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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 ?

Call Genderize.io API From C#

I'm trying to call http://genderize.io/ , but i'm getting an error from .NET saying:
{"You must provide a request body if you set ContentLength>0 or SendChunked==true. Do this by calling [Begin]GetRequestStream before [Begin]GetResponse."}
How would I call this web service "http://api.genderize.io/?name=peter" from C# and get a JSON string back?
HttpWebRequest request;
string postData = "name=peter"
URL = "http://api.genderize.io/?"
Uri uri = new Uri(URL + postData);
request = (HttpWebRequest)WebRequest.Create(uri);
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
request.ContentLength = postData.Length;
request.AllowAutoRedirect = true;
UTF8Encoding enc = new UTF8Encoding();
string result = string.Empty;
HttpWebResponse Response;
try
{
using (Response = (HttpWebResponse)request.GetResponse())
{
using (Stream responseStream = Response.GetResponseStream())
{
using (StreamReader readStream = new StreamReader(responseStream, Encoding.UTF8))
{
return readStream.ReadToEnd();
}
}
}
}
catch (Exception ex)
{
Debug.WriteLine("Error: " + ex.Message);
throw ex;
}

You are making the call to the service using POST method, reading through the comments area in http://genderize.io/ the author states that only GET method requests are allowed.
Stroemgren: Yes, this is confirmed. Only HTTP GET request are allowed.
This answer probably would be better as a comment, but I don't have enough reputation :(

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();
}
}

The remote server returned an error: (405) Method Not Allowed. WCF REST Service

This question is already asked elsewhere but those things are not the solutions for my issue.
This is my service
[WebInvoke(UriTemplate = "", Method = "POST")]
public SampleItem Create(SampleItem instance)
{
// TODO: Add the new instance of SampleItem to the collection
// throw new NotImplementedException();
return new SampleItem();
}
I have this code to call the above service
XElement data = new XElement("SampleItem",
new XElement("Id", "2"),
new XElement("StringValue", "sdddsdssd")
);
System.IO.MemoryStream dataSream1 = new MemoryStream();
data.Save(dataSream1);
HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://localhost:2517/Service1/Create");
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
// You need to know length and it has to be set before you access request stream
request.ContentLength = dataSream1.Length;
using (Stream requestStream = request.GetRequestStream())
{
dataSream1.CopyTo(requestStream);
byte[] bytes = dataSream1.ToArray();
requestStream.Write(bytes, 0, Convert.ToInt16(dataSream1.Length));
requestStream.Close();
}
WebResponse response = request.GetResponse();
I get an exception at the last line:
The remote server returned an error: (405) Method Not Allowed. Not sure why this is happening i tried changing the host from VS Server to IIS also but no change in result. Let me know if u need more information

