public bool ExportFile(System.Data.DataTable dt)

{

    SaveFileDialog sfd = new SaveFileDialog();

    sfd.Filter = "Excel文件(*.xls)|*.xls|所有文件(*.*)|*.*";

    sfd.Title = "Excel文件导出";

    string fileName = "";

    if (sfd.ShowDialog() == DialogResult.OK)

    {

        fileName = sfd.FileName;

        Excel.Application app = new Excel.Application();

        if (app == null)

        {

            MessageBox.Show("Excel启动失败！");

            return false;

        }

        try

        {

            app.Visible = false;

            Excel.Workbook xlWorkBook = app.Workbooks.Add(Type.Missing);

            Excel.Worksheet xlWorkSheet = (Excel.Worksheet)xlWorkBook.Worksheets.get_Item(1);

            int i;

            for (i = 0; i < dt.Columns.Count; i++)

            {

                xlWorkSheet.Cells[1, i + 1] = dt.Columns[i].ColumnName;

            }

            for (i = 0; i < dt.Rows.Count; i++)

            {

                for (int j = 0; j < dt.Columns.Count; j++)

                {

                    string tt = dt.Rows[i][j].ToString();

                    xlWorkSheet.Cells[i + 2, j + 1] = tt;

                }

            }

            xlWorkBook.SaveAs(fileName, Excel.XlFileFormat.xlWorkbookNormal, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Excel.XlSaveAsAccessMode.xlExclusive, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing);

            xlWorkBook.Close(true, Type.Missing, Type.Missing);

            app.Quit();                   

                   

            xlWorkSheet = null;

            xlWorkBook = null;

            return true;

        }

        catch (System.Exception exc)

        {

            MessageBox.Show("excel运行错误：" + exc.Message);

            return false;

        }

    }

    else

    {

        return false;

    }

}