProxy.GetDefaultProxy(); // Enable if using proxy
req.Method = "POST"; // Post method
req.ContentType = "text/xml"; // content type
// Wrap the request stream with a text-based writer
StreamWriter writer = new StreamWriter(req.GetRequestStream());
// Write the XML text into the stream
StreamReader reader = new StreamReader(file);
string ret = reader.ReadToEnd();
reader.Close();
writer.WriteLine(ret);
writer.Close();
// Send the data to the webserver
rsp = req.GetResponse();
HttpWebResponse hwrsp = (HttpWebResponse)rsp;
Stream streamResponse = hwrsp.GetResponseStream();
StreamReader streamRead = new StreamReader(streamResponse);
string responseString = streamRead.ReadToEnd();
rsp.Close();
}
}
catch (WebException webEx) { }
catch (Exception ex) { }
finally
{
if (req != null) req.GetRequestStream().Close();
if (rsp != null) rsp.GetResponseStream().Close();
}
}

How to make ordinary WebRequest async and awaitable?

I need to make the following code async and awaitable.
I need to get a lot of data from the web server, and then this data will be used to populate the xaml page in my application.
So, I need the DefLogin() method to be awaitable.
Is it possible?
public void DefLogin()
{
postData = "My Data To Post";
var url = new Uri("Url To Post to", UriKind.Absolute);
webRequest = WebRequest.Create(url);
webRequest.Method = "POST";
webRequest.ContentType = "text/xml";
webRequest.BeginGetRequestStream(new AsyncCallback(GetRequestStreamCallback), webRequest);
}
public void GetRequestStreamCallback(IAsyncResult asynchronousResult)
{
webRequest = (HttpWebRequest)asynchronousResult.AsyncState;
Stream postStream = webRequest.EndGetRequestStream(asynchronousResult);
byte[] byteArray = Encoding.UTF8.GetBytes(postData);
postStream.Write(byteArray, 0, byteArray.Length);
postStream.Close();
Debug.WriteLine("Start BEGINGetResponse");
webRequest.BeginGetResponse(new AsyncCallback(GetResponseCallback), webRequest);
}
public void GetResponseCallback(IAsyncResult asynchronousResult)
{
try
{
HttpWebRequest webRequest = (HttpWebRequest)asynchronousResult.AsyncState;
HttpWebResponse response;
response = (HttpWebResponse)webRequest.EndGetResponse(asynchronousResult);
Stream streamResponse = response.GetResponseStream();
StreamReader streamReader = new StreamReader(streamResponse);
string Response = streamReader.ReadToEnd();
streamResponse.Close();
streamReader.Close();
response.Close();
if (Response == "")
{
//show some error msg to the user
Debug.WriteLine("ERROR");
}
else
{
//Your response will be available in "Response"
Debug.WriteLine(Response);
}
}
catch (WebException)
{
//error
}
}
I saw this question on StackOverflow: Converting ordinary Http Post web request with Async and Await, but I could not understand the answer properly.
Please can anyone help? I would be really grateful!

You can use TaskFactory.FromAsync to convert APM to TAP, making a lot of tiny extension methods like this:
public static Task<Stream> GetRequestStreamAsync(this WebRequest request)
{
return TaskFactory.FromAsync(request.BeginGetRequestStream, request.EndGetRequestStream, null);
}
and do the same for WebRequest.GetResponse and (if necessary) Stream.Write, Stream.Flush, etc.
Then you can write your actual logic using async and await without any callbacks:
public async Task DefLoginAsync()
{
postData = "My Data To Post";
var url = new Uri("Url To Post to", UriKind.Absolute);
webRequest = WebRequest.Create(url);
webRequest.Method = "POST";
webRequest.ContentType = "text/xml";
using (Stream postStream = await webRequest.GetRequestStreamAsync())
{
byte[] byteArray = Encoding.UTF8.GetBytes(postData);
await postStream.WriteAsync(byteArray, 0, byteArray.Length);
await postStream.FlushAsync();
}
try
{
string Response;
using (var response = (HttpWebResponse)await webRequest.GetResponseAsync());
using (Stream streamResponse = response.GetResponseStream())
using (StreamReader streamReader = new StreamReader(streamResponse))
{
Response = await streamReader.ReadToEndAsync();
}
if (Response == "")
{
//show some error msg to the user
Debug.WriteLine("ERROR");
}
else
{
//Your response will be available in "Response"
Debug.WriteLine(Response);
}
}
catch (WebException)
{
//error
}
}

