Develop Reference

C# HttpWebRequest.GetResponse encoding URL

I am using the C# HttpWebRequest.GetResponse with a URL that is not encoded. But when I inspect the request using fiddler I see that the URL is encoded. I wanted to confirm that HttpWebRequest Class is encoding the URL internally but could not find it in the documentation. Can someone point me to the documentation where i can find this or some other way to validate it?
KR

Here it is:
WebRequest.Create (you are using that method to create your HttpWebRequest object, right?) says "The Create method uses the requestUriString parameter to create a Uri instance that it passes to the new WebRequest"
https://msdn.microsoft.com/en-us/library/bw00b1dc(v=vs.110).aspx
The constructor for Uri (which is being called by the Create method) says it "parses the URI, puts it in canonical format, and makes any required escape encodings"
https://msdn.microsoft.com/en-us/library/z6c2z492(v=vs.110).aspx

//endpoint is url and method can be post or get... the below will help you to catch any errors from server..
make it a function so its wll be easy for you to use where ever you want ...
HttpWebRequest httpRequest = (HttpWebRequest)HttprequestObject(endpoints, method);
using (var streamWriter = new StreamWriter(httpRequest.GetRequestStream()))
{
streamWriter.Write(jsonObject);
streamWriter.Flush();
streamWriter.Close();
}
var result = "";
HttpWebResponse httpResponse;
try
{
httpResponse = (HttpWebResponse)httpRequest.GetResponse();
using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
{
result = streamReader.ReadToEnd();
}
}
catch (WebException e)
{
Console.WriteLine("This program is expected to throw WebException on successful run." +
"\n\nException Message :" + e.Message);
if (e.Status == WebExceptionStatus.ProtocolError)
{
Console.WriteLine("Status Code : {0}", ((HttpWebResponse)e.Response).StatusCode);
Console.WriteLine("Status Description : {0}", ((HttpWebResponse)e.Response).StatusDescription);
using (Stream data = e.Response.GetResponseStream())
using (var reader = new StreamReader(data))
{
string text = reader.ReadToEnd();
Console.WriteLine(text);
}
}
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}

or u want class and u want to use for creating api lib then just copy paste this class ..this is for c# but almost similer syntax for java ...
with this u can access any api or url or also used to pass json file to server ..
using Newtonsoft.Json.Linq;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Text;
using System.Threading.Tasks;
namespace ExternalAPIs_SynapsePay.Helpers
{
class RESTHelpers
{
public dynamic APICalls(JObject jsonObject, string endpoints, string method)
{
HttpWebRequest httpRequest = (HttpWebRequest)HttprequestObject(endpoints, method);
using (var streamWriter = new StreamWriter(httpRequest.GetRequestStream()))
{
streamWriter.Write(jsonObject);
streamWriter.Flush();
streamWriter.Close();
}
var result = "";
HttpWebResponse httpResponse;
try
{
httpResponse = (HttpWebResponse)httpRequest.GetResponse();
using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
{
result = streamReader.ReadToEnd();
}
}
catch (WebException e)
{
Console.WriteLine("This program is expected to throw WebException on successful run." +
"\n\nException Message :" + e.Message);
if (e.Status == WebExceptionStatus.ProtocolError)
{
Console.WriteLine("Status Code : {0}", ((HttpWebResponse)e.Response).StatusCode);
Console.WriteLine("Status Description : {0}", ((HttpWebResponse)e.Response).StatusDescription);
using (Stream data = e.Response.GetResponseStream())
using (var reader = new StreamReader(data))
{
string text = reader.ReadToEnd();
Console.WriteLine(text);
}
}
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
return result;
//return "Success";
//not sure what to return
//here i have to add sql server code to enter into database
}
public HttpWebRequest HttprequestObject(string endpoints, string method)
{
string url = Setting.API_TEST_VALUE + endpoints;
var httpWebRequest = (HttpWebRequest)WebRequest.Create(url);
httpWebRequest.ContentType = "application/json";
httpWebRequest.Method = method;
return httpWebRequest;
}
/// <summary>
/// This method is useful when you have to pass JSON as string not as object... This is basically a constructor..
/// Even if u pass json object it will accept, so no need to worry about that.
/// </summary>
/// <param name="ljson"></param>
/// <param name="endpoints"></param>
/// <param name="method"></param>
/// <returns></returns>
public dynamic APICalls(string jsonString, string endpoints, string method)
{
HttpWebRequest httpRequest = (HttpWebRequest)HttprequestObject(endpoints, method);
using (var streamWriter = new StreamWriter(httpRequest.GetRequestStream()))
{
streamWriter.Write(jsonString);
streamWriter.Flush();
streamWriter.Close();
}
var result = "";
HttpWebResponse httpResponse;
try
{
httpResponse = (HttpWebResponse)httpRequest.GetResponse();
using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
{
result = streamReader.ReadToEnd();
}
}
catch (WebException e)
{
Console.WriteLine("This program is expected to throw WebException on successful run." +
"\n\nException Message :" + e.Message);
if (e.Status == WebExceptionStatus.ProtocolError)
{
Console.WriteLine("Status Code : {0}", ((HttpWebResponse)e.Response).StatusCode);
Console.WriteLine("Status Description : {0}", ((HttpWebResponse)e.Response).StatusDescription);
using (Stream data = e.Response.GetResponseStream())
using (var reader = new StreamReader(data))
{
string text = reader.ReadToEnd();
Console.WriteLine(text);
result = text;
}
}
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
return result;
//return "Success";
//not sure what to return
//here i have to add sql server code to enter into database
}
public void HttlpResponseObject(HttpWebRequest httpResponse)
{
var response = (HttpWebResponse)httpResponse.GetResponse();
using (var streamReader = new StreamReader(response.GetResponseStream()))
{
var result = streamReader.ReadToEnd();
}
//entry into databse can be done from here
//or it should return some value
}
}
}

