Develop Reference

Send JSON data in http post request C#

I'm trying to send a http post request in JSON format which should look like this:
{
"id":"72832",
"name":"John"
}
I have attempted to do it like below but if I am correct this is not sending a request in json format.
var values = new Dictionary<string,string>
{
{"id","72832"},
{"name","John"}
};
using (HttpClient client = new HttpClient())
{
var content = new FormUrlEncodedContent(values);
HttpResponseMessage response = await client.PostAsync("https://myurl",content);
// code to do something with response
}
How could I modify the code to send the request in json format?

try this
using (var client = new HttpClient())
{
var contentType = new MediaTypeWithQualityHeaderValue("application/json");
var baseAddress = "https://....";
var api = "/controller/action";
client.BaseAddress = new Uri(baseAddress);
client.DefaultRequestHeaders.Accept.Add(contentType);
var data = new Dictionary<string,string>
{
{"id","72832"},
{"name","John"}
};
var jsonData = JsonConvert.SerializeObject(data);
var contentData = new StringContent(jsonData, Encoding.UTF8, "application/json");
var response = await client.PostAsync(api, contentData);
if (response.IsSuccessStatusCode)
{
var stringData = await response.Content.ReadAsStringAsync();
var result = JsonConvert.DeserializeObject<object>(stringData);
}
}
Update
If the request comes back with Json data in the form `
{ "return":"8.00", "name":"John" }
you have to create result model
public class ResultModel
{
public string Name {get; set;}
public double Return {get; set;}
}
and code will be
if (response.IsSuccessStatusCode)
{
var stringData = await response.Content.ReadAsStringAsync();
var result = JsonConvert.DeserializeObject<ResultModel>(stringData);
var value=result.Return;
var name=Result.Name;
}

I would start off by using RestSharp.
dotnet add package RestSharp
Then you can send requests like this:
public async Task<IRestResult> PostAsync(string url, object body)
{
var client = new RestClient(url);
client.Timeout = -1;
var request = new RestRequest(Method.Post);
request.AddJsonBody(body);
var response = await client.ExecuteAsync(request);
return response;
}
Just pass in your dictionary as the body object - I would recommend creating a DTOS class to send through though.
Then you can get certain aspects of the RestResponse object that is returned like:
var returnContent = response.Content;
var statusCode = response.StatusCode;

Xamarin Sending POST Data

I am attempting to send POST data to my server and get back a response. For some reason, no POST data is actually getting sent. A request is being sent to my server but the POST array is empty.
Here is my code for sending the request:
public class GlobalMethods
{
public async Task<string> callAjax(string mthd,NameValueCollection parameters)
{
var client = new HttpClient();
var content = JsonConvert.SerializeObject(parameters);
var result = await client.PostAsync("http://dev.adex-intl.com/adex/mvc/receiving/"+mthd, new StringContent(content)).ConfigureAwait(false);
var tokenJson = "";
if (result.IsSuccessStatusCode)
{
tokenJson = await result.Content.ReadAsStringAsync();
}
return tokenJson;
}
}
And here is my code that calls the above method:
public void loginPressed(object sender, EventArgs e)
{
if(String.IsNullOrEmpty(badge.Text)) {
DisplayAlert("Error", "Enter your badge number", "Ok");
} else {
IsBusy = true;
NameValueCollection parameters = new NameValueCollection();
parameters["badgetNumber"] = badge.Text;
GlobalMethods globalMethods = new GlobalMethods();
var results = globalMethods.callAjax("login", parameters);
}
}
I'm not sure what I'm doing wrong. Also, I'm a newbie to Xamarin and C# so I'm not even sure if the way I am attempting to do things is the best way.