First thing is to know the exact URL for your REST Service. Since you have specified http://localhost:2517/Service1/Create now just try to open the same URL from IE and you should get method not allowed as your Create Method is defined for WebInvoke and IE does a WebGet.
Now make sure that you have the SampleItem in your client app defined in the same namespace on your server or make sure that the xml string you are building has the appropriate namespace for the service to identify that the xml string of sample object can be deserialized back to the object on server.
I have the SampleItem defined on my server as shown below:
namespace SampleApp
{
public class SampleItem
{
public int Id { get; set; }
public string StringValue { get; set; }
}
}
The xml string corresponding to my SampleItem is as below:
<SampleItem xmlns="http://schemas.datacontract.org/2004/07/SampleApp" xmlns:i="http://www.w3.org/2001/XMLSchema-instance"><Id>6</Id><StringValue>from client testing</StringValue></SampleItem>
Now i use the below method to perform a POST to the REST service :
private string UseHttpWebApproach<T>(string serviceUrl, string resourceUrl, string method, T requestBody)
{
string responseMessage = null;
var request = WebRequest.Create(string.Concat(serviceUrl, resourceUrl)) as HttpWebRequest;
if (request != null)
{
request.ContentType = "application/xml";
request.Method = method;
}
//var objContent = HttpContentExtensions.CreateDataContract(requestBody);
if(method == "POST" && requestBody != null)
{
byte[] requestBodyBytes = ToByteArrayUsingDataContractSer(requestBody);
request.ContentLength = requestBodyBytes.Length;
using (Stream postStream = request.GetRequestStream())
postStream.Write(requestBodyBytes, 0, requestBodyBytes.Length);
}
if (request != null)
{
var response = request.GetResponse() as HttpWebResponse;
if(response.StatusCode == HttpStatusCode.OK)
{
Stream responseStream = response.GetResponseStream();
if (responseStream != null)
{
var reader = new StreamReader(responseStream);
responseMessage = reader.ReadToEnd();
}
}
else
{
responseMessage = response.StatusDescription;
}
}
return responseMessage;
}
private static byte[] ToByteArrayUsingDataContractSer<T>(T requestBody)
{
byte[] bytes = null;
var serializer1 = new DataContractSerializer(typeof(T));
var ms1 = new MemoryStream();
serializer1.WriteObject(ms1, requestBody);
ms1.Position = 0;
var reader = new StreamReader(ms1);
bytes = ms1.ToArray();
return bytes;
}
Now i call the above method as shown:
SampleItem objSample = new SampleItem();
objSample.Id = 7;
objSample.StringValue = "from client testing";
string serviceBaseUrl = "http://localhost:2517/Service1";
string resourceUrl = "/Create";
string method="POST";
UseHttpWebApproach<SampleItem>(serviceBaseUrl, resourceUrl, method, objSample);
I have the SampleItem object defined in the client side as well. If you want to build the xml string on the client and pass then you can use the below method:
private string UseHttpWebApproach(string serviceUrl, string resourceUrl, string method, string xmlRequestBody)
{
string responseMessage = null;
var request = WebRequest.Create(string.Concat(serviceUrl, resourceUrl)) as HttpWebRequest;
if (request != null)
{
request.ContentType = "application/xml";
request.Method = method;
}
//var objContent = HttpContentExtensions.CreateDataContract(requestBody);
if(method == "POST" && requestBody != null)
{
byte[] requestBodyBytes = ASCIIEncoding.UTF8.GetBytes(xmlRequestBody.ToString());
request.ContentLength = requestBodyBytes.Length;
using (Stream postStream = request.GetRequestStream())
postStream.Write(requestBodyBytes, 0, requestBodyBytes.Length);
}
if (request != null)
{
var response = request.GetResponse() as HttpWebResponse;
if(response.StatusCode == HttpStatusCode.OK)
{
Stream responseStream = response.GetResponseStream();
if (responseStream != null)
{
var reader = new StreamReader(responseStream);
responseMessage = reader.ReadToEnd();
}
}
else
{
responseMessage = response.StatusDescription;
}
}
return responseMessage;
}
And the call to the above method would be as shown below:
string sample = "<SampleItem xmlns=\"http://schemas.datacontract.org/2004/07/XmlRestService\" xmlns:i=\"http://www.w3.org/2001/XMLSchema-instance\"><Id>6</Id><StringValue>from client testing</StringValue></SampleItem>";
string serviceBaseUrl = "http://localhost:2517/Service1";
string resourceUrl = "/Create";
string method="POST";
UseHttpWebApproach<string>(serviceBaseUrl, resourceUrl, method, sample);
NOTE: Just make sure that your URL is correct

Are you running WCF application for the first time?
run below command to register wcf.
"%WINDIR%\Microsoft.Net\Framework\v3.0\Windows Communication Foundation\ServiceModelReg.exe" -r

After spending 2 days on this, using VS 2010 .NET 4.0, IIS 7.5 WCF and REST with JSON ResponseWrapped, I finally cracked it by reading from "When investigating further..." here https://sites.google.com/site/wcfpandu/useful-links
The Web Service Client code generated file Reference.cs doesn't attribute the GET methods with [WebGet()], so attempts to POST them instead, hence the InvalidProtocol, 405 Method Not Allowed. Problem is though, this file is regenerated when ever you refresh the service reference, and you also need a dll reference to System.ServiceModel.Web, for the WebGet attribute.
So I've decided to manually edit the Reference.cs file, and keep a copy. Next time I refresh it, I'll merge my WebGet()s back in.
The way I see it, it's a bug with svcutil.exe not recognising that some of the service methods are GET and not just POST, even though the WSDL and HELP that the WCF IIS web service publishes, does understand which methods are POST and GET??? I've logged this issue with Microsoft Connect.

