Develop Reference

c# How to send HTTP command as this - http://192.168.10.1/api/control?alert=101002

I have this hardware from Patlite,
This hardware has an HTTP command control function, for example, if I copy the url "http://192.168.10.1/api/control?alert=101002" to chrome in my computer, it will activate the hardware as needed.
I want to send the command from my code.
I tried this code with no luck:
System.Net.ServicePointManager.Expect100Continue = false;
WebRequest request = WebRequest.Create("http://10.0.22.222/api/control");
request.Method = "post";
request.ContentType = "application/x-www-form-urlencoded";
string postData = "alert=101002";
byte[] byteArray = Encoding.UTF8.GetBytes(postData);
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();
WebResponse response = request.GetResponse();
There is a picture from the manual:
Thanks

You need to create a webrequest instance for this.
WebRequest request = WebRequest.Create("http://192.168.10.1/api/control?alert=101002");
WebResponse response = request.GetResponse();
You may need to set some properties as request method and credentials for this to work.
See this:
https://msdn.microsoft.com/en-us/library/456dfw4f(v=vs.100).aspx

public static string Get(string url, Encoding encoding)
{
try
{
var wc = new WebClient { Encoding = encoding };
var readStream = wc.OpenRead(url);
using (var sr = new StreamReader(readStream, encoding))
{
var result = sr.ReadToEnd();
return result;
}
}
catch (Exception e)
{
//throw e;
return e.Message;
}
}
like this code use the url "http://192.168.10.1/api/control?alert=101002" to send get request.Good luck!

WebClient in .NET Compact Framework 2.0

I've a CF 2.0 project where I need to implement something as below:
var myList = new List<MyItem>() { item1, item2 };
using (var webclient = new WebClient())
{
webclient.Headers["Content-type"] = "application/json";
webclient.Encoding = Encoding.UTF8;
var data = JsonConvert.SerializeObject(myList);
var response = webclient.UploadString("http://111.111.111.111:8762/MyService/FetchData", "POST", data);
var myItems = JsonConvert.DeserializeObject(response, typeof(List<MyItem>));
}
I Cannot find System.Net.WebClient in CF 2.0

The example on this page
is a good one for what I was looking for.
public void Test()
{
// Create a request using a URL that can receive a post.
WebRequest request = WebRequest.Create("http://www.contoso.com/PostAccepter.aspx ");
// Set the Method property of the request to POST.
request.Method = "POST";
// Create POST data and convert it to a byte array.
string postData = "This is a test that posts this string to a Web server.";
byte[] byteArray = Encoding.UTF8.GetBytes(postData);
// Set the ContentType property of the WebRequest.
request.ContentType = "application/json";
// 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 ();
// Get the response.
WebResponse response = request.GetResponse ();
// Display the status.
Console.WriteLine (((HttpWebResponse)response).StatusDescription);
// Get the stream containing content returned by the server.
dataStream = response.GetResponseStream ();
// Open the stream using a StreamReader for easy access.
StreamReader reader = new StreamReader(dataStream);
// Read the content.
string responseFromServer = reader.ReadToEnd();
// Display the content.
Console.WriteLine (responseFromServer);
// Clean up the streams.
reader.Close();
dataStream.Close();
response.Close();
}

How to get post data and request header

I am not able to get post data and request header from the below code on button click event.. here i have to pass an url and a string as a post data...
now when i click button i should get response header, request header, post data and content of the url... but i am not able to get the request header and post data from the below code... can any one tell me where i am wrong
private void button1_Click(object sender, EventArgs e)
{
try
{
string url = txtUrl.Text.Trim();
//HttpWebRequest WebRequestObject = (HttpWebRequest)WebRequest.Create(url);
// string result = null;
string postData = "This";
ASCIIEncoding ObjASCIIEncoding = new ASCIIEncoding();
byte[] fileData = ObjASCIIEncoding.GetBytes(postData);
// Create a request using a URL that can receive a post.
WebRequest request = WebRequest.Create(url);
// Set the Method property of the request to POST.
request.Method = "Post";
// Create POST data and convert it to a byte array.
WebHeaderCollection webh = request.Headers;
txtRequest.Text = webh.ToString();
// Set the ContentType property of the WebRequest.
request.ContentType = "application/x-wwww-form-urlencoded";
// Set the ContentLength property of the WebRequest.
request.ContentLength = fileData.Length;
// Get the request stream.
Stream dataStream = request.GetRequestStream();
// StreamReader r = new StreamReader(dataStream);
// string p = r.ReadToEnd();
// Write the data to the request stream.
dataStream.Write(fileData, 0, fileData.Length);
// Close the Stream object.
dataStream.Close();
//Get the response.
request.Credentials = CredentialCache.DefaultCredentials;
// HttpWebResponse Response = (HttpWebResponse)WebRequestObject.GetResponse();
WebResponse Response = request.GetResponse();
// HttpStatusCode code = Response.StatusCode;
//txtStatus.Text = code.ToString();
txtResponse.Text = Response.Headers.ToString();
// Open data stream:
Stream WebStream = Response.GetResponseStream();
// Create reader object:
StreamReader Reader = new StreamReader(WebStream);
// Read the entire stream content:
txtContent.Text = Reader.ReadToEnd();
// Cleanup
Reader.Close();
WebStream.Close();
Response.Close();
// var request = WebRequest.Create("http://www.livescore.com ");
//var response = request.GetResponse();
}
catch(Exception ex)
{
MessageBox.Show(ex.ToString());
}
}

