/// <summary>方法一：比较推荐 
/// 用HttpWebRequest取得网页源码 
/// 对于带BOM的网页很有效，不管是什么编码都能正确识别 
/// </summary> 
/// <param name="url">网页地址" </param> 
/// <returns>返回网页源文件</returns> 
public static string GetHtmlSource2(string url) 
{ 
    //处理内容 
    string html = ""; 
    HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url); 
    request.Accept = "*/*"; //接受任意文件 
    request.UserAgent = "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; .NET CLR 1.1.4322)"; //  
    request.AllowAutoRedirect = true;//是否允许302 
    //request.CookieContainer = new CookieContainer();//cookie容器， 
    request.Referer = url; //当前页面的引用 
    HttpWebResponse response = (HttpWebResponse)request.GetResponse(); 
    Stream stream = response.GetResponseStream(); 
    StreamReader reader = new StreamReader(stream, Encoding.Default); 
    html = reader.ReadToEnd(); 
    stream.Close(); 
    return html; 
}

public static string GetHttpData2(string Url) 
{ 
    string sException = null; 
    string sRslt = null; 
    WebResponse oWebRps = null; 
    WebRequest oWebRqst = WebRequest.Create(Url); 
    oWebRqst.Timeout = 50000; 
    try 
    { 
        oWebRps = oWebRqst.GetResponse(); 
    } 
    catch (WebException e) 
    { 
        sException = e.Message.ToString(); 
    } 
    catch (Exception e) 
    { 
        sException = e.ToString(); 
    } 
    finally 
    { 
        if (oWebRps != null) 
        { 
            StreamReader oStreamRd = new StreamReader(oWebRps.GetResponseStream(), Encoding.GetEncoding("utf-8")); 
            sRslt = oStreamRd.ReadToEnd(); 
            oStreamRd.Close(); 
            oWebRps.Close(); 
        } 
    } 
    return sRslt; 
}