Post json to xamarin webclient api

I want to post a jsonobject to my webapi. Using normal C# code i would use PostAsJsonAsync on my httpClient object. But that doesn't seem to be supported with xamarin. So my question is how do i post json to my api using xamarin webclient or webrequest?
Here is my code right now that returns null...
protected async override void OnResume()
{
base.OnResume();
var clientRequest = new ResourceByNameRequest
{
Name = "G60",
UserId = "1"
};
HttpContent myContent = new StringContent(clientRequest.ToString());
try
{
using (var client = new HttpClient())
{
client.BaseAddress = new Uri("XXX");
var cancellationToken = new CancellationToken();
var response = client.PostAsync("/api/Resource/ResourceByName", myContent, cancellationToken).Result;
var result = await response.Content.ReadAsStreamAsync();
//return result;
}
}
catch (Exception)
{
throw;
}
}

Try something like this:
using System.Runtime.Serialization;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
//...
protected override void OnResume()
{
var request = HttpWebRequest.Create("Your_URL_XXX");
request.ContentType = "application/json";
request.Method = "POST";
var clientRequest = new ResourceByNameRequest
{
Name = "G60",
UserId = "1"
};
using (var writer = new StreamWriter(request.GetRequestStream()))
{
writer.Write(clientRequest.ToString());
}
try
{
using (HttpWebResponse response = request.GetResponse() as HttpWebResponse)
{
string error = "";
if (response.StatusCode != HttpStatusCode.OK)
error = string.Format("Error fetching data. Server returned status code: {0} | Description: {1}", response.StatusCode, response.StatusDescription);
using (StreamReader reader = new StreamReader(response.GetResponseStream()))
{
var content = reader.ReadToEnd();
if (string.IsNullOrWhiteSpace(content))
{
strResponse = "Response contained empty body...";
}
else
{
var cont = JObject.Parse(content);
YOUR_OBJECT_RESPONSE.PROP1 = cont["Prop1"].NullSafeToString();
YOUR_OBJECT_RESPONSE.PROP2 = cont["Prop2"].NullSafeToString();
//...
}
}
}
}
catch (WebException wex)
{
var pageContent = new StreamReader(wex.Response.GetResponseStream()).ReadToEnd();
}
}

