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HTTP request with C#

I want to convert the Object received in the function and do as needed to convert it to an object ({"some_key": "some_value"}).
Here is my code:
public HttpRequests(string url, string method, Object data)
{
//The following prepares data, according to received parameter
if (data is Array)
{
data = (Array)data;
}
else if (data is Dictionary<Object, Object>)
{
data = ((Dictionary<string, string>)data)["something"] = platform_secret;
data = ((Dictionary<string, string>)data)["something2"] = "1";
}
method = method.ToUpper(); //POST or GET
this.url = just_url + url;
this.data = Newtonsoft.Json.JsonConvert.SerializeObject(data);
this.method = method;
}
public Object performRequest()
{
if (this.data != null && url != null)
{
WebRequest request = HttpWebRequest.Create(url);
byte[] data_bytes = Encoding.ASCII.GetBytes(Convert.ToChar(data)[]);
//^ this does not work. Am I supposed to do this?
// as I said, what I want is to get an object {key: something} that can be read
// by $_POST["key"] in the server
request.Method = method;
request.ContentType = "application/x-www-form-urlencoded"; //TODO: check
//request.ContentLength = ((Dictionary<string, string>) data);
request.ContentLength = data_bytes.Length;
Stream dataStream = request.GetRequestStream(); //TODO: not async at the moment
//{BEGIN DOUBT
dataStream.Write(data_bytes, 0, data_bytes.Length);
dataStream.Close();
//DOUBT: DO THIS ^ or THIS:_ ???
StreamWriter writer = new StreamWriter(dataStream);
writer.Write(this.data);
//End DOUBT}
WebResponse response = request.GetResponse();
Stream dataResponse = response.GetResponseStream();
writer.Close();
response.Close();
dataStream.Close();
return dataResponse.
}
What exactly am I missing here?

As you initially assign this.data = Newtonsoft.Json.JsonConvert.SerializeObject(data);, suppose his.data has type string (you can change if it is otherwise).
Then instead of byte[] data_bytes = Encoding.ASCII.GetBytes(Convert.ToChar(data)[]); you need to write just byte[] data_bytes = Encoding.ASCII.GetBytes(data);
After use this
//{BEGIN DOUBT
dataStream.Write(data_bytes, 0, data_bytes.Length);
dataStream.Close();
It will help to do the call with some data but it does not help to solve your problem. request.ContentType = "application/x-www-form-urlencoded"; does not expect that the data is Newtonsoft.Json.JsonConvert.SerializeObject serialized. It expects a string containing & separated pairs that are urlencoded.
name1=value1&name2=value2&name3=value3
So, you need to use this format instead of JSON.

You need to use the first piece of code. Here is and exmaple.
But the second piece could work too, I guess. You have missed nothing on C# side. A problem could be in the data you are going to transfer, however. If it is not correctly encoded, for example.

You should be doing something closer to the lines of this...
void Main()
{
var formSerializer = new FormEncodedSerializer();
formSerializer.Add("key", "value");
formSerializer.Add("foo", "rnd");
formSerializer.Add("bar", "random");
var uri = #"http://example.com";
var contentType = #"application/x-www-form-urlencoded";
var postData = formSerializer.Serialize();
var http = new Http();
Console.WriteLine (http.Post(uri, postData, contentType));
}
public class Http
{
public string Post(string url, string data, string format)
{
var content = Encoding.UTF8.GetBytes(data);
var contentLength = content.Length;
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
request.ServicePoint.Expect100Continue = false;
request.Method = "POST";
request.AutomaticDecompression = DecompressionMethods.GZip | DecompressionMethods.Deflate;
request.ContentType = format;
request.ContentLength = contentLength;
using (Stream requestStream = request.GetRequestStream())
{
requestStream.Write(content, 0, content.Length);
}
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
using (Stream responseStream = response.GetResponseStream())
using (StreamReader reader = new StreamReader(responseStream))
{
return reader.ReadToEnd();
}
}
}`
public class FormEncodedSerializer
{
private Dictionary<string, string> formKeysPairs;
public FormEncodedSerializer(): this(new Dictionary<string, string>())
{
}
public FormEncodedSerializer(Dictionary<string, string> kvp)
{
this.formKeysPairs = kvp;
}
public void Add(string key, string value)
{
formKeysPairs.Add(key, value);
}
public string Serialize()
{
return string.Join("", this.formKeysPairs.Select(f => string.Format("&{0}={1}", f.Key,f.Value))).Substring(1);
}
public void Clear()
{
this.formKeysPairs.Clear();
}
}

