Develop Reference

C# Creating Equivalent HttpRequestMessage for HttpWebRequest code

I was told to migrate a post request written in HttpWebRequest to HttpRequestMessage.
I've provided the old code and the new code that I've developed below.
In the old code they are sending the byte stream over to the
endpoint. I'm not sure whether using HttpWebRequest demands data to be sent as bytes or not.
In the new code, I've created a StringContent to be sent to the endpoint. Are both the codes equivalent and works the intended way?
If not, some help to modify the new code is appreciated.
Using HttpWebRequest (old code)
//postData -> data to be sent(type string)
HttpWebRequest req = (HttpWebRequest)WebRequest.Create("someurl.net");
req.ContentType = "application/xml";
req.Accept = "application/xml";
byte[] postBytes = Encoding.UTF8.GetBytes(postData);
req.ContentLength = postBytes.Length;
Stream postStream = req.GetRequestStream();
postStream.Write(postBytes, 0, postBytes.Length);
postStream.Flush();
postStream.Close();
WebResponse resp = req.GetResponse();
Using HttpRequestMessage (new code)
//postData -> data to be sent(type string)
var request = new HttpRequestMessage(HttpMethod.Post, $"{address}");
request.Headers.Add("Accept", "application/xml");
request.Headers.Add("Content-Type", "application/xml");
request.Content = new StringContent(RSAEncryptDecrypt.EncryptResponse(postData));
await _client.SendAsync(request, HttpCompletionOption.ResponseHeadersRead, cancellationToken)

I suppose it depends on what the intent was originally :-)
HttpWebRequest is very flexible to what it will send out. Byte[], FormUrlEncodedContent, Multipart Content, Stream, String, ...you get the idea.
There are some performance considerations, again depending on your content. End of the day if you test it and it passes within the required parameters, then you should be OK. Given someone is telling you to do it, it might be in your best interest to ask said someone a few additional questions.
One thing that does stick out to me, in the original code your string is encoded in UTF8 and your new code appears to perhaps be something else. May want to explicitly call out the encoding parameter of StringContent if you choose to keep going that way.
Here's a quick example that should get you up and going. A little inflated, but hopefully it helps you out :-)
public static void PostSomeContent(string data_parameter, string uri_parameter){
HttpRequestMessage _httpRequestMessage;
MemoryStream _memoryStream;
StreamWriter _streamWriter;
StreamContent _streamContent;
HttpClient _client;
HttpResponseMessage _httpResponse;
//Initilize a HttpRequest Message
_httpRequestMessage =
new HttpRequestMessage();
//Set the end point
//You could also do this in the intilization
_httpRequestMessage.RequestUri =
new Uri(uri_parameter);
//Set your headers
_httpRequestMessage.Headers.Add("Accept", "application/xml");
_httpRequestMessage.Headers.Add("Content-Type", "application/xml");
//Set the methood
_httpRequestMessage.Method =
HttpMethod.Post;
//I'm asuming you want it to be async
Task.Run(async()=>{
//Set up the stream
using(_memoryStream = new MemoryStream()){
using(_streamWriter = new StreamWriter(_memoryStream)){
_streamWriter.Write(data_parameter);
_streamWriter.Flush();
_memoryStream.Seek(
offset:0,
loc: System.IO.SeekOrigin.Begin
);
using(_streamContent = new StreamContent(_memoryStream)){
_httpRequestMessage.Content = _streamContent;
_client =
new HttpClient();
try{
//Use the client to send your message
//Configure what you want back via completion option
using(_httpResponse = await _client.SendAsync(
request: _httpRequestMessage,
completionOption: HttpCompletionOption.ResponseHeadersRead)){
//Or however you would like to make sure there was no error
_httpResponse.EnsureSuccessStatusCode();
//If you want the response as a string:
string _content = await _httpResponse.Content.ReadAsStringAsync();
//Or response in a stream:
using(Stream _responseStream = await _httpResponse.Content.ReadAsStreamAsync()){
}
}
}
catch(Exception){
//Handle your exception
}
}
}
}
});
}

HttpWebRequest returns (400) Bad Request

The request gives the following error:
The remote server returned an error: (400) Bad Request.
I cann't find a solution on internet. Does anyone knows how to solve this?
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(#"https://maps.googleapis.com/maps/api/geocode/json");
request.ContentType = "application/x-www-form-urlencoded";
request.Method = "POST";
var parameters = string.Format("language={0}&latlng={1}&client={2}&signature={3}", "nl", "51.123456,5.612345", "gme-aa", "******_******=");
byte[] byteArray = Encoding.UTF8.GetBytes(parameters);
request.ContentLength = byteArray.Length;
Stream dataStream = request.GetRequestStream();
dataStream.Write(byteArray, 0, byteArray.Length);
dataStream.Close();
/*
* Read HttpWeb Response
*/
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
dataStream = response.GetResponseStream();
StreamReader reader = new StreamReader(dataStream);
string Response = reader.ReadToEnd();
response.Close();
EDIT:
I'm working inside Lowcode platform Outsystems. Outsystems creates the url inside WebRequest.Create() without the paramaters. So, I have access to webRequest object and need to pass the parameters.

