Develop Reference

Rest URL consumption guidance required

I have a rest url provided by client , It looks something like www.baseurl/api// I couldn't get result if I try to consume it from console application getting error 503.
However I m able to browse it from my browser and it returns the proper json of Entity Details. Please help me with this.
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;
using System.Threading.Tasks;
namespace ConsoleApp15
{
public class Class1
{
private const string URL = "www.baseurl/api/<EntityName>/<EntityID>";
static void Main(string[] args)
{
Class1.CreateObject();
}
private static void CreateObject()
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(URL);
request.Method = "GET";
request.ContentType = "application/json";
try
{
WebResponse webResponse = request.GetResponse();
using (Stream webStream = webResponse.GetResponseStream() ?? Stream.Null)
using (StreamReader responseReader = new StreamReader(webStream))
{
string response = responseReader.ReadToEnd();
Console.Out.WriteLine(response);
}
}
catch (Exception e)
{
Console.Out.WriteLine("-----------------");
Console.Out.WriteLine(e.Message);
}
}
}
}

How to make cURL call in C#

How can I make the following cURL call via C# console app.
curl -k https://serverName/clearprofile.ashx -H "Host: example.com"
I have tried CurlSharp. Unfortunately I could not build successfully this project because of missing libcurlshim64 assembly.
From here I understood that the best approach is by using HttpClient class, but I don`t know how exactly to make the above mentioned cURL call from my console application.

If you just want something simple I would use the HttpClient class built into the .Net Framework like this:
using System.Net.Http;
using System.Threading.Tasks;
namespace ScrapCSConsole
{
class Program
{
static void Main(string[] args)
{
HttpClient client = new HttpClient();
client.DefaultRequestHeaders.Host = "example.com";
Task<string> task = client.GetStringAsync("https://serverName/clearprofile.ashx");
task.Wait();
Console.WriteLine(task.Result);
}
}
}
For more complex stuff, you can also use the HttpWebRequest class like this:
using System;
using System.IO;
using System.Net;
namespace ScrapCSConsole
{
class Program
{
static void Main(string[] args)
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://google.co.uk");
request.Host = "example.com";
HttpStatusCode code;
string responseBody = String.Empty;
try
{
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
code = response.StatusCode;
using (StreamReader reader = new StreamReader(response.GetResponseStream()))
{
responseBody = reader.ReadToEnd();
}
}
}
catch (WebException webEx)
{
using (HttpWebResponse response = (HttpWebResponse)webEx.Response)
{
code = response.StatusCode;
using (StreamReader reader = new StreamReader(response.GetResponseStream()))
{
responseBody = reader.ReadToEnd();
}
}
}
Console.WriteLine($"Status: {code}");
Console.WriteLine(responseBody);
}
}
}

