C# WP8 async HttpWebRequest Post with xml request message - c#

i've been reading here for quite a long time, but in this case i'm not getting any further.
I'm rather new to Windows Phone development and facing the following problem.
I'm calling a webservice were I have to post a xml request message. I've got the code working in regular c# (see code below)
private static string WebRequestPostData(string url, string postData)
{
System.Net.WebRequest req = System.Net.WebRequest.Create(url);
req.ContentType = "text/xml";
req.Method = "POST";
byte[] bytes = System.Text.Encoding.ASCII.GetBytes(postData);
req.ContentLength = bytes.Length;
using (Stream os = req.GetRequestStream())
{
os.Write(bytes, 0, bytes.Length);
}
using (System.Net.WebResponse resp = req.GetResponse())
{
if (resp == null) return null;
using (System.IO.StreamReader sr = new System.IO.StreamReader(resp.GetResponseStream()))
{
return sr.ReadToEnd().Trim();
}
}
}
But for Windows Phone (8) development it needs to be async. After searching the web, and trying the various samples given here I came to the following code:
private async void DoCallWS()
{
string url = "<my_url>";
// HTTP web request
var httpWebRequest = (HttpWebRequest)WebRequest.Create(url);
httpWebRequest.ContentType = "text/xml";
httpWebRequest.Method = "POST";
// Write the request Asynchronously
using (var stream = await Task.Factory.FromAsync<Stream>(httpWebRequest.BeginGetRequestStream,
httpWebRequest.EndGetRequestStream, null))
{
string requestXml = "<my_request_xml>";
// convert request to byte array
byte[] requestAsBytes = Encoding.UTF8.GetBytes(requestXml);
// Write the bytes to the stream
await stream.WriteAsync(requestAsBytes , 0, requestAsBytes .Length);
stream.Position = 0;
using (StreamReader reader = new StreamReader(stream, Encoding.UTF8))
{
//return reader.ReadToEnd();
string result = reader.ReadToEnd();
}
}
}
The string result has the value of my request xml message i'm trying to sent....
I'm aware that async void methodes are not preferred but i will fix that later.
I've also tried to following the solution as described by Matthias Shapiro (http://matthiasshapiro.com/2012/12/10/window-8-win-phone-code-sharing-httpwebrequest-getresponseasync/) but that caused the code to crash
Please point me in the right direction :)
Thnx Frank

What you're doing is only writing to the request stream. You're missing the code which reads from the response.
The reason you're getting back your request xml is that you reset the request stream and read from that exact stream.
Your method should look as follows:
private async Task DoCallWSAsync()
{
string url = "<my_url>";
// HTTP web request
var httpWebRequest = (HttpWebRequest)WebRequest.Create(url);
httpWebRequest.ContentType = "text/xml";
httpWebRequest.Method = "POST";
// Write the request Asynchronously
using (var stream = await Task.Factory.FromAsync<Stream>(httpWebRequest.BeginGetRequestStream,
httpWebRequest.EndGetRequestStream, null))
{
string requestXml = "<my_request_xml>";
// convert request to byte array
byte[] requestAsBytes = Encoding.UTF8.GetBytes(requestXml);
// Write the bytes to the stream
await stream.WriteAsync(requestAsBytes , 0, requestAsBytes .Length);
}
using (WebResponse responseObject = await Task<WebResponse>.Factory.FromAsync(httpWebRequest.BeginGetResponse, httpWebRequest.EndGetResponse, httpWebRequest))
{
var responseStream = responseObject.GetResponseStream();
var sr = new StreamReader(responseStream);
string received = await sr.ReadToEndAsync();
return received;
}
}

Related

Getting content from httpwebresponse exception

My remote server is throwing a web exception as bad request. But I know there is more information included in the error than what I get. If I look at the details from the exception it does not list the actual content of the response. I can see the content-type, content-length and content-encoding only. If I run this same message through another library (such as restsharp) I will see detailed exception information from the remote server. How can I get more details from the response since I know the remote server is sending them?
static string getXMLString(string xmlContent, string url)
{
//string Url;
string sResult;
//Url = ConfigurationManager.AppSettings["UserURl"] + url;
var httpWebRequest = (HttpWebRequest)WebRequest.Create(url);
httpWebRequest.ContentType = "application/xml";
httpWebRequest.Method = "POST";
using (var streamWriter = new StreamWriter(httpWebRequest.GetRequestStream()))
{
streamWriter.Write(xmlContent);
streamWriter.Flush();
streamWriter.Close();
var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();
using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
{
var result = streamReader.ReadToEnd();
sResult = result;
}
}
return sResult;
}
EDIT : Have you tried with a simple try-catch to see if you can get more details ?
try
{
var response = (HttpWebResponse)(request.GetResponse());
}
catch(Exception ex)
{
var response = (HttpWebResponse)ex.Response;
}
In my recherches in an answer for you, I noticed that in code there was something about encoding, that you didn't specified. Look here for exemple with such code.
var encoding = ASCIIEncoding.ASCII;
using (var reader = new System.IO.StreamReader(response.GetResponseStream(), encoding))
{
string responseText = reader.ReadToEnd();
}
Or here, in the doc, also.
// Creates an HttpWebRequest with the specified URL.
HttpWebRequest myHttpWebRequest = (HttpWebRequest)WebRequest.Create(url);
// Sends the HttpWebRequest and waits for the response.
HttpWebResponse myHttpWebResponse = (HttpWebResponse)myHttpWebRequest.GetResponse();
// Gets the stream associated with the response.
Stream receiveStream = myHttpWebResponse.GetResponseStream();
Encoding encode = System.Text.Encoding.GetEncoding("utf-8");
// Pipes the stream to a higher level stream reader with the required encoding format.
StreamReader readStream = new StreamReader( receiveStream, encode );
Console.WriteLine("\r\nResponse stream received.");
Have you tried with such ?

