WebClient download HTML source code

using System;
using System.IO;
using System.Net;
using System.Text;

string source;
using (WebClient wc=new WebClient())
{
    //方法1:使用串流讀取
    StreamReader sr=new StreamReader(wc.OpenRead("http://tw.yahoo.com"),Encoding.UTF8);
    source=sr.ReadToEnd();
    sr.Close();
    sr.Dispose();
           
    //方法2:使用webclient.DownloadString()
    //source=wc.DownloadString("http://tw.yahoo.com");
}
Console.WriteLine(source);