You haven't specify the type of content that you want to send, in your case it's 'application/json', you can set it like that:
"var client = new HttpClient();
var content = new StringContent(JsonConvert.SerializeObject(parameters));
content.Headers.ContentType = new MediaTypeHeaderValue("application/json");". Also, I would suggest you to write code like that:
var uri = new Uri(url);
using (var body = new StringContent(JsonConvert.SerializeObject(data)))
{
body.Headers.ContentType = new MediaTypeHeaderValue("application/json");
var request = new HttpRequestMessage
{
Version = new Version(1, 0),
Content = body,
Method = HttpMethod.Post,
RequestUri = uri
};
try
{
using (var response = await _client.SendAsync(request,cancellationToken))
{
if (response.IsSuccessStatusCode)
{
//Deal with success response
}
else
{
//Deal with non-success response
}
}
}
catch(Exception ex)
{
//Deal with exception.
}
}

You can use PostAsync for async sending data to server. your code should be something like this:
HttpClient client = new HttpClient();
var values = new Dictionary<string, string>
{
{ "p1", "data1" },
{ "p2", "data2" }
};
var content = new FormUrlEncodedContent(values);
var response = await client.PostAsync("http://www.example.com/index.php", content);
var responseString = await response.Content.ReadAsStringAsync();

How to Return the HTTP Call Response in C#

I am trying to return the response of productRating in this HTTP call. I have tried several ways but haven't been successful. Any idea? The response is a json with an object that I want to get access to the streamInfo>avgRatings>_overall
public double GetRatings(string productId)
{
const string URL = "https://comments.au1.gigya.com/comments.getStreamInfo";
var apiKey = "3_rktwTlLYzPlqkzS62-OxNjRDx8jYs-kV40k822YlHfEx5VCu93fpUo8JtaKDm_i-";
var categoryId = "product-ratings";
var urlParams = "?apiKey=" + apiKey + "&categoryID=" + categoryId + "&streamID=" + productId + "";
HttpClient client = new HttpClient();
client.BaseAddress = new Uri(URL);
client.DefaultRequestHeaders.Accept.Add(
new MediaTypeWithQualityHeaderValue("application/json"));
var response = JsonConvert.DeserializeObject(client.GetAsync(urlParams).Result.Content.ReadAsStringAsync().Result);
var productrating = (response["streamInfo"]["avgRatings"]["_overall"]);
return;
}
GetRatings Erroe: not all code paths return a value.
Productrating Error:can not apply indexing with [] to an expression of type HttpResponseMessage
return Error: an object of a type convertable to double is required

ApiCall has to return something. Looking at the example below.
#functions {
public static string ApiCall()
{
return "Hello World!";
}
}
#{
var ratings = ApiCall();
}
#if (ratings != null)
{
<div class="gig-rating-stars" content=#ratings></div>
}

I am using this function for POST API Call and it returns response string and if you want to add security features you can send it in JObject because its the secure channel to send Jobject as a parameter on URL
## Code Start ##
protected string RemoteApiCallPOST(JObject elements, string url)
{
try
{
var httpWebRequest = (HttpWebRequest)WebRequest.Create(url);
httpWebRequest.ContentType = "application/json";
httpWebRequest.Method = "POST";
// JObject jsonResult = new JObject();
string id;
using (var streamWriter = new StreamWriter(httpWebRequest.GetRequestStream()))
{
streamWriter.Write(elements);
streamWriter.Flush();
streamWriter.Close();
}
var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();
using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
{
id = (streamReader.ReadToEnd()).ToString();
return id;
}
}
catch (Exception EX)
{
return "";
}
}
Code End

The only change I needed to do is changing "var" to "dynamic" in :
dynamic response = JsonConvert.DeserializeObject(client.GetAsync(urlParams).Result.Content.ReadAsStringAsync().Result);