ContentLength error for Request Stream in C#

I'm trying to get some data back from rest WS in C# but I'm getting this error:
You must write ContentLength bytes to the request stream before calling [Begin]GetResponse.
This is the code I'm trying to use:
var json = new JavaScriptSerializer().Serialize(order);
string jsonResponseToString = "";
HttpWebRequest request =
(HttpWebRequest)WebRequest.Create("https://myurl.com");
request.Method = "POST";
System.Text.UTF8Encoding encoding = new System.Text.UTF8Encoding();
Byte[] byteArray = encoding.GetBytes(json);
request.ContentLength = byteArray.Length;
request.ContentType = #"application/json";
try
{
using (var response = (HttpWebResponse)request.GetResponse())
{
Stream str = response.GetResponseStream();
var sr = new StreamReader(str, encoding);
jsonResponseToString = sr.ReadToEnd();
var result = new OrderResult();
result = new JavaScriptSerializer().Deserialize<OrderResult>(jsonResponseToString);
if (str != null)
{
str.Flush();
str.Close();
}
}
}
catch (WebException ex)
{
//
}
The error is happening on this line:
using (var response = (HttpWebResponse)request.GetResponse())
How can I solve this, am I doing something wrong?
As the error is trying to tell you, you need to write your bytes to the request before you can send it.
Call GetRequestStream() and write your bytes.

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();
}
}

Httpwebrequest--POST method using text file

I am trying to replicate a Couch database using .NET classes instead of a curl command line. I have never used WebRequest or Httpwebrequest before, but I am attempting to use them to make a post request with the script below.
Here is the JSON script for couchdb replication(I know this works):
{ ""_id"":"database_replicate8/7/12", "source":sourcedb, ""target"":"targetDB", ""create_target"":true, ""user_ctx"": { ""roles"": ["myrole"] } }
The above script is put into a text file, sourcefile.txt. I want to take this line and put it in a POST web request using .NET functionality.
After looking into it, I chose to use the httpwebrequest class. Below is what I have so far--I got this from http://msdn.microsoft.com/en-us/library/debx8sh9.aspx
HttpWebRequest bob = (HttpWebRequest)WebRequest.Create("sourceDBURL");
bob.Method = "POST";
bob.ContentType = "application/json";
byte[] bytearray = File.ReadAllBytes(#"sourcefile.txt");
Stream datastream = bob.GetRequestStream();
datastream.Write(bytearray, 0, bytearray.Length);
datastream.Close();
Am I going about this correctly? I am relatively new to web technologies and still learning how http calls work.
Here is a method I use for creating POST requests:
private static HttpWebRequest createNewPostRequest(string apikey, string secretkey, string endpoint)
{
HttpWebRequest request = WebRequest.Create(endpoint) as HttpWebRequest;
request.Proxy = null;
request.Method = "POST";
//Specify the xml/Json content types that are acceptable.
request.ContentType = "application/xml";
request.Accept = "application/xml";
//Attach authorization information
request.Headers.Add("Authorization", apikey);
request.Headers.Add("Secretkey", secretkey);
return request;
}
Within my main method I call it like this:
HttpWebRequest request = createNewPostRequest(apikey, secretkey, endpoint);
and I then pass my data to the method like this:
string requestBody = SerializeToString(requestObj);
byte[] byteStr = Encoding.UTF8.GetBytes(requestBody);
request.ContentLength = byteStr.Length;
using (Stream stream = request.GetRequestStream())
{
stream.Write(byteStr, 0, byteStr.Length);
}
//Parse the response
using (HttpWebResponse response = request.GetResponse() as HttpWebResponse)
{
//Business error
if (response.StatusCode != HttpStatusCode.OK)
{
Console.WriteLine(string.Format("Error: response status code is{0}, at time:{1}", response.StatusCode, DateTime.Now.ToString()));
return "error";
}
else if (response.StatusCode == HttpStatusCode.OK)//Success
{
using (Stream respStream = response.GetResponseStream())
{
XmlSerializer serializer = new XmlSerializer(typeof(SubmitReportResponse));
reportReq = serializer.Deserialize(respStream) as SubmitReportResponse;
}
}
...
In my case I serialize/deserialize my body from a class - you will need to alter this to use your text file. If you want an easy drop in solution, then change the SerializetoString method to a method that loads your text file to a string.

C# Xml in Http Post Request Message Body

I am looking for an example of how, in C#, to put a xml document in the message body of a http request and then parse the response. I've read the documentation but I would just like to see an example if there's one available. Does anyone have a example?
thanks
private static string WebRequestPostData(string url, string postData)
{
System.Net.WebRequest req = System.Net.WebRequest.Create(url);
req.ContentType = "text/xml";
req.Method = "POST";
byte[] bytes = System.Text.Encoding.ASCII.GetBytes(postData);
req.ContentLength = bytes.Length;
using (Stream os = req.GetRequestStream())
{
os.Write(bytes, 0, bytes.Length);
}
using (System.Net.WebResponse resp = req.GetResponse())
{
if (resp == null) return null;
using (System.IO.StreamReader sr = new System.IO.StreamReader(resp.GetResponseStream()))
{
return sr.ReadToEnd().Trim();
}
}
}
You should use the WebRequest class.
There is an annotated sample available here to send data:
http://msdn.microsoft.com/en-us/library/debx8sh9.aspx

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