How to call Rest API with Content and Headers in c#?

Question

I am trying to call Rest API with content and headers in c#. Actually I am trying to convert to c# from Python code which is:

import requests
url = 'http://url.../token'
payload = 'grant_type=password&username=username&password=password'
headers = {
  'Content-Type': 'application/x-www-form-urlencoded'
}
response = requests.request('POST', url, headers = headers, data = payload, allow_redirects=False)
print(response.text)

So far I am trying with:

HttpClient client = new HttpClient();
client.BaseAddress = new Uri(Url);

var tmp = new HttpRequestMessage
{
    Method = HttpMethod.Post,
    Content =
            {

            }
     };

    var result = client.PostAsync(Url, tmp.Content).Result;
}

I have no idea how to put from Python code Headers (Content-Type) and additional string (payload).

I gave you an answer based on HttpClient. Please check. – Jonathan Alfaro Mar 25 '19 at 04:39 — Jonathan Alfaro, Mar 25 '19 at 04:39

score 3 · Answer 1 · answered Mar 24 '19 at 14:33

If you use RestSharp, you should be able to call your service with the following code snipped

var client = new RestClient("http://url.../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&username=username&password=password", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
var result = response.Content;

I based my answer on the anwser of this answer.

score 3 · Accepted Answer · edited Jan 30 '21 at 21:45

3

Here a sample I use in one of my apps:

_client = new HttpClient { BaseAddress = new Uri(ConfigManager.Api.BaseUrl), 
                           Timeout = new TimeSpan(0, 0, 0, 0, -1) };

_client.DefaultRequestHeaders.Accept.Clear();
_client.DefaultRequestHeaders.Accept.Add(
                     new MediaTypeWithQualityHeaderValue("application/json"));
_client.DefaultRequestHeaders.Add("Bearer", "some token goes here");

edited Jan 30 '21 at 21:45

ΩmegaMan

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answered Mar 25 '19 at 04:38

Jonathan Alfaro

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Yes something like this, how did you solve setting like timeout=undefined and allow_redirects=False – DaniKR Mar 25 '19 at 08:22
@DaniKR like this: _client = new HttpClient { BaseAddress = new Uri(ConfigManager.Api.BaseUrl), Timeout = new TimeSpan(0, 0, 0, 0, -1) }; – Jonathan Alfaro Mar 25 '19 at 14:00
Just specify the timeout you want – Jonathan Alfaro Mar 25 '19 at 14:01

shingo · Answer 3 · 2019-03-25T03:14:10.547

using System.Net.Http;

var content = new StringContent("grant_type=password&username=username&password=password");
content.Headers.Add("Content-Type", "application/x-www-form-urlencoded");
client.PostAsync(Url, content);

Or use FormUrlEncodedContent without set header

var data = new Dictionary<string, string>
{
    {"grant_type", "password"},
    {"username", "username"},
    {"password", "password"}
};
var content = new FormUrlEncodedContent(data);
client.PostAsync(Url, content);

If you write UWP application, use HttpStringContent or HttpFormUrlEncodedContent instead in Windows.Web.Http.dll.

using Windows.Web.Http;

var content = new HttpStringContent("grant_type=password&username=username&password=password");
content.Headers.Add("Content-Type", "application/x-www-form-urlencoded");
client.PostAsync(Url, content);

var data = new Dictionary<string, string>
{
    {"grant_type", "password"},
    {"username", "username"},
    {"password", "password"}
};
var content = new FormUrlEncodedContent(data);
client.PostAsync(Url, content);

What reference I have to use for "HttpFormUrlEncodeContent"? — DaniKR, Mar 24 '19 at 14:51
Windows.Web.Http.dll. I've also add code for normal .net api. — shingo, Mar 25 '19 at 03:14
You made it look as though you can't specify your data and headers at the same time. That is not correct. — Jhourlad Estrella, May 25 '20 at 09:48

How to call Rest API with Content and Headers in c#?

3 Answers3