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);
Related
I am developing a mobile application using Xamarin. This makes it so I cannot call webRequest.ContentLength = 0.
Here is how I am attempting to post:
Client calls:
await new AssetEndpoint().UpdateStatus(Authentication, CurrentAsset, ApprovalStatuses[0]);
AssetEndpoint.UpdateStatus:
public Task UpdateStatus(Authentication auth, Asset asset, ApprovalStatus newStatus)
{
return PostResponseAsync(auth, string.Format(
ApiUpdateStatus, asset.UID, newStatus.Id));
}
Endpoint.PostResponseAsync:
protected async Task<string> PostResponseAsync(Authentication auth, string apiCall)
{
var request = WebRequest.Create(string.Concat(BaseUriPath, apiCall)) as HttpWebRequest;
request.ContentType = "application/json";
request.Method = method;
request.Headers["Authorization"] = string.Concat("bearer ", auth.Token.Value);
var response = await request.GetResponseAsync().ConfigureAwait(false);
using (var reader = new StreamReader(response.GetResponseStream()))
{
return await reader.ReadToEndAsync();
}
}
So I do go about fixing this error? I cannot seem to figure out how to set the content length.
It can be the problem in Xamarin version you are using:
http://forums.xamarin.com/discussion/comment/58076#Comment_58076
public class RestClientTest
{
public static async Task<string> Login()
{
try
{
var request = WebRequest.CreateHttp(path);
request.Headers["Username"] = "xxxxxxxxx";
request.Headers["Password"] = "xxxxxxxxxxx";
request.ContentType = "application/json";
request.Method = "POST";
byte[] byteArray = new byte[] { 0x31, 0x32, 0x33, 0x34, 0x35 };
using (Stream dataStream = await request.GetRequestStreamAsync())
{
await dataStream.WriteAsync(byteArray, 0, byteArray.Length);
}
var response = await request.GetResponseAsync().ConfigureAwait(false);
using (var reader = new StreamReader(response.GetResponseStream()))
{
string resp = await reader.ReadToEndAsync();
return resp;
}
}
catch (Exception ex)
{
return "Error";
}
}
}
If that doesn't work for you I can provide HttpClient sample if you want to try. Without knowing what you are posting I cannot help more. I also tested this code without sending any data in the body and it works too.
I have a Windows Phone Application and I I am trying to post data in JSON format to a WCF application. Although the connection is made, the server returns with a custom message with
This is the C# code:
ReportSightingRequest.Instance.Source = Source.IPhone;
var jsonData = JsonConvert.SerializeObject(ReportSightingRequest.Instance);
var uri = new Uri("urlGoesHere", UriKind.Absolute);
var request = (HttpWebRequest)WebRequest.Create(uri);
request.Method = "POST";
request.ContentType = "application/json";
request.ContentLength = jsonData.Length;
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();
}
}
}
This is the WCF Interface:
[OperationContract]
[WebInvoke(Method = "POST", RequestFormat = WebMessageFormat.Json, ResponseFormat = WebMessageFormat.Json)]
[Description("Description.")]
Response.Response ReportSighting(ReportSightingRequest sighting);
This is the implementation:
public Response ReportSighting(ReportSightingRequest sightingRequest)
{
var response = new Response();
if (sightingRequest == null || sightingRequest.TypeId == null)
{
response.Status = ResponseStatus.InvalidArguments;
response.Message = "Request is null or no type has been supplied.";
return response;
}
...
}
When I call the ReportSighting method form the phone, I get a "Request is null or no type has been supplied" message. The strange thing is that I AM sending a TypeId and the sightingRequest object on the WP8 side is definitely not null when i'm sending it. When I put a breakpoint on the jsonData, it has everything in it. The ReportSightingRequest object too is exactly the same as the ReportSightingRequest in the WCF application.
It almost feels like that the object isn't being serialized. That's the only thing I can think of.
Does anyone have any ideas/suggestions?
Update
I've noticed that i'm actually not sending over the object. Shawn Kendrot's Answer seems to make sense but when I integrate his code, it returns with a Not Found error.