I did not really understand what your service expects, in which format you have to send the data.
Anyway, if you set ContentType like "application/x-www-form-urlencoded", you must encode your data with this format. You can simply do it with this code;
var values = ((Dictionary<string, string>)data).Aggregate(
new NameValueCollection(),
(seed, current) =>
{
seed.Add(current.Key, current.Value);
return seed;
});
So, your data is sent like "something=platform_secret&something2=1"
Now, you can send form data simply:
WebClient client = new WebClient();
var result = client.UploadValues(url, values);

I think your first function with signature public HttpRequests(string url, string method, Object data) dosn't seem have any logical error but in your second function with signature public Object performRequest() you have some issue:
if your HTTP method is GET you don't need to write content stream.
if your method is POST and your data are JSON you need setting up HTTP requester like this:
request.ContentType = "application/json";
and finally, flush your stream before you close it, like this request.Flush();

How I can pass Json from Win Forms to MVC Controller

I have MVC Controller given below:
public ActionResult ReceiveJson(string json)
{
//--
return Content(json, "application/json");
}
I created Windows Forms Application. In the application I want to pass Json to my MVC Controller.
I use:
string json = new JavaScriptSerializer().Serialize(myObject);
using (var client = new CookieAwareWebClient())
{
var values = new NameValueCollection
{
{ "username", login },
{ "password", haslo },
};
client.UploadValues("http://localhost/xxxxx/Login", values);
string link = "http://localhost/xxx/ReceiveJson";
client.Headers.Add("Content-Type", "application/json");
var response = client.UploadString(new Uri (link), "POST", json);
}
This code doesn't work. In ReceiveJson Controller I received null.
http://s22.postimg.org/9vxu2no9t/json.jpg
Can you tell me how I can pass Json from Win Forms to MVC Controller?
Thanks ;-)

Here is working code example:
var httpWebRequest = (HttpWebRequest)WebRequest.Create("http://localhost/CONTROLLER_NAME/ReceiveJson");
httpWebRequest.ContentType = "application/json";
httpWebRequest.Method = "GET";
using (var streamWriter = new StreamWriter(httpWebRequest.GetRequestStream()))
{
string json = new JavaScriptSerializer().Serialize(myObject);
streamWriter.Write(json);
streamWriter.Flush();
streamWriter.Close();
// If you need to read response
var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();
using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
{
var result = streamReader.ReadToEnd();
}
}

have you checked your json value before send it?
Have you tried to uploadstring without adding extra header? In your action you receave string not an object. Here is a good example.

Looks like you violated some MVC conventions.
First you should post your values in request body not in JSON. It will look like this
using(var content = new MultipartFormDataContent())
{
content.Add(new StringContent(firstPropertyName), "firstValue");
content.Add(new StringContent(secondPropertyName), "secondValue");
client.PostAsync("https://mydomain.com/xxx/ReceiveJson", content);
}
Second you should mark your Action with [HttpPost] attribute
Third you should try to receive your viewModel not a string. It will simplify your code on the server
I believe it will help.