This should get the header keys and values, remember that each key has an array of values:
Request Headers
To add a header call the Add method:
WebRequest request = WebRequest.Create("http://www.google.com");
request.Method = "GET";
request.Headers.Add("MyTestHeader", "My Test Header Value");
foreach (var headerKey in request.Headers.Keys)
{
var headerValues = request.Headers.GetValues(headerKey.ToString());
Trace.TraceInformation("Request Header:{0}, Value:{1}", headerKey, String.Join(";", headerValues));
}
Response Headers
using (WebResponse response = request.GetResponse())
{
foreach (var headerKey in response.Headers.Keys)
{
var headerValues = response.Headers.GetValues(headerKey.ToString());
Trace.TraceInformation("Response Header: {0}, Value: {1}", headerKey, String.Join(";",headerValues));
}
}

Remote Server returns error 401 Unauthorized Webexception (POST)

I'm trying to solve an issue that I Mostly (70%) have (30% is succesfull).
I trying to do a webrequest (POST) with the following code:
private string HttpWebRequest(string busStopCode)
{
//XML input
string xml = "<?xml version='1.0' encoding='UTF-8' standalone='yes'?><Siri version='1.0' xmlns='http://www.siri.org.uk/'><ServiceRequest> <RequestTimestamp>2011-10-24T15:09:12Z</RequestTimestamp><RequestorRef><username></RequestorRef><StopMonitoringRequest version='1.0'> <RequestTimestamp>2011-10-24T15:09:12Z</RequestTimestamp><MessageIdentifier>12345</MessageIdentifier><MonitoringRef>"+busStopCode+"</MonitoringRef></StopMonitoringRequest></ServiceRequest></Siri>";
string responseFromServer = null;
// Create a request using a URL that can receive a post.
WebRequest request = WebRequest.Create("http://<username>:<username>#nextbus.mxdata.co.uk/nextbuses/1.0/1");
// Set the Method property of the request to POST.
request.Method = "POST";
request.Credentials = CredentialCache.DefaultNetworkCredentials;
// Create POST data and convert it to a byte array.
string postData = xml;
byte[] byteArray = Encoding.UTF8.GetBytes(postData);
// 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();
// Get the response.
WebResponse response = null;
while (response == null)
{
try
{
response = request.GetResponse();
}
catch (Exception e)
{
MessageBox.Show(e.ToString());
}
}
// Display the status.
MessageBox.Show(((HttpWebResponse)response).StatusDescription + " Completed");
// Get the stream containing content returned by the server.
dataStream = response.GetResponseStream();
// Open the stream using a StreamReader for easy access.
StreamReader reader = new StreamReader(dataStream);
// Read the content.
responseFromServer = reader.ReadToEnd();
// Clean up the streams.
reader.Close();
dataStream.Close();
response.Close();
return responseFromServer;
}
When I call this function I get mostly a messagebox of my exception with:
"System.Net.WebException: The remote Server returned an error(401) not authorized with System.Net.Http.Webrequest.GetResponse() with WindowsFormApplication1.Form1.HttpWebRequest(string BusstopCode) in <my pathfile>...."
What I'm doing wrong?
I already tried several solutions from previous threads but without success...
Thanks!

How to use WebRequest to POST some data and read response?

Need to have the server make a POST to an API, how do I add POST values to a WebRequest object and how do I send it and get the response (it will be a string) out?
I need to POST TWO values, and sometimes more, I see in these examples where it says string postData = "a string to post"; but how do I let the thing I am POSTing to know that there is multiple form values?

