关于ListBox控件的问题

如果我选择了ListBox里面的一项,而旁边用于显示信息的文本框内的内容也做出相应的改变.是不是获取ListBox控件的选定值的Value.而这代码是怎么写的.比如:
private void Page_Load(object sender, System.EventArgs e)
{
// 在此处放置用户代码以初始化页面 
myconnection.ConnectionString="server=(local);database=Teacher;uid=sa;pwd=";
DB.Open();
BindData();
}
private void BindData()
{
string selectstr="select * from TWorker";
SqlDataAdapter da=new SqlDataAdapter(selectstr,myconnection);
DataSet ds=new DataSet();
da.Fill(ds,"TWorker");
//设置组合框帮定
LBX_TName.DataSource =ds;
LBX_TName.DataTextField="TName";
LBX_TName.DataValueField = "TNo"; 
LBX_TName.DataBind();
myconnection.Close();
}
而
string TNo=LBX_TName.SelectedValue.ToString().Trim();
string SelectStr="select * from TWorker where TNo="+TNo;
DataRow DR=DB.GetRecord(SelectStr); 
TB_TName.Text=DR["TName"].ToString();
TB_TNo.Text=DR["TNo"].ToString();
DDL_TSex.SelectedItem.Value=DR["TSex"].ToString();
TB_TMinority.Text=DR["TMinority"].ToString();
TB_TBirthday.Text=DR["TBirthday"].ToString();
TB_TPstatus.Text=DR["TPstatus"].ToString();
TB_TCultur.Text=DR["TCultur"].ToString();
DDL_TMarry.SelectedItem.Value=DR["TMarry"].ToString();
TB_TNplace.Text=DR["TNplace"].ToString();
TB_TIdcard.Text=DR["TIdcard"].ToString();
TB_TOfphone.Text=DR["TOfphone"].ToString();
TB_TPnum.Text=DR["TPnum"].ToString();
TB_TPosition.Text=DR["TPosition"].ToString();
TB_TPtime.Text=DR["TPtime"].ToString();
LB_TName.Text=TB_TName.Text;
要写在什么地方?>???