It's a good working version:
public ActionResult NamiaryWyZapis()
{
Stream jsonDane = Request.InputStream;
jsonDane.Seek(0, System.IO.SeekOrigin.Begin);
string json = new StreamReader(jsonDane).ReadToEnd();
//--
}

ANSWER: Via POST.
You need to serialize your object(on this case Persons) to json and make a post with a method like this one. (Person model must be accessible from both applications)
public async bool SendRequestAsync(string requestUrl, object data)
{
string json = JsonConvert.SerializeObject(obj, Formatting.Indented,
new JsonSerializerSettings
{
ReferenceLoopHandling = ReferenceLoopHandling.Ignore
});
try
{
HttpWebRequest request = WebRequest.Create(requestUrl) as HttpWebRequest;
if (request != null)
{
request.Accept = "application/json";
request.ContentType = "application/json";
request.Method = "POST";
using (var stream = new StreamWriter(await request.GetRequestStreamAsync()))
{
stream.Write(json);
}
using (HttpWebResponse response = await request.GetResponseAsync() as HttpWebResponse)
{
if (response != null && response.StatusCode != HttpStatusCode.OK)
throw new Exception(String.Format(
"Server error (HTTP {0}: {1}).",
response.StatusCode,
response.StatusDescription));
if (response != null)
{
Stream responseStream = response.GetResponseStream();
//return true or false depending on the ok
return GetResponseModel(responseStream);
}
}
}
}
catch (WebException ex)
{
var response = ex.Response;
Stream respStream = response.GetResponseStream();
//return true or false depending on the ok
return GetResponseModel(respStream);
}
catch (Exception e)
{
return false;
}
return false;
}
The GetResponseModel method returns the model that you want to read from the web if your POST was success. Then in your WinForms you can register that success if you want.
The controller method will look like this one
[HttpPost]
public ActionResult JsonMethod(Person p)
{
if(p != null)
return Json(true);
else return Json(false);
}
The body of your GetResponse could be like this one
public static T GetResponseModel<T>(Stream respStream) where T : class
{
if (respStream != null)
{
var respStreamReader = new StreamReader(respStream);
Task<string> rspObj = respStreamReader.ReadToEndAsync();
rspObj.Wait();
T jsonResponse = JsonConvert.DeserializeObject<T>(rspObj.Result);
return jsonResponse;
}
return default(T);
}

Sending data to php from windows phone

I need to send some data from windows phone 7 to php page through POST method, I have the following code at wp7 side
public void SendPost()
{
var url = "http://localhost/HelpFello/profile.php";
// Create the web request object
HttpWebRequest webRequest = (HttpWebRequest)WebRequest.Create(url);
webRequest.Method = "POST";
webRequest.ContentType = "application/x-www-form-urlencoded";
// Start the request
webRequest.BeginGetRequestStream(new AsyncCallback(GetRequestStreamCallback), webRequest);
MessageBox.Show("data sent");
}
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 = "user_id=3&name=danish&email_id=mdsiddiquiufo&password=12345&phone_Number=0213&about_me=IRuel2&rating=5";
byte[] byteArray = Encoding.UTF8.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);
var Response = streamReader.ReadToEnd();
streamResponse.Close();
streamReader.Close();
response.Close();
}
catch (WebException e)
{
MessageBox.Show(e.ToString());
}
}
and following on my localhost, to send the data to database
<?php
require_once("constants.php");
$user_id = $_POST['user_id'];
$name = $_POST['name'];
$email_id = $_POST['email_id'];
$password = $_POST['password'];
$phone_number = $_POST['phone_number'];
$about_me = $_POST['about_me'];
$rating = $_POST['rating'];
$query="INSERT INTO profile(User_ID,Name,Email_ID,password,Phone_Number,About_Me,Rating) VALUES ({$user_id},'{$name}','{$email_id}','{$password}',{$phone_number}, '{$about_me}' , {$rating})";
mysql_query($query,$connection);
mysql_close($connection);
?>
When I run the code I have no errors it means code is working fine, but no data is inserted in the database.

