C#請求url，獲取響應的指令碼

public string ResultOfApi(string url)
        {
            //傳送請求
            HttpWebRequest request = null;
            HttpWebResponse response = null;
            request = (HttpWebRequest)HttpWebRequest.Create(url);
            request.Method = "Get";
            request.ContentType 
 
= "application / x - www - form - urlencoded";
            request.UserAgent = "Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.99 Safari/537.36";
            request.Accept = "text / html,application / xhtml + xml,application / xml; q = 0.9,image / webp,image / apng,*/*;q=0.8
 
";
            request.KeepAlive = true;
            //獲取響應
            response = (HttpWebResponse)request.GetResponse();
            Stream S = response.GetResponseStream();
            StreamReader streamreader = new StreamReader(S);
            string result = streamreader.ReadToEnd();
            
 
return result
        }