.net c#后台请求接口

我们在请求接口的时候，有时因为跨域的问题，总是请求接口失败，亦或是请求接口时，页面还存在跳转的问题，这个时候，我们通过前台ajax请求自己的一般处理程序，用一般处理程序请求客户提供的接口

    //获取token
    public string gettoken(HttpContext context)
    {
       string strResult = "";
        try
        {
            string code = context.Request.QueryString["code"];
            string user = Convert.ToBase64String(System.Text.Encoding.UTF8.GetBytes("userName" + ":" + "pwd"));  //验证用户的身份，否则会报401(未授权)的错误，
            LogHelper.WriteLog(code);
            HttpWebRequest myRequest = (HttpWebRequest)WebRequest.Create("http://vcc.hbasesoft.com:8162/oauth/token?client_id=69D8274D631711E880ADDF64DF6ADFSD&code=" + code + "&grant_type=authorization_code&scope=read write&redirect_uri=http://218.194.184.150:5901/versioninfo.html");
            myRequest.Method = "POST";
            myRequest.ContentType = "text/xml";
            myRequest.Headers.Add("Authorization: " + " Basic " + user);//添加验证头
            try
            {
                HttpWebResponse HttpWResp = (HttpWebResponse)myRequest.GetResponse();
                Stream myStream = HttpWResp.GetResponseStream();
                StreamReader sr = new StreamReader(myStream, Encoding.UTF8);
                StringBuilder strBuilder = new StringBuilder();
                while (-1 != sr.Peek())
                {
                    strBuilder.Append(sr.ReadLine());
                }
                strResult = strBuilder.ToString();
            }
            catch (Exception exp)
            {
                strResult = "error:" + exp.Message;
                LogHelper.WriteLog(strResult);
            }
        }
        catch (Exception exp)
        {
            strResult = "error:" + exp.Message;
            LogHelper.WriteLog(strResult);
        }

        return strResult;
    }