adding an Interface

My main Program.cs is as follows:
using System;
using System.Collections.Generic;
using System.Net.NetworkInformation;
using System.Net.Sockets;
using System.IO;
using System.Threading.Tasks;
namespace HTTPrequestApp
{
class Program
{
static void Main(string[] args)
{
var lstWebSites = new List<string>
{
"www.amazon.com",
"www.ebay.com",
"www.att.com",
"www.verizon.com",
"www.sprint.com",
"www.centurylink.com",
"www.yahoo.com"
};
string filename = #"RequestLog.txt";
{
using (var writer = new StreamWriter(filename, true))
{
foreach (string website in lstWebSites)
{
for (var i = 0; i < 4; i++)
{
MyWebRequest request = new MyWebRequest();
request.Request();
}
}
}
}
}
}
}
Then I have a class, and this is where the errors are.
The GetList() error - 'HTTPrequestApp.Program' does not contain a definition for 'GetList'
The client2 error - The name 'client2' does not exist in the current content
MyWebRequest.cs
using System;
using System.Collections.Generic;
using System.IO;
using System.Net.NetworkInformation;
using System.Net.Sockets;
using System.Threading.Tasks;
namespace HTTPrequestApp
{
public class MyWebRequest : HTTPrequestApp.IWebRequest
{
public void Request()
{
List<string> lstWebSites = Program.GetList();
using (var client = new TcpClient(lstWebSites[1], 80))
{
using (NetworkStream stream = client2.GetStream())
using (StreamWriter writer = new StreamWriter(stream))
using (StreamReader reader2 = new StreamReader(stream))
{
writer.AutoFlush = true;
writer.WriteLine("GET / HTTP/1.1");
writer.WriteLine("HOST: {0}:80", lstWebSites[1]);
writer.WriteLine("Connection: Close");
writer.WriteLine();
writer.WriteLine();
string theresponse = reader2.ReadToEnd();
Console.WriteLine(theresponse);
}
}
}
}
}
Finally, I have an Interface. Is this done correctly?
If I am doing something incorrectly please help me, how should I fix it?
IWebRequest.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace HTTPrequestApp
{
interface IWebRequest
{
void Request();
}
}
What I have to do is: send HTTP request to get the initial page and get back the HTTP response. Save it into the .cvs file. Check that it is a 200 response code and time how long it took to retrieve the response. I have to get the response 4 times from each of those websites in my list.
Please help me.

First about your errors :
The provided code does not contain GetList method in Program class as the code shared contains the only main method which defines your websites.
The line using (var client = new TcpClient(lstWebSites[1], 80)) creates client object instead of client2.
Another point, instead of writing to open TCPClient connection to read the response of website you can use HttpClient or WebRequest in-built classes to achieve your functionality.

Here's a full example of what I mean. Keep adding all the websites you want to lstWebSites, and instead of dumping the HTML results to the console, you can write them to a file.
var lstWebSites = new List<string>
{
"https://www.stackoverflow.com",
"https://www.google.com"
};
foreach (string website in lstWebSites)
{
var request = WebRequest.Create(website);
request.Credentials = CredentialCache.DefaultCredentials;
((HttpWebRequest)request).UserAgent = "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2228.0 Safari/537.36"; // Lie
var response = request.GetResponse();
if (((HttpWebResponse)response).StatusCode == HttpStatusCode.OK)
{
var stream = response.GetResponseStream();
var reader = new StreamReader(stream);
Console.WriteLine(string.Format("***** {0} *****", website));
Console.WriteLine(reader.ReadToEnd()); // Dump HTML response
}
}

Creating a login session to a webpage

I hope I ask in the correct way in here as it is my first in stackoverflow.
I am pretty new in C# and WP8, but I am working on a small project where I through my WP8 app login to my page and then my wish is to be able to, after the login, to somehow use the session/cookie from the login to navigate in a WebBrowser control through the other "protected" pages.
I have indeed searched the forums and the net, but I have not found the specific answer elsewhere.
Below I have my login session which works and "result" gives me the HTML of the page after login. But then I am a bit stuck...
Maybe there is a better/smarter/easier way?
Best Regards
Martin
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Navigation;
using Microsoft.Phone.Controls;
using Microsoft.Phone.Shell;
using HTTPPost.Resources;
using System.IO;
using System.Text;
using System.Diagnostics;
using System.Text.RegularExpressions;
namespace HTTPPost
{
public partial class MainPage : PhoneApplicationPage
{
public MainPage()
{
InitializeComponent();
Loaded += new RoutedEventHandler(MainPage_Loaded);
}
void MainPage_Loaded(object sender, RoutedEventArgs e)
{
System.Uri myUri = new System.Uri("http://homepage.com/index.php");
HttpWebRequest myRequest = (HttpWebRequest)HttpWebRequest.Create(myUri);
myRequest.Method = "POST";
myRequest.ContentType = "application/x-www-form-urlencoded";
myRequest.BeginGetRequestStream(new AsyncCallback(GetRequestStreamCallback), myRequest);
}
void GetRequestStreamCallback(IAsyncResult callbackResult)
{
HttpWebRequest myRequest = (HttpWebRequest)callbackResult.AsyncState;
// End the stream request operation
Stream postStream = myRequest.EndGetRequestStream(callbackResult);
// Create the post data
string postData = "user=usernamepass=password";
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
myRequest.BeginGetResponse(new AsyncCallback(GetResponsetStreamCallback), myRequest);
}
void GetResponsetStreamCallback(IAsyncResult callbackResult)
{
HttpWebRequest request = (HttpWebRequest)callbackResult.AsyncState;
HttpWebResponse response = (HttpWebResponse)request.EndGetResponse(callbackResult);
using (StreamReader httpWebStreamReader = new StreamReader(response.GetResponseStream()))
{
string result;
result = httpWebStreamReader.ReadToEnd();
MiniBrowser.NavigateToString(result);
Debug.WriteLine(result);
}
}
}
}

