跨文档复制excel sheet 页

public class CopyManager
    {
        public static  KeyValuePair<bool,string> CopyWithMessage(string sourcefile, string destfile)
        {
            Microsoft.Office.Interop.Excel.Application application = new Excel.Application();
            Excel.Workbook sourcebook = null;
            Excel.Workbook destinationbook = null;
            try
            {

                application.Visible = false;
                application.DisplayAlerts = false;
                sourcebook = application.Workbooks.Open(sourcefile, false, true, Type.Missing, Type.Missing
                 , Type.Missing, Type.Missing, Type.Missing, Type.Missing
                 , Type.Missing, Type.Missing, Type.Missing, Type.Missing);
                try
                {
                    destinationbook = application.Workbooks.Open(destfile, false, Type.Missing, Type.Missing, Type.Missing
            , Type.Missing, true, Type.Missing, Type.Missing
            , Type.Missing, Type.Missing, Type.Missing, XlCorruptLoad.xlNormalLoad);
                }
                catch (Exception ex)
                {
                    return new KeyValuePair<bool, string>(false, ex.Message);
                }

                int copycount = sourcebook.Worksheets.Count;
                int destsheetcount = destinationbook.Worksheets.Count;
                Excel.Worksheet lastworksheet = destinationbook.Worksheets[destsheetcount];
                Excel.Worksheet firstworksheet = destinationbook.Worksheets[1];
                
                for (int i = 1; i <= copycount; i++)
                {
                    Excel.Worksheet worksheet = sourcebook.Worksheets[i];
                    if (worksheet.Name == "Cover")
                    {
                        worksheet.Copy(firstworksheet, Type.Missing);
                    }
                    if (worksheet.Name == "Disclaimers")
                    {
                        worksheet.Copy(Type.Missing, lastworksheet);
                    }
                }
                destinationbook.CheckCompatibility = false;
                if (Path.GetExtension(destfile) == ".xlsx")
                {
                    destinationbook.Save();
                    return new KeyValuePair<bool, string>(true, destfile);
                }
                else
                {
                    string savefilename = Path.Combine(Path.GetDirectoryName(destfile), Path.GetFileNameWithoutExtension(destfile) + ".xlsx");
                    if (File.Exists(savefilename))
                    {
                        File.Delete(savefilename);
                    }
                    destinationbook.SaveAs(savefilename, XlFileFormat.xlWorkbookDefault, Type.Missing, Type.Missing, Type.Missing, Type.Missing, XlSaveAsAccessMode.xlNoChange, XlSaveConflictResolution.xlLocalSessionChanges, false, Type.Missing, Type.Missing, Type.Missing);
                    return new KeyValuePair<bool, string>(true, savefilename);
                }
                //destinationbook.AutoUpdateSaveChanges = false;
                //destinationbook.Save();
            }
            catch (Exception ex)
            {
                 return new KeyValuePair<bool, string>(false, ex.Message); ;
            }
            finally
            {
                if (sourcebook != null)
                {
                    sourcebook.Close(false, Type.Missing, Type.Missing);
                }
                if (destinationbook != null)
                {
                    destinationbook.Close(true, Type.Missing, Type.Missing);
                }
                application.Quit();
                // 强制回收 Excel 进程
                int geneID = System.GC.GetGeneration(application);
                sourcebook = null;
                destinationbook = null;
                application = null;
                System.GC.Collect(geneID);
                ErrorManager.KillErrorProcessNow();
            }
          
        }
    }