อยากสร้าง asp:textbox จาก codebehind ครับ ลองใช้ response.write แล้วมันไม่ได้

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

public partial class _Default : System.Web.UI.Page 
{

    public int count;
    protected void Page_Load(object sender, EventArgs e)
    {
        count = 0; 
    }
    protected void btnIncrease_Click(object sender, EventArgs e)
    {
        
   Response.Write("Question<%=count%>: <asp:HiddenField ID='Hidden' runat='server' />"); 
   Response.Write("<asp:TextBox ID='TextBox1' runat='server' Height='71px' TextMode='MultiLine'" 
   +"Width='322px' />");
   Response.Write("<br />");
   Response.Write("Answer:");
   Response.Write("<asp:RadioButton ID=RadioButton runat=server GroupName=group<%=count%> />");
   Response.Write("<asp:RadioButton ID=RadioButton runat=server GroupName=group<%=count%> />");
   ++count;
   }
}