using(FileStream stream=new FileStream("C:\Users\XXXXXX\Desktop\1.xls",FileMode.Open))
           {
               HSSFWorkbook workbook=new HSSFWorkbook(stream);
               HSSWSheet sheet=workbook.GetSheetAt(0);
               HSSFRow row=sheet.GetRow(0);
               HSSFCell cell=row.GetCell(0);
               MessageBox.Show(cell.stringcellvalue);

           }
NPOI技术一般用在03版的office,而之后的07班都是用.xlsx结尾的，都是xaml代码，可以吧某个execel表的格式改为zip,exe就可以看到xaml内容了