foreach (string print in GetHref(html))
        {            //TextBox8.Text = print;
            if (print.Substring(0, 1) == "h") //如果字符串第一个字符不是h则代表不是一个遵守http协议的url
            {
                //Panel prev = new Panel();
                GoogleList.Items.Add(print);
                System.Web.UI.HtmlControls.HtmlContainerControl div = new HtmlGenericControl();
                div.InnerHtml = "<iframe width=120 height=120><A href=\"" + print + "\"target=_blank><img src=\"" + WebPreview(print) + "\"/></iframe>";
                Page.Controls.Add(div);
                UpdatePanel1.Update();
                i++;
                if (i > 2)
                {
                    break;
                }            }        }谢谢大神