VS2010用C#访问SQL数据库，念实现用listbox1控件显示表1的某列，listbox2控件显示表2的某列，代码如下

VS2010用C#访问SQL数据库，想实现用listbox1控件显示表1的某列，listbox2控件显示表2的某列，代码如下
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.SqlClient;
using System.Configuration;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            // TODO: 这行代码将数据加载到表“siplace_kanbanDataSet1.kanbanTable”中。您可以根据需要移动或删除它。
            this.kanbanTableTableAdapter.Fill(this.siplace_kanbanDataSet1.kanbanTable);
            BindListBox1();
            //BindListBox2();
        }

        //设定ListBox控件显示内容
        public void BindListBox1()
        {
            string sql1 = "select lId,dtTime from BOARD";
            string sql2 = "select dtTime from CompBlock";
            listBox1.DataSource = GetData1(sql1).Tables[0];
            listBox1.DisplayMember = "lId";
            listBox2.DataSource = GetData2(sql2).Tables[1];
            listBox2.DisplayMember = "dtTime";
        }

        /*public void BindListBox2()
        {            
            string sql2 = "select dtTime from CompBlock";

            listBox2.DataSource = GetData2(sql2);
            listBox2.DisplayMember = "dtTime";
        }*/

        private DataSet GetData1(string sql)
        {
            DataSet table1 = new DataSet();
            String connectionString =
                    "Data Source=SZNC4924;" + "Initial Catalog=OIS1;User ID=sa;Password=Siplace.1";
            SqlConnection conn = new SqlConnection(connectionString);
            SqlDataAdapter dataAdapter1 = new SqlDataAdapter(sql,conn);
            dataAdapter1.Fill(table1);
            return table1;
        }

        private DataSet GetData2(string sql)
        {
            DataSet table2 = new DataSet();
            String connectionString =
                    "Data Source=SZNC4924;" + "Initial Catalog=OIS1;User ID=sa;Password=Siplace.1";
            SqlConnection conn = new SqlConnection(connectionString);
            SqlDataAdapter dataAdapter2 = new SqlDataAdapter(sql, conn);
            dataAdapter2.Fill(table2);
            return table2;
        }
    }

}
结果listbox1有显示结果，可是listbox2没有  这是什么原因  怎么解决？

[解决办法]
 listBox2.DataSource = GetData2(sql2).Tables[0];