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C#

Twitter - Application Only Authentication

Demonstrates how to get a Twitter OAuth2 token for application-only authentication.

This example is deprecated and no longer valid.

Chilkat C# Downloads

C#
bool success = false;

//  It requires the Chilkat API to have been previously unlocked.
//  See Global Unlock Sample for sample code.

//  Note: Define your Twitter apps at https://apps.twitter.com/

//  We're going to send an HTTPS POST that looks like this:

//  POST /oauth2/token HTTP/1.1
//  Host: api.twitter.com
//  User-Agent: My Twitter App v1.0.23
//  Authorization: Basic eHZ6MWV2RlM0d0VFUFRHRUZQSEJvZzpMOHFxOVBaeVJn
//                       NmllS0dFS2hab2xHQzB2SldMdzhpRUo4OERSZHlPZw==
//  Content-Type: application/x-www-form-urlencoded;charset=UTF-8
//  Content-Length: 29
//  Accept-Encoding: gzip
//  
//  grant_type=client_credentials

//  Update these values with your consumer key and secret (also known as API key and API secret).
string consumerKey = "TWITTER_CONSUMER_KEY";
string consumerSecret = "TWITTER_CONSUMER_SECRET";

Chilkat.Http http = new Chilkat.Http();

http.BasicAuth = true;
http.Login = consumerKey;
http.Password = consumerSecret;

Chilkat.HttpRequest req = new Chilkat.HttpRequest();
req.AddParam("grant_type","client_credentials");

req.HttpVerb = "POST";
req.ContentType = "application/x-www-form-urlencoded";

Chilkat.HttpResponse resp = new Chilkat.HttpResponse();
success = http.HttpReq("https://api.twitter.com/oauth2/token",req,resp);
if (success == false) {
    Debug.WriteLine(http.LastErrorText);
    return;
}

Debug.WriteLine("Response Status Code: " + Convert.ToString(resp.StatusCode));

if (resp.StatusCode != 200) {
    Debug.WriteLine("Expected a 200 response status code for success.");
    Debug.WriteLine(resp.BodyStr);
    return;
}

//  We should get a JSON response like this:

//  {
//      "token_type":"bearer",
//      "access_token":"..."
//  }

Chilkat.JsonObject json = new Chilkat.JsonObject();
json.Load(resp.BodyStr);

Debug.WriteLine("Access token = " + json.StringOf("access_token"));