POST Requests on WP7 - silverlight

I've been dying for about 6 hours trying to figure out how to make a regular POST request in WP7 , I tried the answers of similar questions posted here and on many other places, I also tried many different APIs POST request, they all lead to one certain problem,
The remote server returned an error: NotFound.
it seems like everytime there's something missing.
So, if you please someone show us how to properly get a POST request right in this WP7

I use this to post to facebook without any problem:
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(requestUrl);
request.Method = "POST";
request.BeginGetResponse((e) =>
{
try
{
WebResponse response = request.EndGetResponse(e);
// Do Stuff
}
catch (WebException ex)
{
// Handle
}
catch (Exception ex)
{
// Handle
}
}, null);
I assume you would have tried this already so it may be something to do with the post data (which isn't in the above example as facebook uses the query string). Can you give us any more info?
EDIT: This is an (untested) example for writing post data:
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(requestUrl);
request.Method = "POST";
request.BeginGetRequestStream((e) =>
{
using (Stream stream = request.EndGetRequestStream(e))
{
// Write data to the request stream
}
request.BeginGetResponse((callback) =>
{
try
{
WebResponse response = request.EndGetResponse(callback);
// Do Stuff
}
catch (WebException ex)
{
// Handle
}
catch (Exception ex)
{
// Handle
}
}, null);
}, null);

I use the following class for making POST requests with WP7:
public class PostMultiPartFormData
{
private Dictionary<string, object> Parameters;
private Encoding ENCODING = Encoding.UTF8;
private string BOUNDARY = "-----------------------------wp7postrequest";
public event EventHandler PostComplete;
public void Post(string postbackURL,
Dictionary<string, object> parameters)
{
Parameters = parameters;
Uri url = null;
url = new Uri(postbackURL);
HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest;
request.Method = "POST";
request.ContentType = "multipart/form-data; boundary=" + BOUNDARY;
request.BeginGetRequestStream(new AsyncCallback(SendStatusUpdate), request);
}
private void SendStatusUpdate(IAsyncResult ar)
{
HttpWebRequest request = (HttpWebRequest)ar.AsyncState;
Stream stream = request.EndGetRequestStream(ar);
byte[] byteArray = GetMultipartFormData(Parameters, BOUNDARY);
stream.Write(byteArray, 0, byteArray.Length);
stream.Close();
stream.Dispose();
request.BeginGetResponse(new AsyncCallback(StatusUpdateCompleted), request);
}
private byte[] GetMultipartFormData(Dictionary<string, object> postParameters, string boundary)
{
Stream formDataStream = new System.IO.MemoryStream();
foreach (var param in postParameters)
{
if (param.Value is byte[])
{
byte[] fileData = param.Value as byte[];
string header = string.Format("--{0}\r\nContent-Disposition: form-data; name=\"{1}\"; filename=\"{2}.jpg\";\r\nContent-Type: application/octet-stream\r\n\r\n", boundary, param.Key, param.Key);
formDataStream.Write(ENCODING.GetBytes(header), 0, header.Length);
formDataStream.Write(fileData, 0, fileData.Length);
}
else
{
string postData = string.Format("--{0}\r\nContent-Disposition: form-data; name=\"{1}\"\r\n\r\n{2}\r\n", boundary, param.Key, param.Value);
byte[] b = ENCODING.GetBytes(postData);
foreach (var item in b)
{
formDataStream.WriteByte(item);
}
}
}
string footer = "\r\n--" + boundary + "--\r\n";
byte[] footerbytes = ENCODING.GetBytes(footer);
formDataStream.Write(footerbytes, 0, footerbytes.Length);
formDataStream.Position = 0;
byte[] formData = new byte[formDataStream.Length];
formDataStream.Read(formData, 0, formData.Length);
formDataStream.Flush();
formDataStream.Close();
return formData;
}
private void StatusUpdateCompleted(IAsyncResult ar)
{
if (PostComplete != null)
{
PostComplete(ar, null);
}
}
}
Example:
PostMultiPartFormData postRequest = new PostMultiPartFormData();
postRequest.PostComplete += new EventHandler( (sender, e) =>
{
IAsyncResult ar = ((IAsyncResult)sender);
using (WebResponse resp = ((HttpWebRequest)ar.AsyncState).EndGetResponse(ar))
{
using (StreamReader sr = new StreamReader(resp.GetResponseStream()))
{
string responseString = sr.ReadToEnd();
this.Dispatcher.BeginInvoke(() =>
{
textBlock.Text = responseString;
});
}
}
});
postRequest.Post("http://localhost:50624/SSLProxy.ashx",
new Dictionary<string, object>() { { "param1", "value1" } });
This should work...
If it doesn't let me know! :-)

For easier access to advanced http features check out these http classes:
http://mytoolkit.codeplex.com/wikipage?title=Http
It encapsulates GET, POST, FILES (using path or Stream objects) and GZIP (not directly supported by WP7) requests.

