winform內調用API

/// <summary>
    /// 調用API接口類
    /// </summary>
    public static class HttpRequest
    {
        //調用接口返回內容         
        public static string GetFunction(string Url,string Method)
        {
            //string serviceAddress = "http://localhost/WebApi/api/OrderInfo/GetOrderInfo"; //示例接口網址
            string serviceAddress = Url;
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(serviceAddress);
            request.Method = Method;
            request.ContentType = "text/html;charset=UTF-8";
            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            Stream myResponseStream = response.GetResponseStream();
            StreamReader myStreamReader = new StreamReader(myResponseStream, Encoding.UTF8);
            string retString = myStreamReader.ReadToEnd();
            myStreamReader.Close();
            myResponseStream.Close();
            return retString;  
        }
    }