CheckBoxList 的資料繫結及資料擷取

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;        //自己匯入命名空間.
public partial class like : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if(!Page.IsPostBack)    //這句很重要,如果不加,則每次載入時都要執行一次綁定,易遺失資料.
        {
        //建立連結;
        SqlConnection con = DB.createConnection();      //不再用 new
        con.Open();
        SqlCommand cmd = new SqlCommand("select * from [personlike]",con);
        SqlDataReader sdr = cmd.ExecuteReader();

        this.CheckBoxList1.DataTextField = "likeContent";  
        this.CheckBoxList1.DataValueField = "ID";

        this.CheckBoxList1.DataSource = sdr;
        this.CheckBoxList1.DataBind();

        sdr.Close();        //關閉記錄集
        con.Close();        //關閉連結

        }
    }

//單擊按鈕讀取所做的操作(資料),用Response.Write()方法顯示.

    protected void Button1_Click(object sender, EventArgs e)
    {
        for(int i=0;i<=this.CheckBoxList1.Items.Count-1;i++)
        {
            if(this.CheckBoxList1.Items[i].Selected)
            {
                Response.Write(this.CheckBoxList1.Items[i].Value.ToString() +"-"+this.CheckBoxList1.Items[i].Text + "<br>");
            }
        }
    }
}