RestSharp post request - Body with x-www-form-urlencoded values

I am using postman and making an api post request where I am adding body with x-www-form-urlencoded key/values and it works fine in postman.
The issue arrises when I try it from c# using RestSharp package.
I have tried the following code below but not getting the response. I get "BadRequest" invalid_client error.
public class ClientConfig {
public string client_id { get; set; } = "value here";
public string grant_type { get; set; } = "value here";
public string client_secret { get; set; } = "value here";
public string scope { get; set; } = "value here";
public string response_type { get; set; } = "value here";
}
public void GetResponse() {
var client = new RestClient("api-url-here");
var req = new RestRequest("endpoint-here",Method.POST);
var config = new ClientConfig();//values to pass in request
req.AddHeader("Content-Type","application/x-www-form-urlencoded");
req.AddParameter("application/x-www-form-urlencoded",config,ParameterType.RequestBody);
var res = client.Execute(req);
return;
}
//Also tried this
req.AddParameter("client_id",config.client_id,"application/x-www-form-urlencoded",ParameterType.RequestBody);
req.AddParameter("grant_type",config.grant_type,"application/x-www-form-urlencoded",ParameterType.RequestBody);
req.AddParameter("client_secret",config.client_secret,"application/x-www-form-urlencoded",ParameterType.RequestBody);
req.AddParameter("scope",config.scope,ParameterType.RequestBody);
req.AddParameter("response_type",config.response_type,"application/x-www-form-urlencoded",ParameterType.RequestBody);
//tried this too
var client = new RestClient("url-here");
var req = new RestRequest("endpointhere",Method.POST);
var config = new ClientConfig();
req.AddBody(config);
var res = client.Execute(req);

this working for me, it was generator from postman
var token = new TokenValidation()
{
app_id = CloudConfigurationManager.GetSetting("appId"),
secret = CloudConfigurationManager.GetSetting("secret"),
grant_type = CloudConfigurationManager.GetSetting("grant_type"),
Username = CloudConfigurationManager.GetSetting("Username"),
Password = CloudConfigurationManager.GetSetting("Password"),
};
var client = new RestClient($"{xxx}{tokenEndPoint}");
var request = new RestRequest(Method.POST);
request.AddHeader("content-type", "application/x-www-form-urlencoded");
request.AddParameter("application/x-www-form-urlencoded", $"app_id={token.app_id}&secret={token.secret}&grant_type={token.grant_type}&Username={token.Username}&Password={token.Password}", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
if (response.StatusCode != HttpStatusCode.OK)
{
Console.WriteLine("Access Token cannot obtain, process terminate");
return null;
}
var tokenResponse = JsonConvert.DeserializeObject<TokenValidationResponse>(response.Content);

I personally find this way to work better for me when sending Form-UrlEncoded data.
public void GetResponse() {
var client = new RestClient("api-url-here");
var req = new RestRequest("endpoint-here",Method.POST);
var config = new ClientConfig();//values to pass in request
// Content type is not required when adding parameters this way
// This will also automatically UrlEncode the values
req.AddParameter("client_id",config.client_id, ParameterType.GetOrPost);
req.AddParameter("grant_type",config.grant_type, ParameterType.GetOrPost);
req.AddParameter("client_secret",config.client_secret, ParameterType.GetOrPost);
req.AddParameter("scope",config.scope, ParameterType.GetOrPost);
req.AddParameter("response_type",config.response_type, ParameterType.GetOrPost);
var res = client.Execute(req);
return;
}
Details on this parameter type can be found here:
https://github.com/restsharp/RestSharp/wiki/ParameterTypes-for-RestRequest#getorpost

Personally, I found AddObject() method quite useful, and cleaner when you have so many parameters to add.
public void GetResponse() {
var client = new RestClient("api-url-here");
var req = new RestRequest("endpoint-here",Method.POST);
var config = new ClientConfig();//values to pass in request
req.AddHeader("Content-Type","application/x-www-form-urlencoded");
req.AddObject(config);
var res = client.Execute(req);
return res;
}

If it worked on postman, you can just press the code button on the right hand side. This will provide a working example in multiple languages. It is the button above the information icon. I would post a screenshot of it, but I don't have 10 reputation to do so.

i have found this good for my scenario , it is working perfect,
var client = new RestClient("https://test.salesforce.com/services/oauth2/token");
var request = new RestRequest(Method.POST);
request.AddHeader("content-type", "application/x-www-form-urlencoded");
request.AddParameter("application/x-www-form-urlencoded", "grant_type=password&client_id=3MVG9U_dUptXGpYKew7P.oPwrIsvowP_K4CsnkxHJIEOUJzW0XBUUY3o12bLDasjeIPGVobvBZo8TNFcCY6J3&client_secret=3189542819149073716&username=integraciones%40lamarina.com.mx.dev&password=2Password!4iwZvMQKVAwkYyJRy50JlAHk", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
Console.WriteLine("Response.StatusCode: " + response.StatusCode);
Console.WriteLine("Response.Content: " + response.Content);
Console.WriteLine("Response.ErrorMessage: " + response.ErrorMessage);
https://dotnetfiddle.net/J64FR5

in my case this is what worked
req.AddParameter("client_id", "unigen-corporation", ParameterType.HttpHeader);
req.AddParameter("grant_type", "client_credentials", ParameterType.GetOrPost);

