oAuth2.0 登录新浪微博 发送新浪微博 代码

public class SinaoAuth
    {
        string APIHost = "";
        public SinaoAuth() 
        {
            APIHost = SinaConfig.Sina_Host;
        }

        #region 绑定微博帐号
        /// <summary>
        /// 绑定微博帐号
        /// </summary>
        /// <param name="username">新浪微博的登录帐号</param>
        /// <param name="password">新浪微博的登录密码</param>
        /// <returns>失败返回null</returns>
        public string Binding(String username, String password)
        {
            if (String.IsNullOrEmpty(username) || String.IsNullOrEmpty(password))
            {
                return null;
            }
            string apiUrl = "https://api.weibo.com/oauth2/access_token?client_id=" + SinaConfig.Sina_AppKey + "&client_secret=" + SinaConfig.Sina_AppSecurity + "&grant_type=password&username=" + username + "&password=" + password;

            try
            {
                HttpWebRequest webReq = (HttpWebRequest)HttpWebRequest.Create(apiUrl);
                webReq.Method = "POST";
                webReq.Timeout = 2000;
                //webReq.Headers.Add("Authorization", header);
                HttpWebResponse webRsp = (HttpWebResponse)webReq.GetResponse();

                using (StreamReader reader = new StreamReader(webRsp.GetResponseStream()))
                {
                    string rsp = reader.ReadToEnd();
                    AccessTokenResponse accessToken = new AccessTokenResponse(rsp);
                    if (accessToken != null && accessToken.IsValid)
                    {
                        return accessToken.AccessToken;
                    }
                    else
                    {
                        return null;
                    }
                }
            }
            catch (WebException e)
            {
                return GetErrorMessage(e);
            }
        }

        private string GetErrorMessage(WebException e) 
        {
            try
            {
                HttpWebResponse webResponse = e.Response as HttpWebResponse;
                StreamReader myread = new StreamReader(webResponse.GetResponseStream());
                string error = myread.ReadToEnd();
                ErrorMessage errorMessage = new ErrorMessage(error);
                return errorMessage.Error_code;
            }
            catch (Exception ex)
            {
                return ex.Message;
                throw;
            }
        }

        /// <summary>
        /// 用web方式登录
        /// </summary>
        /// <param name="code"></param>
        /// <returns></returns>
        public string Binding(string code)
        {
            string apiUrl = "https://api.weibo.com/oauth2/access_token?client_id="+SinaConfig.Sina_AppKey+"&client_secret="+
                SinaConfig.Sina_AppSecurity + "&grant_type=authorization_code&redirect_uri=http://sae.sina.com.cn/&code="+code;
            try
            {
                HttpWebRequest webReq = (HttpWebRequest)HttpWebRequest.Create(apiUrl);
                webReq.Method = "POST";
                webReq.Timeout = 2000;
                //webReq.Headers.Add("Authorization", header);
                HttpWebResponse webRsp = (HttpWebResponse)webReq.GetResponse();

                using (StreamReader reader = new StreamReader(webRsp.GetResponseStream()))
                {
                    string rsp = reader.ReadToEnd();
                    AccessTokenResponse accessToken = new AccessTokenResponse(rsp);
                    if (accessToken != null && accessToken.IsValid)
                    {
                        return accessToken.AccessToken;
                    }
                    else
                    {
                        return null;
                    }
                }
            }
            catch (WebException e)
            {
                return GetErrorMessage(e);
            }
        }

        /// <summary>
        /// 直接发送微博
        /// </summary>
        /// <param name="access_token"></param>
        /// <param name="status"></param>
        /// <returns></returns>
        public string update(string access_token,string status) 
        {
            string apiUrl = "https://api.weibo.com/2/statuses/update.json";
            try
            {
                HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(apiUrl);
                request.Method = "POST";
                request.Timeout = 2000;               
                request.ContentType = "application/x-www-form-urlencoded";
                System.Text.Encoding encoding = System.Text.Encoding.ASCII;
                byte[] bytesToPost = encoding.GetBytes("access_token=" + access_token + "&status=" + UrlEncode(status));
                request.ContentLength = bytesToPost.Length;
                System.IO.Stream requestStream = request.GetRequestStream();
                requestStream.Write(bytesToPost, 0, bytesToPost.Length);
                requestStream.Close();

