HTTP请求

        string url = https://xxx.xxxx.com/Services/Login.ashx;
        string json = "";
        Encoding encoding = Encoding.UTF8;
        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
        request.Method = "post";
        request.Headers.Add("Method", context.Request.Headers["Method"]);
        request.Headers.Add("timespan", context.Request.Headers["Timespan"]);
        request.Headers.Add("Nonce", context.Request.Headers["Nonce"]);
        request.Headers.Add("Token", context.Request.Headers["Token"]);
        request.Headers.Add("Account", System.Web.HttpUtility.UrlDecode(context.Request.Headers["Account"]));
        request.Headers.Add("Source", context.Request.Headers["Source"]);
        request.Headers.Add("Version", context.Request.Headers["Version"]);
        request.Headers.Add("Sign", context.Request.Headers["Sign"]);


        request.Accept = "text/html, application/xhtml+xml, */*";
        request.ContentType = "application/x-www-form-urlencoded";
        byte[] buffer = encoding.GetBytes(RequestString.ToString());
        request.ContentLength = buffer.Length;
        request.GetRequestStream().Write(buffer, 0, buffer.Length);
        HttpWebResponse response = (HttpWebResponse)request.GetResponse();
        using (StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.UTF8))
        {
            json = reader.ReadToEnd();
        }

            var url = "https://oauth.wanxiangyun.net/open/token";
            var client = new HttpClient();

            List<KeyValuePair<string, string>> parameters = new List<KeyValuePair<string, string>>();

            KeyValuePair<string, string> bnvp1 = new KeyValuePair<string, string>("client_id", BaseConfig.client_id);
            KeyValuePair<string, string> bnvp2 = new KeyValuePair<string, string>("client_secret", BaseConfig.client_secret);
            KeyValuePair<string, string> bnvp3 = new KeyValuePair<string, string>("grant_type", "client_credentials");
            parameters.Add(bnvp1);
            parameters.Add(bnvp2);
            parameters.Add(bnvp3);
            var builder = new StringBuilder();
            var result = client.PostAsync(url, new FormUrlEncodedContent(parameters)).Result;
            return DynamicJson.Parse(result.Content.ReadAsStringAsync().Result);