You have to use HTTP "GET" Method.
In a GET request, you pass parameters as part of the query string.
HttpWebRequest request = (HttpWebRequest)WebRequest.Create($"https://maps.googleapis.com/maps/api/geocode/json?language=fr&latlng=51.123456,5.612345&key={apiKey}");
request.ContentType = "application/x-www-form-urlencoded";
request.Method = "GET";
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
string result = new StreamReader(response.GetResponseStream()).ReadToEnd();
}

According the documentation, the API is expecting a POST method and receiving the parameters in the URL and not the body.
If you are using the OutSystems platform you can use the Consume REST API functionality to easily call the web service without using code. Configure your API like this (you can copy the example JSON from the documentation page above):

Get Response from HttpWebRequest on Windows Phone 8

I'm trying to do a WebRequest to a site from a Windows Phone Application.
But is vry important for me to also get the response from the server.
Here is my code:
Uri requestUri = new Uri(string.Format("http://localhost:8099/hello/{0}", metodo));
HttpWebRequest httpWebRequest = (HttpWebRequest)WebRequest.Create(requestUri);
httpWebRequest.ContentType = "application/xml; charset=utf-8";
httpWebRequest.Method = "POST";
using (var stream = await Task.Factory.FromAsync<Stream>(httpWebRequest.BeginGetRequestStream,
httpWebRequest.EndGetRequestStream, null))
{
string xml = "<string xmlns=\"http://schemas.microsoft.com/2003/10/Serialization/\">Ahri</string>";
byte[] xmlAsBytes = Encoding.UTF8.GetBytes(xml);
await stream.WriteAsync(xmlAsBytes, 0, xmlAsBytes.Length);
}
Unfortunatelly, I have no idea of how I could get the response from the server.
Does anyone have an idea?
Thanks in advance.
Thanks to #max I found the solution and wanted to share it above.
Here is how my code looks like:
string xml = "<string xmlns=\"http://schemas.microsoft.com/2003/10/Serialization/\">Claor</string>";
Uri requestUri = new Uri(string.Format("http://localhost:8099/hello/{0}", metodo));
string responseFromServer = "no response";
HttpWebRequest httpWebRequest = HttpWebRequest.Create(requestUri) as HttpWebRequest;
httpWebRequest.ContentType = "application/xml; charset=utf-8";
httpWebRequest.Method = "POST";
using (Stream requestStream = await httpWebRequest.GetRequestStreamAsync())
{
byte[] xmlAsBytes = Encoding.UTF8.GetBytes(xml);
await requestStream.WriteAsync(xmlAsBytes, 0, xmlAsBytes.Length);
}
WebResponse webResponse = await httpWebRequest.GetResponseAsync();
using (var reader = new StreamReader(webResponse.GetResponseStream()))
{
responseFromServer = reader.ReadToEnd();
}
I hope it will help someone in the future.

This is very common question for people new in windows phone app
development. There are several sites which gives tutorials for the
same but I would want to give small answer here.
In windows phone 8 xaml/runtime you can do it by using HttpWebRequest or a WebClient.
Basically WebClient is a wraper around HttpWebRequest.
If you have a small request to make then user HttpWebRequest. It goes like this
HttpWebRequest request = HttpWebRequest.Create(requestURI) as HttpWebRequest;
WebResponse response = await request.GetResponseAsync();
using (var reader = new StreamReader(response.GetResponseStream()))
{
string responseContent = reader.ReadToEnd();
// Do anything with you content. Convert it to xml, json or anything.
}
Although this is a get request and i see that you want to do a post request, you have to modify a few steps to achieve that.
Visit this place for post request.
If you want windows phone tutorials, you can go here. He writes awesome tuts.