Update
The following code works in a Console App:
var jsonData = "a hard coded JSON string here";
var uri = new Uri("a url goes here", UriKind.Absolute);
var webRequest = (HttpWebRequest)WebRequest.Create(uri);
webRequest.Method = "POST";
webRequest.ContentType = "application/json; charset=utf-8";
webRequest.ContentLength = jsonData.Length;
webRequest.BeginGetRequestStream(ar =>
{
try
{
using (var os = webRequest.EndGetRequestStream(ar))
{
var postData = Encoding.UTF8.GetBytes(jsonData);
os.Write(postData, 0, postData.Length);
}
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
webRequest.BeginGetResponse(
ar2 =>
{
try
{
using (var response = webRequest.EndGetResponse(ar2))
using (var reader = new StreamReader(response.GetResponseStream()))
{
var received = reader.ReadToEnd();
//Console.WriteLine(received);
}
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
}, null);
}, null);
Update
I have changed my code in WP8 to match that of Shawn Kendrot's solution. The problem which I am facing here is that I get a Not Found error message:
webRequest.BeginGetRequestStream(ar =>
{
try
{
using (var os = webRequest.EndGetRequestStream(ar))
{
var postData = Encoding.UTF8.GetBytes(jsonData);
os.Write(postData, 0, postData.Length);
}
}
catch (Exception ex)
{
MessageBox.Show("Unsuccessful");
}
webRequest.BeginGetResponse(
ar2 =>
{
try
{
using (var response = webRequest.EndGetResponse(ar2))
using (var reader = new StreamReader(response.GetResponseStream()))
{
var received = reader.ReadToEnd();
}
}
catch (Exception ex)
{
MessageBox.Show("Unsuccessful");
}
}, null);
}, null);
I get a:
{System.UnauthorizedAccessException: Invalid cross-thread access.
at MS.Internal.XcpImports.CheckThread()
at MS.Internal.XcpImports.MessageBox_ShowCore(String messageBoxText, String caption, UInt32 type)
at System.Windows.MessageBox.ShowCore(String messageBoxText, String caption, MessageBoxButton button)
at System.Windows.MessageBox.Show(String messageBoxText)
at Notify.Logic.WebServices.<>c_DisplayClass2.b_1(IAsyncResult ar2)
at System.Net.Browser.ClientHttpWebRequest.<>c_DisplayClass1d.b_1b(Object state2)}
When I try to do `MessageBox.Show(ex.Message);
Update
I have fixed the issue with the MessageBox.Show error message.
The webRequest.Headers object has the following:
{Content-Type: application/json; charset=utf-8;}
Your sightingRequest is null because you are not sending any data. To send data using a WebRequest, you need to use the BeginGetRequestStream method. This method allows you to package the data.
var webRequest= (HttpWebRequest)WebRequest.Create(uri);
webRequest.Method = "POST";
webRequest.ContentType = "application/json";
webRequest.ContentLength = jsonData.Length;
webRequest.BeginGetRequestStream(ar =>
{
try
{
using (Stream os = webRequest.EndGetRequestStream(ar))
{
var postData = Encoding.UTF8.GetBytes(jsonData);
os.Write(postData, 0, postData.Length);
}
}
catch (Exception ex)
{
// Do something, exit out, etc.
}
webRequest.BeginGetResponse(
ar2 =>
{
try
{
using (var response = webRequest.EndGetResponse(ar2))
using (var reader = new StreamReader(response.GetResponseStream()))
{
string received = reader.ReadToEnd();
}
}
catch (Exception ex)
{
// Do something, exit out, etc.
}
}, null);
}, null);
I get warning on responseStream in following function:
private static string GetResponseString(WebResponse response)
{
using (var responseStream = response.GetResponseStream())
{
if (responseStream != null)
{
using (var responseReader = new StreamReader(responseStream))
{
var strResponse = responseReader.ReadToEnd();
return strResponse;
}
}
}
return string.Empty;
}
I call this function from places like like this one:
var request = (HttpWebRequest)WebRequest.Create(Uri);
request.Headers.Add("Authorization", "GoogleLogin auth=" + this.SecurityToken);
request.ContentType = "application/x-www-form-urlencoded";
request.Method = "POST";
request.Timeout = 5000;
// build the post string
var postString = new StringBuilder();
postString.AppendFormat("registration_id={0}", recipientId);
postString.AppendFormat("&data.payload={0}", message);
postString.AppendFormat("&collapse_key={0}", collapseKey);
// write the post-string as a byte array
var requestData = Encoding.ASCII.GetBytes(postString.ToString());
request.ContentLength = requestData.Length;
var requestStream = request.GetRequestStream();
requestStream.Write(requestData, 0, requestData.Length);
requestStream.Close();
// Do the actual request and read the response stream
try
{
var response = request.GetResponse();
var responseString = GetResponseString(response);
response.Close();
return responseString.Contains("id=")
? SendStatus.Ok
: GetSendStatusFromResponse(responseString);
}
catch (WebException ex)
{
var webResponse = (HttpWebResponse)ex.Response;
if (webResponse != null)
{
if (webResponse.StatusCode.Equals(HttpStatusCode.Unauthorized))
{
return SendStatus.Unauthorized;
}
if (webResponse.StatusCode.Equals(HttpStatusCode.ServiceUnavailable))
{
return SendStatus.ServiceUnavailable;
}
}
this.LoggerService.Log(null, ex);
return SendStatus.GeneralException;
}
StreamReader takes ownership of the stream passed to it in the constructor call in the sense that it will call Dispose on it when the StreamReader itself is closed - hence it will already be disposed when the outer Using statement attempts to dispose of it.
