Updates an AD FS 2.0 Login page (FormsSignin.aspx) to autopopulate the user name and set the password focus. * http://mikepfeiffer.net/2012/05/useful-cutomizations-to-ad-fs-2-0-when-deploying-sso-with-office-365/ * https://msdn.microsoft.com/en-us/library/ee895357.aspx

FormsSignIn.aspx.cs

protected void Page_Load( object sender, EventArgs e )
{
	if (!this.IsPostBack)
	{
		// Extract the username fromt he query string and set the username TextBox
		string url = Context.Request.Url.AbsoluteUri;
		System.Collections.Specialized.NameValueCollection parameters = System.Web.HttpUtilitiy.ParseQueryString(url);
		string userName = parameters["username"];

		if (!String.IsNullOrEmpty(userName))
		{
			UsernameTextBox.Text = userName;
			PasswordTextBox.Focus();
		}
	}
}