POST an image using HttpWebRequest with Json response - WP7

I'm using some of the code I found on here to POST an image to a server. The problem is that I am not receiving the Json response that I should be, instead I'm getting the ol' SERVER NOT FOUND response in my "ResponseReady" callback. (EDIT: Turns out it was just my parameters, this code works perfectly fine.)
Here is the class I am using to make the POST
public class PostSubmitter
{
public string url { get; set; }
public Dictionary<string, object> parameters { get; set; }
string boundary = "----------" + DateTime.Now.Ticks.ToString();
HttpWebRequest webRequest;
public void Submit()
{
// Prepare web request...
webRequest = WebRequest.CreateHttp(url);
webRequest.Method = "POST";
webRequest.ContentType = string.Format("multipart/form-data; boundary={0}", boundary);
webRequest.BeginGetRequestStream(new AsyncCallback(RequestReady), webRequest);
}
private void RequestReady(IAsyncResult asynchronousResult)
{
using (Stream postStream = webRequest.EndGetRequestStream(asynchronousResult))
{
writeMultipartObject(postStream, parameters);
}
webRequest.BeginGetResponse(new AsyncCallback(ResponseReady), webRequest);
}
private void ResponseReady(IAsyncResult asynchronousResult)
{
try
{
using (var response =
(HttpWebResponse)webRequest.EndGetResponse(asynchronousResult))
using (var streamResponse = response.GetResponseStream())
using (var streamRead = new StreamReader(streamResponse))
{
var responseString = streamRead.ReadToEnd();
var success = response.StatusCode == HttpStatusCode.OK;
if (responseString != null)
{
//JObject comes from Newtonsoft.Json ddl. This is a good one if your working with json
JObject jsonResponse = JObject.Parse(responseString);
//Do stuff with json.....
}
}
}
catch (Exception e)
{
if (e.Message == "The remote server returned an error: NotFound.")
{
webRequest.Abort();
Deployment.Current.Dispatcher.BeginInvoke(delegate() { MessageBox.Show("Unable to connect to server at this time, please try again later"); });
}
else
Deployment.Current.Dispatcher.BeginInvoke(delegate() { MessageBox.Show("Unable to upload photo at this time, please try again later"); });
return;
}
}
public void writeMultipartObject(Stream stream, object data)
{
using (StreamWriter writer = new StreamWriter(stream))
{
if (data != null)
{
foreach (var entry in data as Dictionary<string, object>)
{
WriteEntry(writer, entry.Key, entry.Value);
}
}
writer.Write("--");
writer.Write(boundary);
writer.WriteLine("--");
writer.Flush();
}
}
private void WriteEntry(StreamWriter writer, string key, object value)
{
if (value != null)
{
writer.Write("--");
writer.WriteLine(boundary);
if (value is byte[])
{
byte[] ba = value as byte[];
writer.WriteLine(#"Content-Disposition: form-data; name=""{0}""; filename=""{1}""", key, "sentPhoto.jpg");
writer.WriteLine(#"Content-Type: application/octet-stream");
writer.WriteLine(#"Content-Type: image / jpeg");
writer.WriteLine(#"Content-Length: " + ba.Length);
writer.WriteLine();
writer.Flush();
Stream output = writer.BaseStream;
output.Write(ba, 0, ba.Length);
output.Flush();
writer.WriteLine();
}
else
{
writer.WriteLine(#"Content-Disposition: form-data; name=""{0}""", key);
writer.WriteLine();
writer.WriteLine(value.ToString());
}
}
}
}
Using this class we can then make a simple POST to the server with the following lines of code:
Dictionary<string, object> postData = new Dictionary<string, object>()
{
{"file", byteArrayOfImage}
//You can add other parameters here
};
PostSubmitter postToServer = new PostSubmitter() { url = getPicturePostUrl(), parameters = postData };
postToServer.Submit();
There are so many questions out there on this... you'd think they'd make it easier to do complex web requests....
Thanks in advance for your helpful comments or feel free to ask a question.

Well this code actually works perfectly. I just didn't have one of the required parameters so the server was rejecting the request.

