New Post: Transfer My Credential from winform to Yahoo Login page inside the Mozilla Firefox Browser

Hi,
I want to transfer my winform control data (such TextBox, radio button, check box, drop down also button click event as wel) to Firefox, chrome browser. After lot of more search on Google I observe that Html Agility Pack will solve my problem.
But while using this pack I am not able to set the attribute to control that are available in FireFox and Chrome browser.
For this I am try this code

Process objProcess = System.Diagnostics.Process.Start("firefox.exe","https://login.yahoo.com/config/login_verify2?&.src=ym&.intl=us");

        using (var wc = new WebClient())
        {
            var page = wc.DownloadString(objProcess.StartInfo.Arguments);
            HtmlAgilityPack.HtmlDocument doc = new HtmlAgilityPack.HtmlDocument();
            doc.LoadHtml(page);
            HtmlAgilityPack.HtmlNodeCollection nodes = doc.DocumentNode.SelectNodes("//input");
            if (nodes != null)
            {

                for (int i = 0; i < nodes.Count; i++)
                {
                    if (nodes[i].Id == "username")
                    {
                       // MessageBox.Show(nodes[i].Id);

                        nodes[i].SetAttributeValue("username", "Uname");
                    }

                    if (nodes[i].Id == "passwd")
                    {
                       // MessageBox.Show(nodes[i].Id);
                        nodes[i].SetAttributeValue("passwd", "Password");

                    }
                    if (nodes[i].Id == ".save")
                    {
                       // MessageBox.Show(nodes[i].Id);
                        nodes[i].SetAttributeValue(".save", "click");
                    }

                }         
                this.Close();
            }
        }

I just want to transfer this Credential to My Mozilla Firefox browser to my Yahoo Login page from winform.
If My winform Contains Two Text box and 1 button when I click on button the that Text box values are transfer Yahoo Login page inside the FireFox or Chrome browser