OpenFileDialog选择文件并获取Excel数据

public static System.Data.DataTable ExcelToDatatalbe(int startRow)//导入
        {
            OpenFileDialog ofd = new OpenFileDialog();
            ofd.Filter = "Excel文件|*.xls;*.xlsx";
            ofd.Title = "选择Excel文件";
            ofd.Multiselect = false;
            if (ofd.ShowDialog() == DialogResult.OK)
            {
                Aspose.Cells.Workbook book = new Aspose.Cells.Workbook();
                book.Open(ofd.FileName);
                Aspose.Cells.Worksheet sheet = book.Worksheets[0];
                Cells cells = sheet.Cells;
                //获取excel中的数据保存到一个datatable中
                System.Data.DataTable dt_Import = cells.ExportDataTableAsString(startRow, 0, cells.MaxDataRow + 1, cells.MaxDataColumn + 1, false);
                // dt_Import.
                return dt_Import;
            }
            else
                return new System.Data.DataTable();
        }

/// 

        /// 从Excel获取数据  NPOI
        /// 
        /// 
        /// 
        public static System.Data.DataTable GetExcelData(int startRow, out string msg)
        {
            #region NPOI方式
            OpenFileDialog ofd = new OpenFileDialog();
            ofd.Filter = "Excel文件|*.xls;*.xlsx";
            ofd.Title = "选择Excel文件";
            ofd.Multiselect = false;
            msg = "";
            if (ofd.ShowDialog() == DialogResult.OK)
            {

                bool hasTitle = true;
                string fileName = ofd.FileName;

                Microsoft.Office.Interop.Excel.Application app = new Microsoft.Office.Interop.Excel.Application();
                Sheets sheets;
                object oMissiong = System.Reflection.Missing.Value;
                Microsoft.Office.Interop.Excel.Workbook workbook = null;
                System.Data.DataTable data = new System.Data.DataTable();

                try
                {
                    if (app == null) return null;
                    workbook = app.Workbooks.Open(fileName, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong,
                        oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong);
                    sheets = workbook.Worksheets;

                    //将数据读入到DataTable中
                    Microsoft.Office.Interop.Excel.Worksheet worksheet = (Microsoft.Office.Interop.Excel.Worksheet)sheets.get_Item(1);//读取第一张表 
                    if (worksheet == null) return null;

                    int iRowCount = worksheet.UsedRange.Rows.Count;
                    int iColCount = worksheet.UsedRange.Columns.Count;
                    //生成列头
                    for (int i = 0; i < iColCount; i++)
                    {
                        var name = "column" + i;
                        if (hasTitle)
                        {
                            var txt = ((Microsoft.Office.Interop.Excel.Range)worksheet.Cells[startRow, i + 1]).Text.ToString();
                            if (!string.IsNullOrEmpty(txt)) name = txt;
                        }
                        while (data.Columns.Contains(name)) name = name + "_1";//重复行名称会报错。
                        data.Columns.Add(new DataColumn(name, typeof(string)));
                    }
                    //生成行数据
                    Microsoft.Office.Interop.Excel.Range range;
                    int rowIdx = hasTitle ? 2 : 1;
                    for (int iRow = rowIdx; iRow <= iRowCount; iRow++)
                    {
                        DataRow dr = data.NewRow();
                        for (int iCol = 1; iCol <= iColCount; iCol++)
                        {
                            range = (Microsoft.Office.Interop.Excel.Range)worksheet.Cells[iRow, iCol];
                            dr[iCol - 1] = (range.Value2 == null) ? "" : range.Text.ToString();
                        }
                        data.Rows.Add(dr);
                    }
                }

                catch (Exception ex)
                {
                    ExceptionUtil.DataCL_HTTP(ex, "", "", FileUtil.GetCurSourceFileName());
                    msg = ex.Message;
                    return null;
                }

                finally
                {
                    workbook.Close(false, oMissiong, oMissiong);
                    System.Runtime.InteropServices.Marshal.ReleaseComObject(workbook);
                    workbook = null;
                    app.Workbooks.Close();
                    app.Quit();
                    System.Runtime.InteropServices.Marshal.ReleaseComObject(app);
                    app = null;
                }
                return data;
            }
            #endregion
            return null;

        }

//选择文件夹
FolderBrowserDialog folderBrowserDialog = new FolderBrowserDialog();
if (folderBrowserDialog.ShowDialog(this) == DialogResult.OK)
{
    string FolderName = folderBrowserDialog.SelectedPath;
}