WP7 app never exits BeginGetResponse and goes into the callback function

I have the following code:
private void GetRequestStreamCallback(IAsyncResult asynchronousResult)
{
HttpWebRequest request = (HttpWebRequest)asynchronousResult.AsyncState;
// End the operation
Stream postStream = request.EndGetRequestStream(asynchronousResult);
//Console.WriteLine("Please enter the input data to be posted:");
//string postData = Console.ReadLine();
string postData = "my data";
// Convert the string into a byte array.
byte[] byteArray = Encoding.UTF8.GetBytes(postData);
// Write to the request stream.
postStream.Write(byteArray, 0, postData.Length);
postStream.Close();
// Start the asynchronous operation to get the response
IAsyncResult result =
(IAsyncResult)request.BeginGetResponse(new AsyncCallback(GetResponseCallback), request);
}
private void GetResponseCallback(IAsyncResult asynchronousResult)
{
HttpWebRequest request = (HttpWebRequest)asynchronousResult.AsyncState;
// End the operation
HttpWebResponse response = (HttpWebResponse)request.EndGetResponse(asynchronousResult);
Stream streamResponse = response.GetResponseStream();
StreamReader streamRead = new StreamReader(streamResponse);
string responseString = streamRead.ReadToEnd();
Console.WriteLine(responseString);
// Close the stream object
streamResponse.Close();
streamRead.Close();
// Release the HttpWebResponse
response.Close();
allDone.Set();
Dispatcher.BeginInvoke((Action)(() => Debug.WriteLine("George")));
}
However when my code hits BeginGetResponse it never exits (and I do not hit a breakpoint in the GetResponseCallback function). I tried adding the BeginInvoke call, but I still never enter this method. This code works in a windows console app - it's on Windows Phone 7 that it doesn'teorg
Can anyone see what I am doing wrong?
Thanks.

If you have created the HttpWebRequest on the UI thread, then make sure you don't block the UI thread, otherwise you can deadlock.
The sample from the desktop .NET you have linked isn't optimized for the current phone networking stack. You should change the code so that you create the HttpWebRequest on a background thread.

I can't see what's wrong with your code (maybe a complete example of what you're trying to do may help) but here's a simple working example of a way of performing the action you want to do.
It posts some data to a URI and then passes the repsonse to a callback function:
Simply execute like this (use of a BackgroundWorker is not necessary but is recommended)
var bw = new BackgroundWorker();
bw.DoWork += (o, args) => PostDataToWebService("http://example.com/something", "key=value&key2=value2", MyCallback);
bw.RunWorkerAsync();
Here's the callback function it refers to:
(You can change this however is appropriate to your needs.)
public static void MyCallback(string aString, Exception e)
{
Deployment.Current.Dispatcher.BeginInvoke(() =>
{
if (e == null)
{
// aString is the response from the web server
MessageBox.Show(aString, "success", MessageBoxButton.OK);
}
else
{
MessageBox.Show(e.Message, "error", MessageBoxButton.OK);
}
});
}
Here's the actual method:
public void PostDataToWebService(string url, string data, Action<string, Exception> callback)
{
if (callback == null)
{
throw new Exception("callback may not be null");
}
try
{
var uri = new Uri(url, UriKind.Absolute);
var req = HttpWebRequest.CreateHttp(uri);
req.ContentType = "application/x-www-form-urlencoded";
req.Method = "POST";
AsyncCallback GetTheResponse = ar =>
{
try
{
var result = ar.GetResponseAsString();
callback(result, null);
}
catch (Exception ex)
{
callback(null, ex);
}
};
AsyncCallback SetTheBodyOfTheRequest = ar =>
{
var request = ar.SetRequestBody(data);
request.BeginGetResponse(GetTheResponse, request);
};
req.BeginGetRequestStream(SetTheBodyOfTheRequest, req);
}
catch (Exception ex)
{
callback(null, ex);
}
}
and here are the extension/helper methods it uses:
public static class IAsyncResultExtensions
{
public static string GetResponseAsString(this IAsyncResult asyncResult)
{
string responseString;
var request = (HttpWebRequest)asyncResult.AsyncState;
using (var resp = (HttpWebResponse)request.EndGetResponse(asyncResult))
{
using (var streamResponse = resp.GetResponseStream())
{
using (var streamRead = new StreamReader(streamResponse))
{
responseString = streamRead.ReadToEnd();
}
}
}
return responseString;
}
public static HttpWebRequest SetRequestBody(this IAsyncResult asyncResult, string body)
{
var request = (HttpWebRequest)asyncResult.AsyncState;
using (var postStream = request.EndGetRequestStream(asyncResult))
{
using (var memStream = new MemoryStream())
{
var content = body;
var bytes = System.Text.Encoding.UTF8.GetBytes(content);
memStream.Write(bytes, 0, bytes.Length);
memStream.Position = 0;
var tempBuffer = new byte[memStream.Length];
memStream.Read(tempBuffer, 0, tempBuffer.Length);
postStream.Write(tempBuffer, 0, tempBuffer.Length);
}
}
return request;
}
}