public static string Api_Post(string postUrl, string postData, WebHeaderCollection header = null,bool isPic=false)　　　　　{      Stream outstream = null;      Stream instream = null;      StreamReader sr = null;      HttpWebResponse response = null;      HttpWebRequest request = null;      Encoding encoding = Encoding.UTF8;      byte[] data = encoding.GetBytes(postData);      // 準備請求...      try      {        // 設置參數        request = WebRequest.Create(postUrl) as HttpWebRequest;        CookieContainer cookieContainer = new CookieContainer();        request.CookieContainer = cookieContainer;        request.AllowAutoRedirect = true;        request.Method = "POST";        request.ContentType = "application/x-www-form-urlencoded";        if (header != null) request.Headers = header;        request.ContentLength = data.Length;        outstream = request.GetRequestStream();        outstream.Write(data, 0, data.Length);        outstream.Close();        //發送請求并獲取相應回應數據        response = request.GetResponse() as HttpWebResponse;        //直到request.GetResponse()程序才開始向目標網頁發送Post請求        instream = response.GetResponseStream();        if (isPic)        {          byte[] tt = StreamToBytes(instream);//將數據流轉為byte[]          System.IO.File.WriteAllBytes(HttpContext.Current.Server.MapPath("~/WxCode.jpg"), tt);          WxQRCodeModel model = new WxQRCodeModel();          model.data = "192.168.1.216:80/WxCode.jpg";          model.errcode = 0;          string content = Config.js.Serialize(model);          string err = string.Empty;          return content;        }        else        {          sr = new StreamReader(instream, encoding);          //返回結果網頁（html）代碼          string content = sr.ReadToEnd();          string err = string.Empty;          return content;        }      }      catch (Exception ex)      {        if (isPic)        {          sr = new StreamReader(instream, encoding);          //返回結果網頁（html）代碼          string content = sr.ReadToEnd();          string err = string.Empty;          return content;        }        else        {          string err = ex.Message;          return string.Empty;        }      }    }

    ///將數據流轉為byte[]    public static byte[] StreamToBytes(Stream stream)    {      List<byte> bytes = new List<byte>();      int temp = stream.ReadByte();      while (temp != -1)      {        bytes.Add((byte)temp);        temp = stream.ReadByte();      }      return bytes.ToArray();    }