网页自动登录，自动填充表单代码

实现自动登录某网站，并且登录完成后跳转到指定的页面。然后进行表单的自动填充表单提交 。类型于小型的发帖机  哈哈 （看官在看下面代码的时候，把记得把下面的链接改下）
   public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            webBrowser1.Navigate("www.tiantianit.com");
        }

        private void webBrowser1_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
        {
            if (webBrowser1.Url.ToString() == "www.tiantianit.com")
            {
                webBrowser1.Document.All["username"].InnerText = "tiantianit.com";
                webBrowser1.Document.All["password"].InnerText = "tiantianit.com";
                //webBrowser1.
                HtmlElement tem = null;
                var tem111 = webBrowser1.Document.GetElementsByTagName("input");
                for (int i = 0; i < tem111.Count; i++)
                {
                    HtmlElement aaaa = tem111[i];
                    if (aaaa.GetAttribute("type") == "button")
                    {
                        tem = aaaa;
                    }
                }

                tem.InvokeMember("click");
                Thread.Sleep(1000);
                webBrowser1.Navigate("www.tiantianit.com");//登陆成功后转到写blog
                this.Show();
                //bool isLogIn = false;
                //if (webBrowser1.Url.ToString() == "www.tiantianit.com")
                //{
                //    System.Windows.Forms.MessageBox.Show("用户名或密码错误!");
                //    return;
                //}
                //else
                //{
                //    //isSetForm = false;
                //    //mylogin.Close();
                //    webBrowser1.Navigate("www.tiantianit.com");
                //    this.Show();
                //}
            }
            if (webBrowser1.Url.ToString() == "www.tiantianit.com")
            {
                webBrowser1.Document.All["txtTitle"].InnerText = "hello 我的第一篇博客";
                webBrowser1.Document.All["editor"].InnerText = "hello 我的第一篇博客";
                //var tem111 = webBrowser1.Document.GetElementsByTagName("body");
                //HtmlElement bbbb = null;
                //for (int i = 0; i < tem111.Count; i++)
                //{
                //    HtmlElement aaaa = tem111[i];
                //    if (aaaa.GetAttribute("class") == "editMode")
                //    {
                //        bbbb = aaaa;
                //    }
                //}
                //bbbb.InnerHtml = "hello 我的第一篇博客";
                webBrowser1.Document.GetElementById("selType").SetAttribute("innerHTML", "转载");
                webBrowser1.Document.GetElementById("txtTag2").InnerText = "asp.net";//标题
                webBrowser1.Document.GetElementById("txtTag").InnerText = "asp.net";//内容
                HtmlElement authortb = webBrowser1.Document.All["radChl2"];
                authortb.SetAttribute("checked", "checked");
                

            }
           
        }
    }