using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
/// <summary>
/// Summary description for Letter
/// </summary>
namespace Insus.NET
{
public class Letter
{
private string _Name;
public string Name
{
get { return _Name; }
set { _Name = value; }
}
public Letter()
{
}
public Letter(string name)
{
this._Name = name;
}
}
} 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
/// <summary>
/// Summary description for LetterEntity
/// </summary>
namespace Insus.NET
{
public class LetterEntity
{
private List<Letter> _Letter = new List<Letter>();
public void Add(Letter l)
{
this._Letter.Add(l);
}
public IEnumerable<Letter> Letters
{
get {
return this._Letter;
}
}
}
} 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using Insus.NET;
public partial class Default2 : System.Web.UI.Page
{
LetterEntity le = new LetterEntity();
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
Data_Binding();
}
le = TemporaryLetters;
}
private void Data_Binding()
{
this.CheckBoxList1.DataSource = le.Letters;
this.CheckBoxList1.DataTextField = "Name";
this.CheckBoxList1.DataBind();
}
protected void Button1_Click(object sender, EventArgs e)
{
Letter l = new Letter();
if (!string.IsNullOrEmpty(this.TextBox1.Text.Trim()))
l.Name = this.TextBox1.Text.Trim();
le.Add(l);
TemporaryLetters = le;
Data_Binding();
}
public LetterEntity TemporaryLetters
{
get
{
if (Session["LetterEntity"] == null)
return new LetterEntity();
else
return (LetterEntity)Session["LetterEntity"];
}
set
{
Session["LetterEntity"] = value;
}
}
}