From MSDN
// Create a request using a URL that can receive a post.
WebRequest request = WebRequest.Create ("http://contoso.com/PostAccepter.aspx ");
// Set the Method property of the request to POST.
request.Method = "POST";
// Create POST data and convert it to a byte array.
string postData = "This is a test that posts this string to a Web server.";
byte[] byteArray = Encoding.UTF8.GetBytes (postData);
// 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 ();
// Get the response.
WebResponse response = request.GetResponse ();
// Display the status.
Console.WriteLine (((HttpWebResponse)response).StatusDescription);
// Get the stream containing content returned by the server.
dataStream = response.GetResponseStream ();
// Open the stream using a StreamReader for easy access.
StreamReader reader = new StreamReader (dataStream);
// Read the content.
string responseFromServer = reader.ReadToEnd ();
// Display the content.
Console.WriteLine (responseFromServer);
// Clean up the streams.
reader.Close ();
dataStream.Close ();
response.Close ();
Take into account that the information must be sent in the format key1=value1&key2=value2

Here's what works for me. I'm sure it can be improved, so feel free to make suggestions or edit to make it better.
const string WEBSERVICE_URL = "http://localhost/projectname/ServiceName.svc/ServiceMethod";
//This string is untested, but I think it's ok.
string jsonData = "{ \"key1\" : \"value1\", \"key2\":\"value2\" }";
try
{
var webRequest = System.Net.WebRequest.Create(WEBSERVICE_URL);
if (webRequest != null)
{
webRequest.Method = "POST";
webRequest.Timeout = 20000;
webRequest.ContentType = "application/json";
using (System.IO.Stream s = webRequest.GetRequestStream())
{
using (System.IO.StreamWriter sw = new System.IO.StreamWriter(s))
sw.Write(jsonData);
}
using (System.IO.Stream s = webRequest.GetResponse().GetResponseStream())
{
using (System.IO.StreamReader sr = new System.IO.StreamReader(s))
{
var jsonResponse = sr.ReadToEnd();
System.Diagnostics.Debug.WriteLine(String.Format("Response: {0}", jsonResponse));
}
}
}
}
catch (Exception ex)
{
System.Diagnostics.Debug.WriteLine(ex.ToString());
}

Here's an example of posting to a web service using the HttpWebRequest and HttpWebResponse objects.
StringBuilder sb = new StringBuilder();
string query = "?q=" + latitude + "%2C" + longitude + "&format=xml&key=xxxxxxxxxxxxxxxxxxxxxxxx";
string weatherservice = "http://api.worldweatheronline.com/free/v1/marine.ashx" + query;
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(weatherservice);
request.Referer = "http://www.yourdomain.com";
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
Stream stream = response.GetResponseStream();
StreamReader reader = new StreamReader(stream);
Char[] readBuffer = new Char[256];
int count = reader.Read(readBuffer, 0, 256);
while (count > 0)
{
String output = new String(readBuffer, 0, count);
sb.Append(output);
count = reader.Read(readBuffer, 0, 256);
}
string xml = sb.ToString();

A more powerful and flexible example can be found here: C# File Upload with form fields, cookies and headers

Below is the code that read the data from the text file and sends it to the handler for processing and receive the response data from the handler and read it and store the data in the string builder class
//Get the data from text file that needs to be sent.
FileStream fileStream = new FileStream(#"G:\Papertest.txt", FileMode.OpenOrCreate, FileAccess.ReadWrite);
byte[] buffer = new byte[fileStream.Length];
int count = fileStream.Read(buffer, 0, buffer.Length);
//This is a handler would recieve the data and process it and sends back response.
WebRequest myWebRequest = WebRequest.Create(#"http://localhost/Provider/ProcessorHandler.ashx");
myWebRequest.ContentLength = buffer.Length;
myWebRequest.ContentType = "application/octet-stream";
myWebRequest.Method = "POST";
// get the stream object that holds request stream.
Stream stream = myWebRequest.GetRequestStream();
stream.Write(buffer, 0, buffer.Length);
stream.Close();
//Sends a web request and wait for response.
try
{
WebResponse webResponse = myWebRequest.GetResponse();
//get Stream Data from the response
Stream respData = webResponse.GetResponseStream();
//read the response from stream.
StreamReader streamReader = new StreamReader(respData);
string name;
StringBuilder str = new StringBuilder();
while ((name = streamReader.ReadLine()) != null)
{
str.Append(name); // Add to stringbuider when response contains multple lines data
}
}
catch (Exception ex)
{
throw ex;
}