Well, there is lots of answers about getting and storing cookies, but I have a trick to avoid using them. The trick is to use same instance of WebClient for all requests on this page after login sequence. See my code:
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;
namespace SomeApp
{
public class WebRequests
{
//Making property of HttpClient
private static HttpClient _client;
public static HttpClient Client
{
get { return _client; }
set { _client = value; }
}
//method to download string from page
public static async Task<string> LoadPageAsync(string p)
{
if (Client == null)// that means we need to login to page
{
Client = await Login(Client);
}
return await Client.GetStringAsync(p);
}
// method for logging in
public static async Task<HttpClient> Login(HttpClient client)
{
client = new HttpClient();
var content = new FormUrlEncodedContent(new[]
{
new KeyValuePair<string, string>("email", "someone#example.com"),
new KeyValuePair<string, string>("password", "SoMePasSwOrD")
});
var response = await client.PostAsync("https://www.website.com/login.php", content);
return client;
}
var page1Html = await LoadPageAsync("https://www.website.com/page1.php");
}
}

Call to OData service from C#

I use the code below to call an OData service (which is the working service from Odata.org) from C# and I don't get any result.The error is in the response.GetResponseStream().
Here is the error :
Length = 'stream.Length' threw an exception of type 'System.NotSupportedException'
I want to call to the service and parse the data from it, what is the simpliest way to do that?
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Web;
using System.Net;
using System.IO;
using System.Xml;
namespace ConsoleApplication1
{
public class Class1
{
static void Main(string[] args)
{
Class1.CreateObject();
}
private const string URL = "http://services.odata.org/OData/OData.svc/Products?$format=atom";
private static void CreateObject()
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(URL);
request.Method = "GET";
request.ContentType = "application/xml";
request.Accept = "application/xml";
using (WebResponse response = request.GetResponse())
{
using (Stream stream = response.GetResponseStream())
{
XmlTextReader reader = new XmlTextReader(stream);
}
}
}
}
}

I ran your code on my machine, and it executed fine, I was able to traverse all XML elements retrieved by the XmlTextReader.
var request = (HttpWebRequest)WebRequest.Create(URL);
request.Method = "GET";
request.ContentType = "application/xml";
request.Accept = "application/xml";
using (var response = request.GetResponse())
{
using (var stream = response.GetResponseStream())
{
var reader = new XmlTextReader(stream);
while (reader.Read())
{
Console.WriteLine(reader.Value);
}
}
}
But as #qujck suggested, take a look at HttpClient. It's much easier to use.

If you're running .NET 4.5 then take a look at HttpClient (MSDN)
HttpClient client = new HttpClient();
client.DefaultRequestHeaders.Accept.Add(
new MediaTypeWithQualityHeaderValue("application/json"));
HttpResponseMessage response = await client.GetAsync(endpoint);
Stream stream = await response
.Content.ReadAsStreamAsync().ConfigureAwait(false);
response.EnsureSuccessStatusCode();
See here and here for complete examples