string clientId = _configuration["GoogleAPISettingsAuth:client_id"];
string clientSecret = _configuration["GoogleAPISettingsAuth:client_secret"];
string redirectUrl = _configuration["GoogleAPISettingsAuth:redirect_url"];
http.DefaultRequestHeaders.Clear();
string url = "
https://oauth2.googleapis.com/token";
url += "?code=" + code + "&client_id=" + clientId + "&client_secret=" + clientSecret;
url += "&redirect_uri=" + redirectUrl + "&grant_type=authorization_code";
http.DefaultRequestHeaders.Accept.Add(
new MediaTypeWithQualityHeaderValue("application/json"));
HttpResponseMessage httpResponse = await http.PostAsJsonAsync(url, new object());
string strResponse = httpResponse.Content.ReadAsStringAsync().Result;
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