I am new to Windows Phone 7 application development. I am trying to call a URL in my program using POST method which takes some parameters. After the successful post I am supposed to get the response in JSON format. But I am not getting the response. The code I am using is:
public void Submit()
{
// Prepare web request...
HttpWebRequest myRequest = (HttpWebRequest)WebRequest.Create(new Uri(someUrl, UriKind.Absolute));
myRequest.Method = "POST";
myRequest.ContentType = string.Format("multipart/form-data; boundary={0}", boundary);
myRequest.BeginGetRequestStream(new AsyncCallback(GetRequestStreamCallback), myRequest);
}
public string url { get; set; }
private Dictionary<string, string> _parameters = new Dictionary<string, string>();
public Dictionary<string, string> parameters
{
get { return _parameters; }
set { _parameters = value; }
}
string boundary = "----------" + DateTime.Now.Ticks.ToString();
private void GetRequestStreamCallback(IAsyncResult asynchronousResult)
{
HttpWebRequest request = (HttpWebRequest)asynchronousResult.AsyncState;
Stream postStream = request.EndGetRequestStream(asynchronousResult);
parameters.Add("userid", "0");
parameters.Add("locationid", "0");
writeMultipartObject(postStream, parameters);
postStream.Close();
request.BeginGetResponse(new AsyncCallback(GetResponseCallback), request);
}
private void GetResponseCallback(IAsyncResult asynchronousResult)
{
HttpWebRequest request = (HttpWebRequest)asynchronousResult.AsyncState;
HttpWebResponse response = (HttpWebResponse)request.EndGetResponse(asynchronousResult);
Stream streamResponse = response.GetResponseStream();
StreamReader streamRead = new StreamReader(streamResponse);
streamResponse.Close();
streamRead.Close();
// Release the HttpWebResponse
response.Close();
}
public void writeMultipartObject(Stream stream, object data)
{
StreamWriter writer = new StreamWriter(stream);
if (data != null)
{
foreach (var entry in data as Dictionary<string, string>)
{
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());
}
}
}
I cannot find what the real problem is. Anybody out there to help me out?
Maybe not a 'real' answer, but I always use: http://postclient.codeplex.com/ when dealing with Posts. This just to be sure I don't write any faults with the Request code.
Just give it a try.
This example come from http://northernlights.codeplex.com
/// <summary>
/// Send error report (exception) to HTTP endpoint.
/// </summary>
/// <param name="uri">The Endpoint to report to.</param>
/// <param name="exception">Exception to send.</param>
public void SendExceptionToHttpEndpoint(string uri, ExceptionContainer exception)
{
if (!this.AllowAnonymousHttpReporting)
{
return;
}
try
{
HttpWebRequest webRequest = (HttpWebRequest)WebRequest.Create(uri);
webRequest.Method = "POST";
webRequest.ContentType = "application/x-www-form-urlencoded";
webRequest.BeginGetRequestStream(
r =>
{
try
{
HttpWebRequest request1 = (HttpWebRequest)r.AsyncState;
Stream postStream = request1.EndGetRequestStream(r);
string info = string.Format("{0}{1}{2}{1}AppVersion: {3}{1}", exception.Message, Environment.NewLine, exception.StackTrace, exception.AppVersion);
string postData = "&exception=" + HttpUtility.UrlEncode(info);
byte[] byteArray = Encoding.UTF8.GetBytes(postData);
postStream.Write(byteArray, 0, byteArray.Length);
postStream.Close();
request1.BeginGetResponse(
s =>
{
try
{
HttpWebRequest request2 = (HttpWebRequest)s.AsyncState;
HttpWebResponse response = (HttpWebResponse)request2.EndGetResponse(s);
Stream streamResponse = response.GetResponseStream();
StreamReader streamReader = new StreamReader(streamResponse);
string response2 = streamReader.ReadToEnd();
streamResponse.Close();
streamReader.Close();
response.Close();
}
catch
{
}
},
request1);
}
catch
{
}
},
webRequest);
}
catch
{
}
}
It shows you how to post.
