读取EXCEL的数据到datagridview

这个也写的很简单：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace WindowsApplication1
{
    public partial class Form2 : Form
    {
        public Form2()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            this.openFileDialog1.ShowDialog();
            this.textBox1.Text = this.openFileDialog1.FileName;
        }

        private void button2_Click(object sender, EventArgs e)
        {
           string fileName = "";
           fileName = this.textBox1.Text;
           if (this.textBox1.Text != "")
           {
               try
               {
                   string strCon = " Provider = Microsoft.Jet.OLEDB.4.0 ; Data Source = " + fileName + " ;Extended Properties=Excel 8.0";
                   System.Data.OleDb.OleDbConnection myConn = new System.Data.OleDb.OleDbConnection(strCon);
                   string strCom = " SELECT * FROM [punishCase$] ";
                   System.Data.OleDb.OleDbDataAdapter myCommand = new System.Data.OleDb.OleDbDataAdapter(strCom, myConn);
                   System.Data.DataTable dt = new System.Data.DataTable();
                   myCommand.Fill(dt);
                   this.dataGridView1.DataSource = dt;
                   this.label1.Text = myConn.State.ToString();
               }
               catch
               {
                   MessageBox.Show("请选择案件导入的EXCEL");

               }
             
               
              
           }
           else
           {
               MessageBox.Show("请选择Excel文件");
           }



        }
    }
}