To add post data just call BeginGetRequestStream method (also, BeginGetResponse move to GetRequestStreamCallback)
request.BeginGetRequestStream(new AsyncCallback(GetRequestStreamCallback), request);
void GetRequestStreamCallback(IAsyncResult asynchronousResult)
{
HttpWebRequest webRequest = (HttpWebRequest)asynchronousResult.AsyncState;
// End the stream request operation
Stream postStream = webRequest.EndGetRequestStream(asynchronousResult);
// Create the post data
string postData = "post data";
byte[] byteArray = Encoding.Unicode.GetBytes(postData);
// Add the post data to the web request
postStream.Write(byteArray, 0, byteArray.Length);
postStream.Close();
// Start the web request
webRequest.BeginGetResponse(new AsyncCallback(GetResponseCallback), webRequest);
}

I recommend you to use the postclient. It is pretty simple. You just need to add reference to dll file into your project, and then write something like:
public void authorize(string login, string password)
{
Dictionary<string, object> parameters = new Dictionary<string, object>();
parameters.Add("command", "login");
parameters.Add("username", login);
parameters.Add("password", password);
PostClient proxy = new PostClient(parameters);
proxy.DownloadStringCompleted += (sender, e) =>
{
if (e.Error == null)
{
MessageBox.Show(e.Result);
}
};
proxy.DownloadStringAsync(new Uri("http://address.com/service", UriKind.Absolute));
}

Related

HttpWebRequest in Silverlight

How to recreate the following code in Silverlight? I'm pretty lost when it comes to async.
public class StringGet
{
public static string GetPageAsString(Uri address)
{
string result = "";
// Create the web request
HttpWebRequest request = WebRequest.Create(address) as HttpWebRequest;
// Get response
using (HttpWebResponse response = request.GetResponse() as HttpWebResponse)
{
// Get the response stream
StreamReader reader = new StreamReader(response.GetResponseStream());
// Read the whole contents and return as a string
result = reader.ReadToEnd();
}
return result;
}
public void DownloadHtml(Uri address){
WebClient webClient = new WebClient();
webClient.DownloadStringCompleted += WebClientDownloadString_Complete;
webClient.DownloadStringAsync(address)
}
private void WebClientDownloadString_Complete(object sender, DownloadStringCompletedEventArgs e) {
if (e.Error == null) {
string html = e.Result;
}
}

How do I update the UI from a HttpWebRequest?

In my Mainpage.xaml.cs file I have a function that creates an instance of another class and tries to download a webpage using a HttpWebRequest from that instance. The problem is, once I've managed to download the webpage I can't send it back to the main UI thread. I've tried using Deployment.Current.Dispatcher.BeginInvoke to send the webpage back to a TextBlock I have waiting, but when I try I get an error telling me that I can't access the TextBlock from the other class. Is there any way to pass data between two threads without using LocalStorage?
EDIT: code below:
MainPage:
private void button1_Click(object sender, RoutedEventArgs e)
{
Member m = new Member(name, id);
}
Member class:
public Member(String Member, String API)
{
APIKey = API;
MemberName = Member;
this.super = super;
DoSend(method, string, "", null);
}
public void DoSend(string method, string url, string body, string mimetype)
{
if (WebRequest.RegisterPrefix("https://",System.Net.Browser.WebRequestCreator.ClientHttp)) {
HttpWebRequest request = WebRequest.Create(makeURI(url)) as HttpWebRequest;
request.Method = method;
request.Headers["X-NFSN-Authentication"] = MakeAuthHeader(url,body);
if (body != "")
{
byte[] bodyData = Encoding.UTF8.GetBytes(body);
request.ContentType = mimetype;
//Stuff Should Happen Here
}
else
doStuff(request);
}
public void doStuff(HttpWebRequest httpReq)
{
httpReq.BeginGetResponse(r =>
{
var httpRequest = (HttpWebRequest)r.AsyncState;
var httpResponse = (HttpWebResponse)httpRequest.EndGetResponse(r);
using (var reader = new StreamReader(httpResponse.GetResponseStream()))
{
var response = reader.ReadToEnd();
ResponseBlock.Text = response; //Invalid cross-thread reference
}
}, httpReq);
}
MainPage:
customClass.DownloadPage((result) =>
{
textBlock.Text = result;
},
(exception) =>
{
MessageBox.Show(exception.Message);
});
CustomClass:
public void DownloadPage(Action<string> callback, Action<Exception> exception)
{
WebClient webClient = new WebClient();
webClient.DonwloadStringCompleted += (s, e) =>
{
if (e.Error == null)
{
Deployment.Current.Dispatcher.BeginInvoke(() =>
{
callback(e.Result);
});
}
else
{
Deployment.Current.Dispatcher.BeginInvoke(() =>
{
exception(e.Error);
});
}
};
webClient.DonwloadStringAsync();
}

