从数据库读出数据到excel完整代码

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 Excel = Microsoft.Office.Interop.Excel;
using System.IO;
using System.Reflection;
using System.Data.Sql;
using System.Data.SqlClient;

namespace ExcleTest
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        DataTable dt;
        private void button1_Click(object sender, EventArgs e)
        {
            string connStr = "Integrated Security=SSPI;Persist Security Info=False;Initial Catalog=RiskAssesment;Data Source=.";
            SqlConnection conn = new SqlConnection(connStr);
            conn.Open(); //打开数据库
            SqlCommand cmd = new SqlCommand();
            cmd.Connection = conn;
            cmd.CommandText = "select * from PipeClass";
            SqlDataAdapter sda = new SqlDataAdapter(cmd.CommandText, conn);
            DataSet ds = new DataSet();
            sda.Fill(ds);
            dataGridView1.DataSource = ds.Tables[0];
             dt = ds.Tables[0];
            conn.Close();
        }

        private void button2_Click(object sender, EventArgs e )
        {
            string s=@"G:\c#\ExcleTest\ExcleTest\XLS\11.xls";
            CreateExcel(dt,s);
        }
        public void CreateExcel(DataTable dt, string fileName)
        {
            System.Diagnostics.Process[] arrProcesses;
            arrProcesses = System.Diagnostics.Process.GetProcessesByName("Excel");
            foreach (System.Diagnostics.Process myProcess in arrProcesses)
            {
                myProcess.Kill();
            }

            Object missing = Missing.Value;
            Microsoft.Office.Interop.Excel.Application m_objExcel =

            new Microsoft.Office.Interop.Excel.Application();
            Microsoft.Office.Interop.Excel.Workbooks m_objWorkBooks = m_objExcel.Workbooks;
            Microsoft.Office.Interop.Excel.Workbook m_objWorkBook = m_objWorkBooks.Add(true);
            Microsoft.Office.Interop.Excel.Sheets m_objWorkSheets = m_objWorkBook.Sheets; ;
            Microsoft.Office.Interop.Excel.Worksheet m_objWorkSheet =

             (Microsoft.Office.Interop.Excel.Worksheet)m_objWorkSheets[1];
            int intFeildCount = dt.Columns.Count;
            for (int col = 0; col < intFeildCount; col++)
            {
                m_objWorkSheet.Cells[1, col + 1] = dt.Columns[col].ToString();
            }
            for (int intRowCount = 0; intRowCount < dt.Rows.Count; intRowCount++)
            {
                for (int intCol = 0; intCol < dt.Columns.Count; intCol++)
                {
                    m_objWorkSheet.Cells[intRowCount + 2, intCol + 1] = "'" + dt.Rows[intRowCount][intCol].ToString();
                }
            }

            if (File.Exists(fileName))
            {
                File.Delete(fileName);
            }
            m_objWorkBook.SaveAs(fileName, missing, missing, missing, missing,

             missing, Microsoft.Office.Interop.Excel.XlSaveAsAccessMode.xlNoChange,
             missing, missing, missing, missing, missing);

            m_objExcel = null;

        }
     }
}