How to use windows control library in C# and use it in asp.net net

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;

namespace WindowsControlLibrary1
{

    public partial class tsControl : UserControl
    {
        public tsControl()
        {
            InitializeComponent();
        }
        public String st;
        [ComVisible(true)]
        public String tstString
        {
            get
            {
                return st;
            }
            set
            {
                st = value;
            }

        }
        private void btnSet_Click(object sender, EventArgs e)
        {
            tstString = txtSetValue.Text;
        }

        private void btnGet_Click(object sender, EventArgs e)
        {
            txtSetValue.Text = "2";
        }

        public void test()
        {

        }


    }
}

<tr>
                    <td>
                        <object classid="http:WindowsControlLibrary1.dll#WindowsControlLibrary1.tsControl"
                            height="250" width="350" id="obj" />
                    </td>
                </tr>

<script language="JavaScript">
      <!--
         function doClick() {

            var val = document.getElementById('obj').tstString;
            alert(val);
         }
      // -->
      </script>