C#取得網頁原始碼

public string getSource(string url,string encoding)
        {
            try
            {
                HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
                HttpWebResponse webresponse = (HttpWebResponse)request.GetResponse();
                StreamReader streamReader = new StreamReader(webresponse.GetResponseStream(),
                Encoding.GetEncoding(encoding)); //可改不同編碼 
                return streamReader.ReadToEnd();
            }
            catch { return null; }
 }