ASP.NET

Dim txt_FirstName_Field As Textbox
txt_FirstName_Field = new TextBox
With txt_FirstName_Field
.ID = "txtFirstName"
.Text = "SomeValue"
End With 
controls.Add( txt_FirstName_Field );

Session["url1"] = url;
            string s = Request.QueryString["page"].ToString();
            if (Request.QueryString["page"].ToString() == null)
            {
                Session["s"] = Convert.ToString(0);
            }
            else
            {
                Session["s"] = Convert.ToString(1);
            }

        }
        if (b == true && Session["s"] == Convert.ToString(1))
        {
            Session["logintrue"] = "logintrue";
            Session["member_name1"] = member_nm;
            Session["member_email1"] = member_eml;
            Session["member_id1"] = member_id;
            string s = Request.QueryString["page"].ToString();
            Response.Redirect(s);
        
        }
        else if (b == true && Session["s"] == Convert.ToString(0))
        {
            Session["logintrue"] = "logintrue";
           Request.QueryString["page"].ToString();
            Response.Redirect("~/member.aspx");

        }
        else
        {
            lbl_error.Text = "Invalid email or password";
        }