If you've copied the code from the postman, try removing the following:
request.AlwaysMultipartFormData = true;
In my case after removing this line code worked.

var client1 = new RestClient(URI);
var request1 = new RestRequest(Method.POST);
request1.AddHeader("Content-Type", "application/x-www-form-urlencoded");
request1.AddParameter("client_id", "XX");
request1.AddParameter("client_secret", "XX");
request1.AddParameter("grant_type", "XX");
request1.AddParameter("role", "XX");
IRestResponse response1 = client1.Execute(request1);
System.Console.WriteLine(response1.Content);
Add parameters according to your needs. This work fine!

for my code, this works perfect.
// extention function for object->formed data body string
public static string toFormDataBodyString(this object src)
{
var res = new List<string>();
foreach (var key in src.GetType().GetProperties())
{
res.Add($"{key.Name}={src.GetType().GetProperty(key.Name)?.GetValue(src)}");
}
return string.Join("&", res);
}
//--------------------------------------
var data = new {
param1 = xxxx,
param2 = xxxx
}
var translateReq = new RestRequest("url_here")
.AddHeader("Content-Type", "application/x-www-form-urlencoded")
.AddParameter("application/x-www-form-urlencoded", data.toFormDataBodyString(), ParameterType.RequestBody);

Using a token to search on Twitter with OAuth2

Before Twitter switched to OAuth2, I was using the following query:
string atomTweetSearchURL = string.Format("http://search.twitter.com/search.atom?q={0}", searchText);
This no longer works, so now I'm trying to switch to OAuth2. I manage to successfully retrieve a token, but once I've got this, I seem to be unable to actually perform the search. Here's the latest incarnation of what I've tried:
var searchUrl = string.Format("https://api.twitter.com/1.1/search/tweets.json?q={0}&access_token={1}&token_type={2}", srchStr, twitAuthResponse.access_token, twitAuthResponse.token_type);
WebRequest srchRequest = WebRequest.Create(searchUrl);
using (var response2 = await srchRequest.GetResponseAsync())
{
Stream stream = response2.GetResponseStream();
using (StreamReader sr = new StreamReader(stream))
{
string jsonResponse = await sr.ReadToEndAsync();
}
}
This gives me a 400 - bad request.
I've also tried building the request like this:
System.Net.Http.HttpClient srchRequest = new System.Net.Http.HttpClient();
string authHdr = string.Format(srchHeaderFormat, twitAuthResponse.token_type, twitAuthResponse.access_token);
srchRequest.DefaultRequestHeaders.Add("Authorization", authHdr);
There's a massive quantity of articles out there detailing how to do this, but none of them seem to work correctly with WinRT. Can anyone point me in the right direction?
EDIT
Here's my code to get the token:
var oAuthConsumerKey = key;
var oAuthConsumerSecret = secret;
var oAuthUri = new Uri("https://api.twitter.com/oauth2/token");
var authHeaderFormat = "Basic {0}";
var authHeader = string.Format(authHeaderFormat,
Convert.ToBase64String(Encoding.UTF8.GetBytes(Uri.EscapeDataString(oAuthConsumerKey)
+ ":" +
Uri.EscapeDataString((oAuthConsumerSecret)))
));
var req = new HttpClient();
req.DefaultRequestHeaders.Add("Authorization", authHeader);
HttpRequestMessage msg = new HttpRequestMessage(new HttpMethod("POST"), oAuthUri);
msg.Content = new HttpStringContent("grant_type=client_credentials");
msg.Content.Headers.ContentType = new Windows.Web.Http.Headers.HttpMediaTypeHeaderValue("application/x-www-form-urlencoded");
HttpResponseMessage response = await req.SendRequestAsync(msg);
TwitAuthenticateResponse twitAuthResponse;
using (response)
{
string objectText = await response.Content.ReadAsStringAsync();
twitAuthResponse = JSonSerialiserHelper.Deserialize<TwitAuthenticateResponse>(objectText);
}