I think there is a better way than HttpWebRequest. That is WebClient. You can change the method there and append data like you do in get string. key=value&key2=value then when you invoke that request and get the response try debugging and getting the output from VS or if that is difficult simply assign he string to a textblock in the code. You will get to know if that page has been ever executed or not.
A sample code :
WebClient wc = new WebClient();
wc.UploadStringCompleted += new UploadStringCompletedEventHandler(wc_UploadStringCompleted);
wc.Headers["Content-Type"] = "application/x-www-form-urlencoded";
wc.Encoding = Encoding.UTF8;
Parameters prms = new Parameters();
prms.AddPair("email", email);
prms.AddPair("password", password);
wc.UploadStringAsync(new Uri(loginUrl), "POST", prms.FormPostData(), null);
private void wc_UploadStringCompleted(object sender, UploadStringCompletedEventArgs e)
{
// e.Result will contain the page's output
}
// This is my Parameters and Parameter Object classes
public class Parameters
{
public List<ParameterObject> prms;
public Parameters()
{
prms = new List<ParameterObject>();
}
public void AddPair(string id, string val)
{
prms.Add(new ParameterObject(id, val));
}
public String FormPostData()
{
StringBuilder buffer = new StringBuilder();
for (int i = 0; i < prms.Count; i++)
{
if (i == 0)
{
buffer.Append(System.Net.HttpUtility.UrlEncode(prms[i].id) + "=" + System.Net.HttpUtility.UrlEncode(prms[i].value));
}
else
{
buffer.Append("&" + System.Net.HttpUtility.UrlEncode(prms[i].id) + "=" + System.Net.HttpUtility.UrlEncode(prms[i].value));
}
}
return buffer.ToString();
}
}
public class ParameterObject
{
public string id;
public string value;
public ParameterObject(string id, string val)
{
this.id = id;
this.value = val;
}
}

First error: assuming that no error messages means success
Second error: gaping SQL injection holes
first fix: always assume queries will fail, and check for that condition:
$result = mysql_query($query) or die(mysql_error());
second fix: ditch the mysql_() functions and switch to PDO using prepared statements with placeholders. Boom. No more injection problems, and your code won't stop working on you when mysql_() is removed in a future PHP version.
ps..
3rd error: no quotes on your phone number value. So someone submits 867-5309, and you end up inserting -4442 because mysql saw it as two numbers being subtracted, not a string.

Object reference not set to an instance of an object request.GetResponse()

public static string Method_Name(
string requestMethod,
string requestUrl,
string requestBody = null,
Dictionary<string, string> requestHeader = null,
string requestUserAgent = null,
Boolean isContentType = false)
{
string responseString = String.Empty;
try
{
Uri requestUri = new Uri(requestUrl);
WebRequest request = WebRequest.Create(requestUri);
request.Timeout = 60000;
if (requestHeader != null)
{
foreach (string key in requestHeader.Keys)
{
request.Headers.Add(key, requestHeader[key]);
}
}
request.Headers.Add("X-FD-TrustLevel", "trusted");
request.Headers.Add("X-FD-Version", "1.0");
request.Method = requestMethod;
// For MAS 1.0 POST Call
if (isContentType)
{
request.ContentType = #"application/json";
}
if (!String.IsNullOrEmpty(requestUserAgent))
{
((HttpWebRequest)request).UserAgent = requestUserAgent;
}
if (!String.IsNullOrEmpty(requestBody))
{
Stream stream = request.GetRequestStream();
string requestString = requestBody;
stream.Write(Encoding.Default.GetBytes(requestString), 0, requestString.Length);
stream.Close();
}
/* ERROR */ HttpWebResponse response = (HttpWebResponse)request.GetResponse();
using (StreamReader responseStream = new StreamReader(response.GetResponseStream()))
{
responseString = responseStream.ReadToEnd();
}
}
catch (Exception ex)
{
AnswersExceptionCollection.GetInstance().AddException(ex);
}
return responseString;
}
}
I am getting the following message when code execution reaches HttpWebResponse response = (HttpWebResponse)request.GetResponse();:
Error occurred - Object reference not set to an instance of an object.
I am aware why this kind of error happens, but I am not able to find the root cause in this particular case. Any help will be much appreciated.

