dropdownlist

我想问一下！！我做了个修改的页面。想把在数据中的数据放在dropdownlist中。然后要修改这个时，让dropdownlist在重新绑定数据库中的某个列改怎么做
--------------------编程问答-------------------- 坦白说我没看懂~~~~~~~~~~~~~ --------------------编程问答-------------------- 没明白. --------------------编程问答-------------------- DropDownList.DataSource=DataSet1;//这个DataSet1就是你从数据库取出来的数据集
DropDownList.DataTextField="数据库中字段1";
DropDownList.DataValueField="这个一般是ID之类的字段，不写的话默认和TextField相同";
DropDownList.DataBind();
如果想改变他绑定的数据源，只需改变DataSource及他的DataTextField等就行了。
--------------------编程问答-------------------- 坦白说，1楼很直接。2楼很坦白，3楼也一样~ --------------------编程问答-------------------- 不明白LZ要表达的意思 --------------------编程问答-------------------- using System;
using System.Data;
using System.Data.SqlClient;
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;

public partial class Default11 : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (Session["NAME"].ToString() == null || Session["NAME"].ToString() == "")
        {
            Response.Redirect("../ErrorPage.aspx?ErrorUrl=AddRKD.aspx&ErrorMsg=请登录");
        }
        else
        {
            if (!IsPostBack)
            {
                this.DPbangding();
                this.getvale();
            }
        }
    }
    private void getvale()
    {
        string sql = "select * from RKD where ID=" + Session["ID1"];
        SqlDataReader dr = config.read(sql);
        if (dr.Read())
        {
            this.TextBox1.Text = dr["PJID"].ToString();
            this.TextBox2.Text = dr["GFNAME"].ToString();
            this.TextBox3.Text = dr["HWNAME"].ToString();
            //this.DropDownList1.SelectedValue = dr["LB"].ToString();
            this.DropDownList1.SelectedIndex = this.DropDownList1.Items.IndexOf(this.DropDownList1.Items.FindByValue(dr["LB"].ToString()));
            this.TextBox4.Text = dr["GG"].ToString();
            this.TextBox5.Text = dr["SL"].ToString();
            this.TextBox6.Text = dr["DJ"].ToString();
            this.TextBox7.Text = dr["ZJ"].ToString();
            this.DropDownList2.SelectedValue = dr["FF"].ToString();
            this.TextBox12.Text = dr["KFH"].ToString();
            this.TextBox13.Text = dr["ZHH"].ToString();
            this.TextBox9.Text=dr["SHR"].ToString();
            this.TextBox11.Text = dr["JSR"].ToString();
            this.TextBox10.Text = dr["BZH"].ToString();
        }
    }
    protected void Button2_Click(object sender, EventArgs e)
    {
        Response.Redirect("DGRKD.aspx");
    }
    protected void Button1_Click(object sender, EventArgs e)
    {
        string sql = "update RKD set PJID='" + this.TextBox1.Text.ToString().Trim() + "',GFNAME='" + this.TextBox2.Text.ToString().Trim() + "',HWNAME='" + this.TextBox3.Text.ToString().Trim() + "',LB='" + this.DropDownList1.SelectedValue.ToString() + "',GG='" + this.TextBox4.Text.ToString().Trim() + "',SL='" + this.TextBox5.Text.ToString().Trim() + "',DJ='" + this.TextBox6.Text.ToString().Trim() + "',ZJ='" + this.TextBox7.Text.ToString().Trim() + "',FF='" + this.DropDownList2.SelectedValue.ToString() + "',KFH='" + this.TextBox12.Text.ToString().Trim() + "',ZHH='" + this.TextBox13.Text.ToString().Trim() + "',SHR='" + this.TextBox9.Text.ToString().Trim() + "',JSR='"+this.TextBox11.Text.ToString().Trim()+"',BZH='"+this.TextBox10.Text.ToString().Trim()+"' where ID="+Session["ID1"];
        int i = config.execsql(sql);
        if (i == 1)
        {
            Response.Write("<script language=javascript>alert('更新成功');</script>");
        }
        else
        {
            Response.Write("<script language=javascript>alert('更新失败')</script>");
        }
    }
    private void DPbangding()
    {
        string sql = "select * from SYSL";
        DataSet ds = config.getgrid(sql);
        this.DropDownList1.DataSource = ds.Tables[0].DefaultView;
        this.DropDownList1.DataValueField = "LB";
        this.DropDownList1.DataBind();
    }
}
--------------------编程问答-------------------- 这是我的代码看看写的哪里有错误
--------------------编程问答-------------------- 眼睛有问题看不出来，自己调示，看哪里出错了就哪里有问题了！ --------------------编程问答-------------------- 一、未关闭数据库
private   void   getvale()方法里，你用了
                SqlDataReader   dr   =   config.read(sql);
                if   (dr.Read())
但，函数结束前，你未关闭数据库
结束前请关闭数据库

只看出这一点

补充：.NET技术 ,  ASP.NET