private static string GetDevDefinedOAuthHeader(string consumerKey, string consumerSecret, string accessToken, string accessTokenSecret, HttpWebRequest webRequest, string requestBody) { OAuthConsumerContext consumerContext = new OAuthConsumerContext { ConsumerKey = consumerKey, SignatureMethod = SignatureMethod.HmacSha1, ConsumerSecret = consumerSecret, UseHeaderForOAuthParameters = true }; //We already have OAuth tokens, so OAuth URIs below are not used - set to example.com OAuthSession oSession = new OAuthSession(consumerContext, "https://www.example.com", "https://www.example.com", "https://www.example.com"); oSession.AccessToken = new TokenBase { Token = accessToken, ConsumerKey = consumerKey, TokenSecret = accessTokenSecret }; IConsumerRequest consumerRequest = oSession.Request(); consumerRequest = ConsumerRequestExtensions.ForMethod(consumerRequest, webRequest.Method); if (requestBody != null) { consumerRequest = consumerRequest.Post().WithRawContentType(webRequest.ContentType).WithRawContent(System.Text.Encoding.ASCII.GetBytes(requestBody)); } consumerRequest = ConsumerRequestExtensions.ForUri(consumerRequest, webRequest.RequestUri); consumerRequest = consumerRequest.SignWithToken(); return(consumerRequest.Context.GenerateOAuthParametersForHeader()); }