rest api is not giving desired results

I am not getting the results that documentation says. I login the Buddy; created application; copy this URL and assign to url string; when I execute the program I am not getting results that are expected (status + Accesstoken) as documentation says. Can anyone please tell me if I am missing something as newbie to http calls. Its running on http requester but not on Poster firefox add-on!
Documentation
http://dev.buddyplatform.com/Home/Docs/Getting%20Started%20-%20REST/HTTP?
Code
string parameters = "{appid:'xxxxxx', appkey: 'xxxxxxx', platform: 'REST Client'}";
private async void SimpleRequest()
{
HttpWebRequest request = null;
HttpWebResponse response = null;
try
{
request = (HttpWebRequest)WebRequest.Create(url);
request.Accept = "application/json";
request.ContentType = "application/json";
request.Method = "POST";
StreamWriter sw = new StreamWriter(await request.GetRequestStreamAsync());
sw.WriteLine(parameters);
sw.Close();
response = (HttpWebResponse) await request.GetResponseAsync();
}
catch (Exception)
{ }
}

Using the HTTP requester add-on on Firefox, I successfully retrieved an access token so their API work.
In C# they provide a line of code to submit your appid and appkey, that might be the problem :
Buddy.Init("yourAppId", "yourAppKey");
My guess is you have to use their .NET SDK!

You can certainly use the REST API from raw REST the way you're doing, though the .NET SDK will handle some of the more complex details of changing service root. I ran your code using my own Buddy credentials and I was able to get JSON containing an Access Token back. You may need to read the response stream back as JSON to retrieve the access token. I used the following code to dump the JSON to the console:
request = (HttpWebRequest)WebRequest.Create(url);
request.Accept = "application/json";
request.ContentType = "application/json";
request.Method = "POST";
StreamWriter sw = new StreamWriter(await request.GetRequestStreamAsync());
sw.WriteLine(parameters);
sw.Close();
response = (HttpWebResponse)await request.GetResponseAsync();
Console.WriteLine(await new StreamReader(response.GetResponseStream()).ReadToEndAsync());
Using Newtonsoft.Json I can parse out my accessToken like this:
Uri url = new Uri("https://api.buddyplatform.com/devices");
request = (HttpWebRequest)WebRequest.Create(url);
request.Accept = "application/json";
request.ContentType = "application/json";
request.Method = "POST";
StreamWriter sw = new StreamWriter(await request.GetRequestStreamAsync());
sw.WriteLine(parameters);
sw.Close();
response = (HttpWebResponse)await request.GetResponseAsync();
var parsed = JsonConvert.DeserializeObject<IDictionary<string,object>>( (await new StreamReader(response.GetResponseStream()).ReadToEndAsync()));
var accessToken = (parsed["result"] as JObject).GetValue("accessToken").ToString();
Console.WriteLine(accessToken);
The 3.0 SDK does all of this for you while exposing the rest of the service through a thin REST wrapper, the migration guide for the 3.0 SDK should help with this.

HTTP POST in .NET doesn't work

I've got a problem with creating an HTTP post request in .NET. When I do this request in ruby it does work.
When doing the request in .NET I get following error:
<h1>FOXISAPI call failed</h1><p><b>Progid is:</b> carejobs.carejobs
<p><b>Method is:</b> importvacature/
<p><b>Parameters are:</b>
<p><b> parameters are:</b> vacature.deelnemernr=478
</b><p><b>GetIDsOfNames failed with err code 80020006: Unknown name.
</b>
Does anyone knows how to fix this?
Ruby:
require 'net/http'
url = URI.parse('http://www.carejobs.be/scripts/foxisapi.dll/carejobs.carejobs.importvacature')
post_args = {
'vacature.deelnemernr' => '478',
}
resp, data = Net::HTTP.post_form(url, post_args)
print resp
print data
C#:
Uri address = new Uri(url);
// Create the web request
HttpWebRequest request = WebRequest.Create(address) as HttpWebRequest;
// Set type to POST
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
// Create the data we want to send
StringBuilder data = new StringBuilder();
data.Append("vacature.deelnemernr=" + HttpUtility.UrlEncode("478"));
// Create a byte array of the data we want to send
byte[] byteData = UTF8Encoding.UTF8.GetBytes(data.ToString());
// Set the content length in the request headers
request.ContentLength = byteData.Length;
// Write data
using (Stream postStream = request.GetRequestStream())
{
postStream.Write(byteData, 0, byteData.Length);
}
// Get response
using (HttpWebResponse response = request.GetResponse() as HttpWebResponse)
{
// Get the response stream
StreamReader reader = new StreamReader(response.GetResponseStream());
// Console application output
result = reader.ReadToEnd();
}
return result;

Don't you need the ? after the URL in order to do a post with parameters? I think that Ruby hides this behind the scenes.

I found the problem! The url variable in the C# code was "http://www.carejobs.be/scripts/foxisapi.dll/carejobs.carejobs.importvacature/"
It had to be "http://www.carejobs.be/scripts/foxisapi.dll/carejobs.carejobs.importvacature" without the backslash.