高手来帮帮忙啊,C#操作Excel问题,有源码

private void ExportExcelModel(List<NViewModel> list)
        {
            System.Windows.Forms.FolderBrowserDialog dir = new System.Windows.Forms.FolderBrowserDialog();
            dir.ShowDialog();
            string dirPath = dir.SelectedPath;            if (dirPath != string.Empty)
            {
                //Excel文件路径
                string xlsDir = SysConfig.PublicClass.GetTemplatePath();
                //这里是文件列表,每个文件只包含一个sheet,想把多个类型一样的Excel文件合成一个Excel文件多个sheet
                //mList : 物品档案 物品属性.xls
                //                 物品类别.xls
                //                 物品.xls
                Dictionary<string, List<string>> mList = LoadModelList(list);
                foreach (KeyValuePair<string, List<string>> item in mList)
                {
                    Microsoft.Office.Interop.Excel.Application xlApp = new Microsoft.Office.Interop.Excel.Application();                                       if (xlApp == null)
                    {
                        MessageBox.Show("无法创建Excel对象，可能您的机器未安装Excel");
                        return;
                    }
                    Microsoft.Office.Interop.Excel.Workbook myBook = xlApp.Workbooks.Add(Microsoft.Office.Interop.Excel.XlWBATemplate.xlWBATWorksheet);
                    Microsoft.Office.Interop.Excel.Worksheet sheet = null;
                    Microsoft.Office.Interop.Excel.Application srcXlApp = new Microsoft.Office.Interop.Excel.Application();
                    //获取原有的模板                    
                    foreach (string xlsName in item.Value)
                    {
                        //sheet是往前插入的,排序反着排
                        if (sheet != null)
                        {
                            myBook.Sheets.Add(Type.Missing, Type.Missing, Type.Missing, Type.Missing);
                        }
                        sheet = (Microsoft.Office.Interop.Excel.Worksheet)myBook.Worksheets[1];
                        sheet.Name = xlsName.Replace(".xls", string.Empty);
                        myBook.Save();
                        Microsoft.Office.Interop.Excel.Workbook srcWB = srcXlApp.Workbooks.Open(xlsDir + System.IO.Path.DirectorySeparatorChar + xlsName, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing);
                        //得到WorkSheet对象
                        Microsoft.Office.Interop.Excel.Worksheet srcWS = (Microsoft.Office.Interop.Excel.Worksheet)srcWB.Worksheets[1];                        srcWS.Copy(Type.Missing, myBook.Sheets[1]);程序到这里就出错,异常来自HRESULT:0x800A03EC
                        srcWB.Close(false, Type.Missing, Type.Missing);
                        srcWS = null;
                        srcWB = null;                        
                    }
                    srcXlApp.Quit(); 
                    srcXlApp = null;
                    myBook.SaveAs(dirPath + System.IO.Path.DirectorySeparatorChar + item.Key + ".xls", Microsoft.Office.Interop.Excel.XlFileFormat.xlExcel7, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Microsoft.Office.Interop.Excel.XlSaveAsAccessMode.xlNoChange, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing);
                    myBook.Saved = true;
                    sheet = null;
                    myBook = null;
                    xlApp.Quit(); 
                    xlApp = null;
                }
            }
            
        }