When it happened to me, I just simply added the word post
to the function name, and it solved my problem. maybe it will help some of you too.

In the case I came up against, there was yet another cause: the underlying code was attempting to do a WebDAV PUT. (This particular application was configurable to enable this feature if required; the feature was, unbeknownst to me, enabled, but the necessary web server environment was not set up.
Hopefully this may help someone else.

The issue I have fixed, because your service is secured by login credential with user name and password, try set up the user name and password on the request, it will be working. Good luck!

Help with simple restful post problem

I am new to restful services and I have been creating a series of simple console apps to better understand. I have a simlple service that I am trying to send data to but I keep getting a 400 bad request error. I know it has to be something simple I overlooked. Any help would be greatly appreciated. Thanks
//service contract
[OperationContract, WebInvoke(Method = "POST", UriTemplate = "Test")]
bool Test(string input);
//service
public bool Test(string input)
{
Console.Out.WriteLine("recieved [" + input + "]");
return true;
}
//host program
class Program
{
static void Main(string[] args)
{
Uri baseAddress = new Uri("http://localhost:8889/TestImage");
WebServiceHost host = new WebServiceHost(typeof(ImageTestService), baseAddress);
try
{
host.Open();
Console.Out.WriteLine("TestService hosted at {0}", baseAddress.ToString());
Console.Out.WriteLine("hit enter to terminate");
Console.In.ReadLine();
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
Console.ReadKey();
}
finally
{
if (host.State == CommunicationState.Faulted)
host.Abort();
else
host.Close();
}
}
}
//client program
// Create the web request
Uri address = new Uri("http://localhost:8889/TestImage/Test");
HttpWebRequest request = WebRequest.Create(address) as HttpWebRequest;
// Set type to POST
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
StringBuilder data = new StringBuilder();
data.Append("input=" + HttpUtility.UrlEncode("12345"));
// Create a byte array of the data we want to send
byte[] byteData = UTF8Encoding.UTF8.GetBytes(data.ToString());
// Set the content length in the request headers
request.ContentLength = byteData.Length;
// Write data
using (Stream postStream = request.GetRequestStream())
{
postStream.Write(byteData, 0, byteData.Length);
postStream.Close();
}
// Get response
using (HttpWebResponse response = request.GetResponse() as HttpWebResponse)
{
// Get the response stream
StreamReader reader = new StreamReader(response.GetResponseStream());
}

Not sure that is answers your question - but I have an extension method I have been using for form post:
public static HttpWebResponse DoFormPost(this HttpWebRequest request, string postVals, int timeoutSeconds)
{
request.Method = "POST";
request.Timeout = timeoutSeconds * 0x3e8;
request.ContentType = "application/x-www-form-urlencoded";
request.AllowAutoRedirect = false;
byte[] bytes = Encoding.UTF8.GetBytes(postVals);
request.ContentLength = bytes.Length;
using (Stream stream = request.GetRequestStream())
{
stream.Write(bytes, 0, bytes.Length);
}
return (HttpWebResponse)request.GetResponse();
}
Or since you tagged WCF, then there is also another similar question:
Getting an http 400 error on calling a restful wcf service using http post

Unfortunately, I'm not sure what's wrong with your code, it looks okay at first glance. I wonder if it's the UriTemplate that you're using. If your method is "Test" and the UriTemplate is "Test", you might need to call it with this URL (two "Test" strings):
Uri address = new Uri("http://localhost:8889/TestImage/Test/Test");
I believe the method name is part of the URL by default, so the template gets applied after that.
With HTTP errors, I use a tool called Fiddler to troubleshoot. If you can create a request that works with the Request Builder, it's just a matter of figuring out how to produce that request via your code.

The WCF service you are calling is expecting the string you are passing to be serialized in XML!
The following has worked for me in the past:
string body = "foo";
string postData = #"<string xmlns='http://schemas.microsoft.com/2003/10/Serialization/'><![CDATA[" + body + "]]></string>";