Returning value from a method

I have the following code:
public class Request
{
static string username = "ha#gmail.com";
public string Send()
{
///some variables
try
{
///
}
catch (WebException e)
{
using (WebResponse response = e.Response)
{
HttpWebResponse httpResponse = (HttpWebResponse)response;
Console.WriteLine("Error code: {0}", httpResponse.StatusCode);
using (Stream Data = response.GetResponseStream())
{
string text = new StreamReader(Data).ReadToEnd();
}
}
}
return text;
}
}
Getting an error: 'text' does' t exist in the current context. How to return the 'Text' value from the method.

public string Send()
{
//define the variable outside of try catch
string text = null; //Define at method scope
///some variables
try
{
///
}
catch (WebException e)
{
using (WebResponse response = e.Response)
{
HttpWebResponse httpResponse = (HttpWebResponse)response;
Console.WriteLine("Error code: {0}", httpResponse.StatusCode);
using (Stream Data = response.GetResponseStream())
{
text = new StreamReader(Data).ReadToEnd();
}
}
}
return text;
}

public string Send()
{
try {
return "Your string value";
}
catch (WebException e) {
using (WebResponse response = e.Response) {
HttpWebResponse httpResponse = (HttpWebResponse)response;
Console.WriteLine("Error code: {0}", httpResponse.StatusCode);
using (Stream Data = response.GetResponseStream())
{
return new StreamReader(Data).ReadToEnd();
}
}
}
}

You have to initialize variable before try clause to use it outside of try:
public string Send()
{
string text = null;
try
{
}
catch (WebException e)
{
using (WebResponse response = e.Response)
{
HttpWebResponse httpResponse = (HttpWebResponse)response;
Console.WriteLine("Error code: {0}", httpResponse.StatusCode);
using (Stream Data = response.GetResponseStream())
{
text = new StreamReader(Data).ReadToEnd();
}
}
}
return text;
}

You need to define text as a local variable in Send(), not inside a sublocal block like here inside using(...). Such it would be only valid there.

Sending xml using Apache HttpComponents

I am attempting to replicate the following C# code in Java. This code is a helper class that sends a request containing xml, and reads a response.
internal static String Send(String url, String body)
{
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(url);
try
{
// create the new httpwebrequest with the uri
request.ContentLength = 0;
// set the method to POST
request.Method = "POST";
if (!String.IsNullOrEmpty(body))
{
request.ContentType = "application/xml; charset=utf-8";
byte[] postData = Encoding.Default.GetBytes(body);
request.ContentLength = postData.Length;
using (Stream s = request.GetRequestStream())
{
s.Write(postData, 0, postData.Length);
}
}
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
String responseString = new StreamReader(response.GetResponseStream()).ReadToEnd();
if (response.StatusCode != HttpStatusCode.OK)
{
throw new ResponseException(((int)response.StatusCode),
response.StatusCode.ToString(), request.RequestUri.ToString(),
responseString);
}
return responseString;
}
}
catch (WebException e)
{
using (WebResponse response = e.Response)
{
HttpWebResponse httpResponse = response as HttpWebResponse;
if (httpResponse != null)
{
using (Stream data = response.GetResponseStream())
{
data.Position = 0;
throw new ResponseException(((int)httpResponse.StatusCode),
httpResponse.StatusCode.ToString(), request.RequestUri.ToString(),
new StreamReader(data).ReadToEnd()
);
}
}
else
{
throw;
}
After reading other threads I determined that the Apache HttpComponents library would be my best bet to get the same functionality. After reading the documentation and following the example here:
http://hc.apache.org/httpcomponents-client-ga/quickstart.html
I am unable to figure out how to send the body string as xml. When I attempt to set the entity for the request it requires that I declare a BasicNameValuePair, and I do not understand what this is, or how I would format the body string to meet this specification.
Below is what I have currently done.
protected static String Send(String url, String body)
{
HttpPost request = new HttpPost(url);
try
{
request.setHeader("ContentType", "application/xml; charset=utf=8");
// Encode the body if needed
request.setEntity(new UrlEncodedFormEntity());
//get the response
// if the response code is not valid throw a ResponseException
// else return the response string.
} finally {
request.releaseConnection();
}
return null;
}
EDIT : or should I use a StringEntity and do the following
protected static String SendToJetstream(String url, String body)
{
HttpPost request = new HttpPost(url);
try
{
StringEntity myEntity = new StringEntity(body,
ContentType.create("application/xml", "UTF-8"));
// Encode the body if needed
request.setEntity(myEntity);
//get the response
// if the response code is not valid throw a ResponseException
// else return the response string.
} finally {
request.releaseConnection();
}
return null;
}