HttpWebRequest "POST" returning server error (Exception)

I'm trying to call the google URL shortner API from a WP7 app, I tried first on a Console Application by doing this:
var httpWebRequest = (HttpWebRequest)WebRequest.Create("https://www.googleapis.com/urlshortener/v1/url");
httpWebRequest.ContentType = "application/json";
httpWebRequest.Method = "POST";
using (var streamWriter = new StreamWriter(httpWebRequest.GetRequestStream()))
{
string json = "{\"longUrl\":\"http://www.google.com/\"}";
Console.WriteLine(json);
streamWriter.Write(json);
}
var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();
using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
{
var responseText = streamReader.ReadToEnd();
Console.WriteLine(responseText);
}
Console.Read();
and it worked fine, and returned everything OK, but when I try to do it on a Windows Phone App like this:
private void button1_Click(object sender, RoutedEventArgs e)
{
testConnection();
}
private void testConnection()
{
if (!NetworkInterface.GetIsNetworkAvailable())
MessageBox.Show("There's no internet connection, please reconnect to the internet and try again");
else
{
var req = (HttpWebRequest)WebRequest.Create("https://www.googleapis.com/urlshortener/v1/url");
req.ContentType = "application/json";
req.Method = "POST";
req.BeginGetRequestStream(new AsyncCallback(GetRequestStreamCallback), req);
textBlock2.Text = "Done";
}
}
void GetRequestStreamCallback(IAsyncResult asynchronousResult)
{
HttpWebRequest webRequest = (HttpWebRequest)asynchronousResult.AsyncState;
// End the stream request operation
Stream postStream = webRequest.EndGetRequestStream(asynchronousResult);
// Create the post data
// Demo POST data:
string postData = "http://www.google.com";
byte[] byteArray = Encoding.Unicode.GetBytes(postData);
// Add the post data to the web request
postStream.Write(byteArray, 0, byteArray.Length);
postStream.Close();
// Start the web request
webRequest.BeginGetResponse(new AsyncCallback(GetResponseCallback), webRequest);
}
void GetResponseCallback(IAsyncResult asynchronousResult)
{
try
{
HttpWebRequest webRequest = (HttpWebRequest)asynchronousResult.AsyncState;
HttpWebResponse response;
// End the get response operation
response = (HttpWebResponse)webRequest.EndGetResponse(asynchronousResult);
Stream streamResponse = response.GetResponseStream();
StreamReader streamReader = new StreamReader(streamResponse);
textBlock1.Text= streamReader.ReadToEnd();
streamResponse.Close();
streamReader.Close();
response.Close();
}
catch (WebException e)
{
}
}
The code always goes to the catch of the try method and gives "not found" error.
There is a known issue with SSL and not-trusted certificates. Connection to a web site with SSL that require ClientCertificates is not supported in the current Windows Phone 7 application model (Only BasicAuthentication is supported). You can read about the same problem here: http://forums.create.msdn.com/forums/p/65076/398730.aspx
I had a similar issue (which makes sense since I started out with this code as my example...) and when I changed the following code it started working to the point where I could progress forward again.
... from:
byte[] byteArray = Encoding.Unicode.GetBytes(postData);
... to (the equivalent of):
byte[] byteArray = Encoding.UTF8.GetBytes(postData);

Google OAuth2.0 - Windows phone 7

Experts,
I'm new to OAuth,
I'm writing an small App in windows Phone 7, I'm using OAuth2 for google contacts, I need to get the initial URL API (1) to get the Token
1) https://accounts.google.com/o/oauth2/auth?response_type=code&scope=https://www.google.com/m8/feeds/&redirect_uri=REDIRECT_URI&client_id=CLIENT_ID&hl=en-US&from_login=1&as=NEW_AS&pli=1
I got the success code, and when I'm trying to use this
https://www.google.com/m8/feeds/contacts/default/full?access_token=TOKEN_CODE
but I'm getting 401 error back,
Can you please advice, what mistake i'm going.
I've taken Twitter OAuth example as base, and doing modifications.
CODE
var uri = new Uri(url);
var request = BuildOAuthWebRequest(url, null);
MakeGetRequest(callback, request);
private static HttpWebRequest BuildOAuthWebRequest( string url, string realm)
{
var header = new StringBuilder();
var request = (HttpWebRequest)WebRequest.Create(url);
return request;
}
private static void MakeGetRequest(EventHandler<OAuthEventArgs> callback, HttpWebRequest request)
{
var asyncState = request.BeginGetResponse(new AsyncCallback((asyncRes) =>
{
HttpWebResponse response = null;
try
{
//request has returned
response = (HttpWebResponse)request.EndGetResponse(asyncRes);
if (response.StatusCode == HttpStatusCode.OK)
{
using (StreamReader sr = new StreamReader(response.GetResponseStream()))
{
var token = sr.ReadToEnd();
callback(null, new OAuthEventArgs() { Response = token });
}
}
}
catch (WebException we)
{
string t = new StreamReader(we.Response.GetResponseStream()).ReadToEnd();
callback(null, new OAuthEventArgs() { Error = we, ErrorMessage = t, IsError = true });
}
catch (Exception e)
{
callback(null, new OAuthEventArgs() { Error = e, ErrorMessage = e.Message, IsError = true });
}
finally
{
if (response != null)
response.Close();
}
}), null);
}