WP7 ships with the "Reactive Extensions" that is helpful with asynch interactions in general. This sample http://wp7guide.codeplex.com shows how to use it for HTTP Posts (and other things)
Caveat: the sample is for a rather advanced app, and is meant to show many other things like unit testing, using the MVVM pattern, etc. It might be more sophisticated than what you need.
I got the solution as:
{
Dictionary<string, object> param = new Dictionary<string, object>();
param.Add(DataHolder.USER_ID, "0");
param.Add(DataHolder.DEFAULT_LOCATION_ID, "0");
PostClient proxy = new PostClient(param);
proxy.DownloadStringCompleted += new PostClient.DownloadStringCompletedHandler(proxy_DownloadStringCompleted);
proxy.DownloadStringAsync(new Uri(DataHolder.mainConfigFetchUrl, UriKind.Absolute));
}
void proxy_DownloadStringCompleted(object sender, DownloadStringCompletedEventArgs e)
{
if (e.Error == null)
{
//Process the result...
string data = e.Result;
}
}
For PostClient we will need a WindowsPhonePostClient.dll which can be obtained from http://postclient.codeplex.com/
What is the best way to compose a rest PUT request in C#?
The request has to also send an object not present in the URI.
using(var client = new System.Net.WebClient()) {
client.UploadData(address,"PUT",data);
}
My Final Approach:
public void PutObject(string postUrl, object payload)
{
var request = (HttpWebRequest)WebRequest.Create(postUrl);
request.Method = "PUT";
request.ContentType = "application/xml";
if (payload !=null)
{
request.ContentLength = Size(payload);
Stream dataStream = request.GetRequestStream();
Serialize(dataStream,payload);
dataStream.Close();
}
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
string returnString = response.StatusCode.ToString();
}
public void Serialize(Stream output, object input)
{
var ser = new DataContractSerializer(input.GetType());
ser.WriteObject(output, input);
}
protected void UpdateButton_Click(object sender, EventArgs e)
{
var values = string.Format("Name={0}&Family={1}&Id={2}", NameToUpdateTextBox.Text, FamilyToUpdateTextBox.Text, IdToUpdateTextBox.Text);
var bytes = Encoding.ASCII.GetBytes(values);
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(string.Format("http://localhost:51436/api/employees"));
request.Method = "PUT";
request.ContentType = "application/x-www-form-urlencoded";
using (var requestStream = request.GetRequestStream())
{
requestStream.Write(bytes, 0, bytes.Length);
}
var response = (HttpWebResponse) request.GetResponse();
if (response.StatusCode == HttpStatusCode.OK)
UpdateResponseLabel.Text = "Update completed";
else
UpdateResponseLabel.Text = "Error in update";
}
How to use PUT method using WebRequest.
//JsonResultModel class
public class JsonResultModel
{
public string ErrorMessage { get; set; }
public bool IsSuccess { get; set; }
public string Results { get; set; }
}
// HTTP_PUT Function
public static JsonResultModel HTTP_PUT(string Url, string Data)
{
JsonResultModel model = new JsonResultModel();
string Out = String.Empty;
string Error = String.Empty;
System.Net.WebRequest req = System.Net.WebRequest.Create(Url);
try
{
req.Method = "PUT";
req.Timeout = 100000;
req.ContentType = "application/json";
byte[] sentData = Encoding.UTF8.GetBytes(Data);
req.ContentLength = sentData.Length;
using (System.IO.Stream sendStream = req.GetRequestStream())
{
sendStream.Write(sentData, 0, sentData.Length);
sendStream.Close();
}
System.Net.WebResponse res = req.GetResponse();
System.IO.Stream ReceiveStream = res.GetResponseStream();
using (System.IO.StreamReader sr = new
System.IO.StreamReader(ReceiveStream, Encoding.UTF8))
{
Char[] read = new Char[256];
int count = sr.Read(read, 0, 256);
while (count > 0)
{
String str = new String(read, 0, count);
Out += str;
count = sr.Read(read, 0, 256);
}
}
}
catch (ArgumentException ex)
{
Error = string.Format("HTTP_ERROR :: The second HttpWebRequest object has raised an Argument Exception as 'Connection' Property is set to 'Close' :: {0}", ex.Message);
}
catch (WebException ex)
{
Error = string.Format("HTTP_ERROR :: WebException raised! :: {0}", ex.Message);
}
catch (Exception ex)
{
Error = string.Format("HTTP_ERROR :: Exception raised! :: {0}", ex.Message);
}
model.Results = Out;
model.ErrorMessage = Error;
if (!string.IsNullOrWhiteSpace(Out))
{
model.IsSuccess = true;
}
return model;
}