C#下载网页源码的方法，用到msxml2

using System.Text.RegularExpressions;

using MSXML2;

private string gethtm(string link)//------------------------------------下载网页源码

        {

            MSXML2.XMLHTTP xmlhttp = new MSXML2.XMLHTTP();

            Thread.Sleep(5);

            xmlhttp.open("GET", link, false, null, null);

            Thread.Sleep(5);

            xmlhttp.send("");

            Thread.Sleep(5);

            Byte[] b = (Byte[])xmlhttp.responseBody;            

            string str_txt_htm = Encoding.GetEncoding("GB2312").GetString(b).Trim();

            //txtbox.Text = str_txt_htm;

            //Thread.Sleep(5);//暂停线程

            xmlhttp = null;

            b = null;           

            Regex str_re_htm = new Regex(@"<\s*body(.|\n)*", RegexOptions.IgnoreCase);

            Thread.Sleep(5);//暂停线程

            MatchCollection str_re_txt_htm = str_re_htm.Matches(str_txt_htm);

            str_txt_htm = str_re_txt_htm[0].ToString();           

            Thread.Sleep(5);//暂停线程

            str_re_htm = new Regex(@"(<[.|\n]*?script(.|\n)*?/[.|\n]*?script[\n]*>)|(\n)", RegexOptions.IgnoreCase);

            Thread.Sleep(5);//暂停线程

            str_txt_htm = str_re_htm.Replace(str_txt_htm, ""); 

            str_txt_htm = str_txt_htm.Replace("\\", "/");

            //File.Delete(@"C:\Documents and Settings\zjc\Local Settings\Temporary Internet Files\" + Path.GetFileNameWithoutExtension(link)+"[1].htm");

            //Directory.

            str_re_htm = null;

            link = null;

            return str_txt_htm;          

        }