public string getWebContent(string strWebURL)
{
try  
{
string strContent;
WebRequest  request = WebRequest.Create(strWebURL);
request.Timeout=30000;WebResponse response = request.GetResponse();
Stream resStream = response.GetResponseStream();
string strCharset=response.ContentType;StreamReader sr = new StreamReader(resStream,System.Text.Encoding.Default);
strContent = sr.ReadToEnd();
resStream.Close(); 
sr.Close();int s = strContent.IndexOf("<DIV id='Content'>",1);
return s.ToString();
}
catch
{
return s;
}
}以下调用:
richTextBox1.Text=getWebContent("http://news.xinhuanet.com/newscenter/2005-03/22/content_2728142.htm");明明是http://news.xinhuanet.com/newscenter/2005-03/22/content_2728142.htm中有"<DIV id='Content'>"但是它返回的竟是-1,怪吧??