With the 1.1 API you don't pass the access token as part of the url, you need to include it as the Authorization header as "Bearer access_token" so you were almost there!
EDIT
To do this in the Windows.Web.Http namespace the following works:
private static async Task SearchTweets(AuthenticationResponse twitAuthResponse)
{
string srchStr = "tweet";
var client = new HttpClient();
var searchUrl = string.Format("https://api.twitter.com/1.1/search/tweets.json?q={0}", srchStr);
var uri = new Uri(searchUrl);
client.DefaultRequestHeaders.Authorization = new HttpCredentialsHeaderValue("Bearer", twitAuthResponse.AccessToken);
var response2 = await client.GetAsync(uri);
string content = await response2.Content.ReadAsStringAsync();
}
Or with System.Net.Http use the following:
This code will run the search for srchStr using the access token you already acquired as you showed in the first example:
var client = new HttpClient();
var searchUrl = string.Format("https://api.twitter.com/1.1/search/tweets.json?q={0}", srchStr);
var uri = new Uri(searchUrl);
client.DefaultRequestHeaders.Add("Authorization", string.Format("Bearer {0}", twitAuthResponse.access_token));
HttpResponseMessage response = await client.GetAsync(uri);
Task<string> content = response.Content.ReadAsStringAsync();
EDIT
This is a strange one, I tested your code and you're right it does throw an exception when attempting to add the Auth header, however the code I had used for grabbing the Access Token is almost identical but uses the System.Net.Http methods rather than the Windows.Web.Http ones that you use and it works, so I'll provide my code here, maybe this is a bug in the framework, or someone else can provide some more insight! This also uses the JSON.NET library which can be found on NuGet.
private static async Task SearchTweets(AuthenticationResponse twitAuthResponse)
{
string srchStr = "tweet";
var client = new HttpClient();
var searchUrl = string.Format("https://api.twitter.com/1.1/search/tweets.json?q={0}", srchStr);
var uri = new Uri(searchUrl);
client.DefaultRequestHeaders.Add("Authorization", string.Format("Bearer {0}", twitAuthResponse.AccessToken));
HttpResponseMessage response2 = await client.GetAsync(uri);
string content = await response2.Content.ReadAsStringAsync();
}
private async void GetAuthenticationToken()
{
var client = new HttpClient();
var uri = new Uri("https://api.twitter.com/oauth2/token");
var encodedConsumerKey = WebUtility.UrlEncode(TwitterConsumerKey);
var encodedConsumerSecret = WebUtility.UrlEncode(TwitterConsumerSecret);
var combinedKeys = String.Format("{0}:{1}", encodedConsumerKey, encodedConsumerSecret);
var utfBytes = System.Text.Encoding.UTF8.GetBytes(combinedKeys);
var encodedString = Convert.ToBase64String(utfBytes);
client.DefaultRequestHeaders.Add("Authorization", string.Format("Basic {0}", encodedString));
var data = new List<KeyValuePair<string, string>>
{
new KeyValuePair<string, string>("grant_type", "client_credentials")
};
var postData = new FormUrlEncodedContent(data);
var response = await client.PostAsync(uri, postData);
AuthenticationResponse authenticationResponse;
using (response)
{
if (response.StatusCode != System.Net.HttpStatusCode.OK)
throw new Exception("Did not work!");
var content = await response.Content.ReadAsStringAsync();
authenticationResponse = JsonConvert.DeserializeObject<AuthenticationResponse>(content);
if (authenticationResponse.TokenType != "bearer")
throw new Exception("wrong result type");
}
await SearchTweets(authenticationResponse);
}
}
class AuthenticationResponse
{
[JsonProperty("token_type")]
public string TokenType { get; set; }
[JsonProperty("access_token")]
public string AccessToken { get; set; }
}