Use a FileEntity
File file = new File("somefile.xml");
FileEntity entity = new FileEntity(file, ContentType.create("application/xml", "UTF-8"));
Lots of good examples here: http://hc.apache.org/httpcomponents-client-ga/tutorial/html/fundamentals.html#d5e165

Create HTTP post request and receive response using C# console application

I need to post data to a URL (https://somesite.com) to download file in responseStrem based on the parameters I posted.
How can I do that using a C# console application?
Parameters:
filename,
userid,
password,
type

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.IO;
namespace WebserverInteractionClassLibrary
{
public class RequestManager
{
public string LastResponse { protected set; get; }
CookieContainer cookies = new CookieContainer();
internal string GetCookieValue(Uri SiteUri,string name)
{
Cookie cookie = cookies.GetCookies(SiteUri)[name];
return (cookie == null) ? null : cookie.Value;
}
public string GetResponseContent(HttpWebResponse response)
{
if (response == null)
{
throw new ArgumentNullException("response");
}
Stream dataStream = null;
StreamReader reader = null;
string responseFromServer = null;
try
{
// Get the stream containing content returned by the server.
dataStream = response.GetResponseStream();
// Open the stream using a StreamReader for easy access.
reader = new StreamReader(dataStream);
// Read the content.
responseFromServer = reader.ReadToEnd();
// Cleanup the streams and the response.
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
finally
{
if (reader != null)
{
reader.Close();
}
if (dataStream != null)
{
dataStream.Close();
}
response.Close();
}
LastResponse = responseFromServer;
return responseFromServer;
}
public HttpWebResponse SendPOSTRequest(string uri, string content, string login, string password, bool allowAutoRedirect)
{
HttpWebRequest request = GeneratePOSTRequest(uri, content, login, password, allowAutoRedirect);
return GetResponse(request);
}
public HttpWebResponse SendGETRequest(string uri, string login, string password, bool allowAutoRedirect)
{
HttpWebRequest request = GenerateGETRequest(uri, login, password, allowAutoRedirect);
return GetResponse(request);
}
public HttpWebResponse SendRequest(string uri, string content, string method, string login, string password, bool allowAutoRedirect)
{
HttpWebRequest request = GenerateRequest(uri, content, method, login, password, allowAutoRedirect);
return GetResponse(request);
}
public HttpWebRequest GenerateGETRequest(string uri, string login, string password, bool allowAutoRedirect)
{
return GenerateRequest(uri, null, "GET", null, null, allowAutoRedirect);
}
public HttpWebRequest GeneratePOSTRequest(string uri, string content, string login, string password, bool allowAutoRedirect)
{
return GenerateRequest(uri, content, "POST", null, null, allowAutoRedirect);
}
internal HttpWebRequest GenerateRequest(string uri, string content, string method, string login, string password, bool allowAutoRedirect)
{
if (uri == null)
{
throw new ArgumentNullException("uri");
}
// Create a request using a URL that can receive a post.
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(uri);
// Set the Method property of the request to POST.
request.Method = method;
// Set cookie container to maintain cookies
request.CookieContainer = cookies;
request.AllowAutoRedirect = allowAutoRedirect;
// If login is empty use defaul credentials
if (string.IsNullOrEmpty(login))
{
request.Credentials = CredentialCache.DefaultNetworkCredentials;
}
else
{
request.Credentials = new NetworkCredential(login, password);
}
if (method == "POST")
{
// Convert POST data to a byte array.
byte[] byteArray = Encoding.UTF8.GetBytes(content);
// Set the ContentType property of the WebRequest.
request.ContentType = "application/x-www-form-urlencoded";
// Set the ContentLength property of the WebRequest.
request.ContentLength = byteArray.Length;
// Get the request stream.
Stream dataStream = request.GetRequestStream();
// Write the data to the request stream.
dataStream.Write(byteArray, 0, byteArray.Length);
// Close the Stream object.
dataStream.Close();
}
return request;
}
internal HttpWebResponse GetResponse(HttpWebRequest request)
{
if (request == null)
{
throw new ArgumentNullException("request");
}
HttpWebResponse response = null;
try
{
response = (HttpWebResponse)request.GetResponse();
cookies.Add(response.Cookies);
// Print the properties of each cookie.
Console.WriteLine("\nCookies: ");
foreach (Cookie cook in cookies.GetCookies(request.RequestUri))
{
Console.WriteLine("Domain: {0}, String: {1}", cook.Domain, cook.ToString());
}
}
catch (WebException ex)
{
Console.WriteLine("Web exception occurred. Status code: {0}", ex.Status);
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
return response;
}
}
}