                HttpWebResponse response = (HttpWebResponse)request.GetResponse();
                using (StreamReader reader = new StreamReader(response.GetResponseStream()))
                {
                    string rsp = reader.ReadToEnd();
                    if (rsp != "")
                    {
                        return "SUCCESS";
                    }
                }
                return null;
            }
            catch (WebException ex)
            {
                return GetErrorMessage(ex);
            }
        }

        public static string UrlEncode(string str)
        {
            StringBuilder sb = new StringBuilder();
            byte[] byStr = System.Text.Encoding.UTF8.GetBytes(str); //默认是System.Text.Encoding.Default.GetBytes(str)
            for (int i = 0; i < byStr.Length; i++)
            {
                sb.Append(@"%" + Convert.ToString(byStr[i], 16));
            }

            return (sb.ToString());
        }

        /// <summary>
        /// 发送带图片的微博
        /// </summary>
        /// <param name="access_token"></param>
        /// <param name="status">文字内容</param>
        /// <param name="pic">图片的byte流</param>
        /// <returns></returns>
        public string ShareImg(string access_token,string status,byte[] pic) 
        {
            string apiUrl = "https://api.weibo.com/2/statuses/upload.json?access_token=" + access_token + "&status=" +UrlEncode(status) + "&pic=" + @pic + "";
            
            try
            {
                HttpWebRequest webReq = (HttpWebRequest)HttpWebRequest.Create(apiUrl);
                webReq.Method = "POST";
                webReq.Timeout = 2000; 
                string boundary = Guid.NewGuid().ToString();
                //webReq.ContentType = string.Format("text/html; charset=GBK");
                webReq.ContentType=string.Format("multipart/form-data; boundary={0}", boundary);
                byte[] contents = getMultipartContent(status, pic, boundary);
                webReq.ContentLength = contents.Length;
                webReq.GetRequestStream().Write(contents, 0, contents.Length);

                HttpWebResponse webRsp = (HttpWebResponse)webReq.GetResponse();

                using (StreamReader reader = new StreamReader(webRsp.GetResponseStream()))
                {
                    string rsp = reader.ReadToEnd();
                    if (rsp != "")
                    {
                        return "SUCCESS";
                    }
                }
                return null;
            }
            catch (WebException e)
            {
                return GetErrorMessage(e);
            }
        }


        private byte[] getMultipartContent(string msg, byte[] pic, string boundary)
        {
            string contentEncoding = "iso-8859-1";
            string header = string.Format("--{0}", boundary);
            string footer = string.Format("--{0}--", boundary);

            StringBuilder contents = new StringBuilder();
            contents.AppendLine(header);
            contents.AppendLine(String.Format("Content-Disposition: form-data; name=\"{0}\"", "status"));
            contents.AppendLine("Content-Type: text/plain;  charset=US-ASCII");
            contents.AppendLine("Content-Transfer-Encoding: 8bit");
            contents.AppendLine();
            contents.AppendLine(UrlEncode(msg));

            contents.AppendLine(header);
            contents.AppendLine(string.Format("Content-Disposition: form-data; name=\"{0}\"", "source"));
            contents.AppendLine("Content-Type: text/plain;  charset=US-ASCII");
            contents.AppendLine("Content-Transfer-Encoding: 8bit");
            contents.AppendLine();
            contents.AppendLine(SinaConfig.Sina_AppKey);

            contents.AppendLine(header);
            string fileHeader = string.Format("Content-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"", "pic", "");
            string fileData = System.Text.Encoding.GetEncoding(contentEncoding).GetString(pic);

            contents.AppendLine(fileHeader);
            contents.AppendLine("Content-Type: application/octet-stream; charset=UTF-8");
            contents.AppendLine("Content-Transfer-Encoding: binary");
            contents.AppendLine();
            contents.AppendLine(fileData);
            contents.AppendLine(footer);

            return Encoding.GetEncoding(contentEncoding).GetBytes(contents.ToString());
        }

        #endregion
    }

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