Problem must be in these two lines
Uri requestUri = new Uri(requestUrl);
WebRequest request = WebRequest.Create(requestUri);
Verify with breakpoint after executing these lines that whether request is null or not.
If it is null then your provided URL may not exists or may have some other problem.
Regards,
Pavan.G

It seems your initiation on the request
WebRequest request = WebRequest.Create(requestUri);
needs some details of the kind of request. If you're trying to get HttpWebResponse, you have to catch response from HttpWebRequest. here is a quote from MSDN Article.
NoteNote
The WebRequest class is an abstract class.The actual behavior of
WebRequest instances at run time is determined by the descendant class
returned by the WebRequest.Create method.For more information about
default values and exceptions, see the documentation for the
descendant classes, such as HttpWebRequest and FileWebRequest.
So that meant you'll get this clear if you create the request like that
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(requestUri)

Unable to cast object of type 'System.Net.HttpWebRequest' to type 'System.Net.FileWebRequest'

I try download file from server with FileWebRequest. But I get error:
Method on download is here:
public string HttpFileGetReq(Uri uri, int reqTimeout, Encoding encoding)
{
try
{
string stringResponse;
var req = (FileWebRequest)WebRequest.Create(uri);
req.Timeout = reqTimeout;
req.Method = WebRequestMethods.File.DownloadFile;
var res = (FileWebResponse)req.GetResponse();
//using (var receiveStream = res.GetResponseStream())
//using (var readStream = new StreamReader(receiveStream,encoding))
//{
// stringResponse = readStream.ReadToEnd();
//}
return stringResponse="0K";
}
catch (WebException webException)
{
throw webException;
}
}
Usage is here:
public dynamic LoadRoomMsg(IAccount account, string roomId)
{
try
{
string uri = string.Format("http://www-pokec.azet.sk/_s/chat/nacitajPrispevky.php?{0}&lok={1}&lastMsg=0&pub=0&prv=0&r=1295633087203&changeroom=1" , account.SessionId, roomId);
var htmlStringResult = HttpFileGetReq(new Uri(uri), ReqTimeout, EncodingType);
//var htmlStringResult = _httpReq.HttpGetReq(new Uri(string.Format("{0}{1}?{2}&lok=", PokecUrl.RoomMsg,account.SessionId,roomId)),
// ReqTimeout, account.Cookies, EncodingType);
if (!string.IsNullOrEmpty(htmlStringResult))
{
return true;
}
return false;
}
catch (Exception exception)
{
throw exception;
}
}
URL on file is here.
I would like read this file to string variable, that’s all. If anyone have some time and can help me I would be very glad to him.

Your URL (http://...) will produce a HttpWebRequest. You can check with the debugger.
Form MSDN:
The FileWebRequest class implements
the WebRequest abstract base class for
Uniform Resource Identifiers (URIs)
that use the file:// scheme to request
local files.
Note the file:// and local files in there.
Tip: Just use the WebClient class.

Rather than implement your own web streams allow the .NET framework to do it all for you with WebClient, for example:
string uri = string.Format(
"http://www-pokec.azet.sk/_s/chat/nacitajPrispevky.php?{0}&lok={1}&lastMsg=0&pub=0&prv=0&r=1295633087203&changeroom=1",
account.SessionId,
roomId);
System.Net.WebClient wc = new System.Net.WebClient();
string webData = wc.DownloadString(uri);
...parse the webdata response here...
Looking at the response from the URL you posted:
{"reason":0}
parsing that should be a simple task with a little string manipulation.

Change FileWebRequest and FileWebResponse to HttpWebRequest and HttpWebResponse.
It doesn't matter that what you're downloading may be a file; as far as the .NET Framework is concerned, you're just retrieving a page from a website.

FileWebRequest is for file:// protocols. Since you're using an http:// url, you want to use HttpWebRequest.
public string HttpFileGetReq(Uri uri, int reqTimeout, Encoding encoding)
{
string stringResponse;
var req = (HttpWebRequest)WebRequest.Create(uri);
req.Timeout = reqTimeout;
var res = (HttpWebResponse)req.GetResponse();
using (var receiveStream = res.GetResponseStream())
{
using (var readStream = new StreamReader(receiveStream,encoding))
{
return readStream.ReadToEnd();
}
}
}