private void button1_Click(object sender, EventArgs e)
        {
            string url = @"http://t.sina.com.cn/k/" + Class1.ChangeKeywordEncoding(textBox1.Text, "utf-8");
            
            WebClient webclient = new WebClient();
            webBrowser2.Url = new Uri(url);            string webcode = webBrowser2.Document.Body.InnerHtml;
            MessageBox.Show(webcode);