C#实现下载网页源码及获取http状态码的代码

HttpWebRequest hwr = (HttpWebRequest) WebRequest.Create("http://www.jb200.com");
hwr.AllowAutoRedirect = false; //不允许重定向
hwr.Timeout = 10000; //连接超时时间设置
hwr.Method = "GET"; //协议：GET、HEAD、POST、PUT、DELETE、TRACE 或OPTIONS。
try
{
    HttpWebResponse hwrs = (HttpWebResponse)hwr.GetResponse();
    MessageBox.Show(((int)hwrs.StatusCode).ToString()); //获得http状态码 如:200但是404却捕捉不到
    Stream stream=hwrs.GetResponseStream();
    MessageBox.Show(hwrs.CharacterSet); //获取返回结果的字符编码
    StreamReader sr = new StreamReader(stream,Encoding.GetEncoding(hwrs.CharacterSet)); //注意读取的文字编码格式要和写入文件的文字编码格式相同
    StreamWriter sw = new StreamWriter("c:b.html",false,Encoding.GetEncoding(hwrs.CharacterSet)); //写入文字的编码格式和读取时候的编码格式一样
    sw.Write(sr.ReadToEnd());
    sw.Flush();
    sw.Close();
    sr.Close();
}

catch(Exception ex)
{
    MessageBox.Show(ex.ToString());
}