Take a look at the System.Net.WebClient class, it can be used to issue requests and handle their responses, as well as to download files:
http://www.hanselman.com/blog/HTTPPOSTsAndHTTPGETsWithWebClientAndCAndFakingAPostBack.aspx
http://msdn.microsoft.com/en-us/library/system.net.webclient(VS.90).aspx

For this you can simply use the "HttpWebRequest" and "HttpWebResponse" classes in .net.
Below is a sample console app I wrote to demonstrate how easy this is.
using System;
using System.Collections.Generic;
using System.Text;
using System.Net;
using System.IO;
namespace Test
{
class Program
{
static void Main(string[] args)
{
string url = "www.somewhere.com";
string fileName = #"C:\output.file";
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
request.Timeout = 5000;
try
{
using (WebResponse response = (HttpWebResponse)request.GetResponse())
{
using (FileStream stream = new FileStream(fileName, FileMode.Create, FileAccess.Write))
{
byte[] bytes = ReadFully(response.GetResponseStream());
stream.Write(bytes, 0, bytes.Length);
}
}
}
catch (WebException)
{
Console.WriteLine("Error Occured");
}
}
public static byte[] ReadFully(Stream input)
{
byte[] buffer = new byte[16 * 1024];
using (MemoryStream ms = new MemoryStream())
{
int read;
while ((read = input.Read(buffer, 0, buffer.Length)) > 0)
{
ms.Write(buffer, 0, read);
}
return ms.ToArray();
}
}
}
}
Enjoy!

HttpWebRequest request =(HttpWebRequest)WebRequest.Create("some url");
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
request.UserAgent = "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 7.1; Trident/5.0)";
request.Accept = "/";
request.UseDefaultCredentials = true;
request.Proxy.Credentials = System.Net.CredentialCache.DefaultCredentials;
doc.Save(request.GetRequestStream());
HttpWebResponse resp = request.GetResponse() as HttpWebResponse;
Hope it helps

Insted of using System.Net.WebClient I would recommend to have a look on System.Net.Http.HttpClient which was introduced with net 4.5 and makes your life much easier.
Also microsoft recommends to use the HttpClient on this article
http://msdn.microsoft.com/en-us/library/system.net.webclient(VS.90).aspx
An example could look like this:
var client = new HttpClient();
var content = new MultipartFormDataContent
{
{ new StringContent("myUserId"), "userid"},
{ new StringContent("myFileName"), "filename"},
{ new StringContent("myPassword"), "password"},
{ new StringContent("myType"), "type"}
};
var responseMessage = await client.PostAsync("some url", content);
var stream = await responseMessage.Content.ReadAsStreamAsync();