How to add Controls Dynamically and Have Them Persist Through Postback

So the need arises and you need to add controls on demand in my case it is so that a user can add multiple accounts to pay by clicking a button. Here is how to do it.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;

public partial class _Default : System.Web.UI.Page
{
    private const int controlCount = 1;

    protected void Page_Init(object sender, EventArgs e)
    {
        
    }

    protected void Page_Load(object sender, EventArgs e)
    {
        if (Page.IsPostBack)
        {
            foreach (HtmlGenericControl item in MyControlState)
            {
                PlaceHolder1.Controls.Add(item);
            }
        }
    }

    private int _CurrentControlcount
    { 
        get
        {
            int _currentControlcount = object.Equals(Session["_currentControlcount"], null) ? controlCount : (int)Session["_currentControlcount"];
            if (Object.Equals(_currentControlcount, null))
            {
                _currentControlcount = new int();
                _currentControlcount = 0;
                Session["_currentControlcount"] = _currentControlcount;
                
            }
            return _currentControlcount;
        }        
        set
        {
             Session["_currentControlcount"] = value;
        }
    }

    private List<HtmlGenericControl> MyControlState
    {
        get
        {
            List<HtmlGenericControl> myControlState = (List<HtmlGenericControl>)Session["myControlState"];
            if (object.Equals(myControlState,null))
            {
                myControlState = new List<HtmlGenericControl>();
            }

            return myControlState;
        }
        set
        {
            Session["myControlState"] = value;
        }
        
    }

    protected void btnAddControls_Click(object sender, EventArgs e)
    {
        int count = MyControlState.Count();
        HtmlGenericControl myGenericUL = new HtmlGenericControl("ul");
        HtmlGenericControl myGenericLI = new HtmlGenericControl("li");
        TextBox tbx = new TextBox() { Text = string.Format("Textbox{0}", count), ID = string.Format("Textbox{0}", count) };
        myGenericLI.Controls.Add(tbx);
        myGenericUL.Controls.Add(myGenericLI);
        PlaceHolder1.Controls.Add(myGenericUL);
        List<HtmlGenericControl> setup = MyControlState;
        setup.Add(myGenericUL);
        MyControlState = setup;
        _CurrentControlcount = _CurrentControlcount + 1;
    }

}

and the html

<%@ Page Title="Home Page" Language="C#" MasterPageFile="~/Site.master" AutoEventWireup="true"
    CodeFile="Default.aspx.cs" Inherits="_Default" %>
<!-- use the default masterpage from microsoft or whatever you like -->
<asp:Content ID="HeaderContent" runat="server" ContentPlaceHolderID="HeadContent">
</asp:Content>
<asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent">
    <h2>
        Welcome to ASP.NET!
    </h2>
    <p>
        To learn more about ASP.NET visit <a href="http://www.asp.net" title="ASP.NET Website">www.asp.net</a>.
    </p>
    <p>
        You can also find <a href="http://go.microsoft.com/fwlink/?LinkID=152368&amp;clcid=0x409"
            title="MSDN ASP.NET Docs">documentation on ASP.NET at MSDN</a>.
    </p>
    
        <asp:ScriptManager ID="ScriptManager1" runat="server" EnablePageMethods="true"></asp:ScriptManager>
    <asp:PlaceHolder ID="PlaceHolder1" runat="server" >

    </asp:PlaceHolder>
    <br />
    <asp:Button ID="btnAddControls" runat="server" Text="Add Control" 
        onclick="btnAddControls_Click" />

</asp:Content>

now I know that the code is rough and I am touching it up as we speak i really meant to hit draft not publish but it will be ok