string excelpath = @"D:\xxx\xxx.xls";
            Microsoft.Office.Interop.Excel.Application app = new Microsoft.Office.Interop.Excel.Application();
            //app.Visible = true;
            object missing = Type.Missing;

            Microsoft.Office.Interop.Excel.Workbook workBook = app.Workbooks.Open(excelpath, missing, missing, missing, missing, missing, missing, missing, missing, missing, missing, missing, missing);
            try
            {
                if (workBook != null)
                {
                    for (int i = 1; i < workBook.Sheets.Count; i++)
                    {
                        Microsoft.Office.Interop.Excel.Worksheet _wSheets = (Microsoft.Office.Interop.Excel.Worksheet)workBook.Worksheets[i];
                        Microsoft.Office.Interop.Excel.Workbook newBook = app.Workbooks.Add(missing);
                        Worksheet mySheet = newBook.Sheets[1] as Worksheet;
                        try
                        {
                            string filename = @"D:\temp\" + _wSheets.Name + ".xls";
                            if (File.Exists(filename))
                            {
                                File.Delete(filename);
                            }
                            //mySheet.Name = _wSheets.Name;
                            _wSheets.Copy(mySheet, missing);
                            newBook.SaveAs(filename, missing
                                , missing, missing, missing, missing, Microsoft.Office.Interop.Excel.XlSaveAsAccessMode.xlShared, missing
                                , missing, missing, missing, missing);
                        }
                        catch (Exception ex)
                        {

                        }
                        finally
                        {
                            _wSheets = null;
                            mySheet = null;
                            newBook.Close();
                        }
                    }
                }
            }
            catch (Exception ex)
            {

            }
            finally
            {
                //newBook.Close();
                workBook.Close();
                app.Quit();
                app = null;
            }