HttpWebRequest.EndGetResponse throws a NotSupportedException in Windows Phone 7

in a Silverlight-Windows Phone 7-project I am creating an HttpWebRequest, get the RequestStream, write something into the Stream and try to get the response, but I always get a NotSupportedException:
"System.Net.Browser.OHWRAsyncResult.AsyncWaitHandle threw an exception of type 'System.NotSupportedException'
My production code is far more complicated, but I can narrow it down to this small piece of code:
public class HttpUploadHelper
{
private HttpWebRequest request;
private RequestState state = new RequestState();
public HttpUploadHelper(string url)
{
this.request = WebRequest.Create(url) as HttpWebRequest;
state.Request = request;
}
public void Execute()
{
request.Method = "POST";
this.request.BeginGetRequestStream(
new AsyncCallback(BeginRequest), state);
}
private void BeginRequest(IAsyncResult ar)
{
Stream stream = state.Request.EndGetRequestStream(ar);
state.Request.BeginGetResponse(
new AsyncCallback(BeginResponse), state);
}
private void BeginResponse(IAsyncResult ar)
{
// BOOM: NotSupportedException was unhandled;
// {System.Net.Browser.OHWRAsyncResult}
// AsyncWaitHandle = 'ar.AsyncWaitHandle' threw an
// exception of type 'System.NotSupportedException'
HttpWebResponse response = state.Request.EndGetResponse(ar) as HttpWebResponse;
Debug.WriteLine(response.StatusCode);
}
}
public class RequestState
{
public WebRequest Request;
}
}
Does anybody know what is wrong with this code?
The NotSupportedException can be thrown when the request stream isn't closed before the call to EndGetResponse. The WebRequest stream is still open and sending data to the server when you're attempting to get the response. Since stream implements the IDisposable interface, a simple solution is to wrap your code using the request stream in a using block:
private void BeginRequest(IAsyncResult ar)
{
using (Stream stream = request.EndGetRequestStream(ar))
{
//write to stream in here.
}
state.Request.BeginGetResponse(
new AsyncCallback(BeginResponse), state);
}
The using block will ensure that the stream is closed before you attempt to get the response from the web server.
The issue is with how you're dealing with the accessing the original requests in the callback from BeginGetResponse.
Rather than holding a reference ot the state, get a reference back to the original request with:
var request = (HttpWebRequest)asynchronousResult.AsyncState;
Have a look at this very basic (but working) example of implementing logging in by posting email and password credentials to a website.
public static string Email;
public static string Password;
private void LoginClick(object sender, RoutedEventArgs e)
{
Email = enteredEmailAddress.Text.Trim().ToLower();
Password = enteredPassword.Password;
var request = (HttpWebRequest)WebRequest.Create(App.Config.ServerUris.Login);
request.ContentType = "application/x-www-form-urlencoded";
request.Method = "POST";
request.BeginGetRequestStream(ReadCallback, request);
}
private void ReadCallback(IAsyncResult asynchronousResult)
{
var request = (HttpWebRequest)asynchronousResult.AsyncState;
using (var postStream = request.EndGetRequestStream(asynchronousResult))
{
using (var memStream = new MemoryStream())
{
var content = string.Format("Password={0}&Email={1}",
HttpUtility.UrlEncode(Password),
HttpUtility.UrlEncode(Email));
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);
}
}
request.BeginGetResponse(ResponseCallback, request);
}
private void ResponseCallback(IAsyncResult asynchronousResult)
{
var request = (HttpWebRequest)asynchronousResult.AsyncState;
using (var resp = (HttpWebResponse)request.EndGetResponse(asynchronousResult))
{
using (var streamResponse = resp.GetResponseStream())
{
using (var streamRead = new StreamReader(streamResponse))
{
string responseString = streamRead.ReadToEnd();
// do something with responseString to check if login was successful
}
}
}
}
NotSupportedException can also be thrown when string url is too long. I had messed up and attached post data to url instead of post body. When the data was short, it worked just fine, but once it grew too large - EndGetResponse crashed.
Change this:
state.Request.BeginGetResponse(
new AsyncCallback(BeginResponse), state);
To this:
state.Request.BeginGetResponse(BeginResponse, state);

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