NOPI 基本读写

        //获取cell的数据，并设置为对应的数据类型
        public object GetCellValue(ICell cell)
        {
            object value = null;
            try
            {
                if (cell.CellType != CellType.Blank)
                {
                    switch (cell.CellType)
                    {
                        case CellType.Numeric:
                            // Date comes here
                            if (DateUtil.IsCellDateFormatted(cell))
                            {
                                value = cell.DateCellValue;
                            }
                            else
                            {
                                // Numeric type
                                value = cell.NumericCellValue;
                            }
                            break;
                        case CellType.Boolean:
                            // Boolean type
                            value = cell.BooleanCellValue;
                            break;
                        case CellType.Formula:
                            value = cell.CellFormula;
                            break;
                        default:
                            // String type
                            value = cell.StringCellValue;
                            break;
                    }
                }
            }
            catch (Exception)
            {
                value = "";
            }

            return value;
        }
        //npoi读excel方法
        public void ReadFromExcelFile(string filePath)
        {
            IWorkbook wk = null;
            string extension = System.IO.Path.GetExtension(filePath);
            try
            {
                FileStream fs = File.OpenRead(filePath);
                if (extension.Equals(".xls"))
                {
                    //把xls文件中的数据写入wk中
                    wk = new HSSFWorkbook(fs);
                }
                else
                {
                    //把xlsx文件中的数据写入wk中
                    wk = new XSSFWorkbook(fs);
                }

                fs.Close();
                //读取当前表数据
                ISheet sheet = wk.GetSheetAt(0);

                IRow row;
                //LastRowNum 是当前表的总行数-1（注意）
                //LastCellNum 是当前行的总列数

                for (int i = 0; i <= sheet.LastRowNum; i++)
                {
                    row = sheet.GetRow(i);  //读取当前行数据
                    if (row != null && i!=0)
                    {
                        DateTime value1 = DateTime.Parse( row.GetCell(0).ToString());
                        string value2 = row.GetCell(1).ToString();
                        string value3 = row.GetCell(2).ToString();
                        string value4 = row.GetCell(3).ToString();
                        string value5 = row.GetCell(4).ToString();
                        string value6 = row.GetCell(5).ToString();
                        string value7 = row.GetCell(6).ToString();
                        string value8 = row.GetCell(7).ToString();
                        Health.Model.PatientSchedule temp1 = new Health.Model.PatientSchedule();
                        temp1.BeginDate = value1;
                        temp1.BeginTime = value2;
                        temp1.EndTime = value3;
                        temp1.Content = value4;
                        temp1.Center = value5;
                        temp1.DicDept = value6;
                        temp1.Staves = value7;
                        temp1.PlanTips = value8;
                        temp1.ID = 0;
                        temp1.InHosID = Datagrid1_selectedItem.InHosID;
                        temp1.PatientID = Datagrid1_selectedItem.PatID;
                        temp1.RegDatetime = DateTime.Now;
                        temp1.RegUser = Health.Config.UserProfiles.UserName;
                        temp1.State = 1;
                        Datagrid2_ItemsSource.Add(temp1);


                    }
                }
            }

            catch (Exception e)
            {
                //只在Debug模式下才输出
                Console.WriteLine(e.Message);
            }
        }
        //根据数据类型设置不同类型的cell
        public static void SetCellValue(ICell cell, object obj)
        {
            if (obj.GetType() == typeof(int))
            {
                cell.SetCellValue((int)obj);
            }
            else if (obj.GetType() == typeof(double))
            {
                cell.SetCellValue((double)obj);
            }
            else if (obj.GetType() == typeof(IRichTextString))
            {
                cell.SetCellValue((IRichTextString)obj);
            }
            else if (obj.GetType() == typeof(string))
            {
                cell.SetCellValue(obj.ToString());
            }
            else if (obj.GetType() == typeof(DateTime))
            {
                cell.SetCellValue((DateTime)obj);
            }
            else if (obj.GetType() == typeof(bool))
            {
                cell.SetCellValue((bool)obj);
            }
            else
            {
                cell.SetCellValue(obj.ToString());
            }
        }
        //npoi写excel方法
        public void WriteToExcel(string filePath)
        {
            //创建工作薄  
            IWorkbook wb;
            string extension = System.IO.Path.GetExtension(filePath);
            //根据指定的文件格式创建对应的类
            if (extension.Equals(".xls"))
            {
                wb = new HSSFWorkbook();
            }
            else
            {
                wb = new XSSFWorkbook();
            }

            //创建一个表单
            ISheet sheet = wb.CreateSheet("行程");

            //行数和列数
            int rowCount = Datagrid2_ItemsSource.Count();

            IRow row;

            for (int i = 0; i < rowCount+1; i++)
            {
                row = sheet.CreateRow(i);//创建第i行
                var cell1 = row.CreateCell(0);
                var cell2 = row.CreateCell(1);
                var cell3 = row.CreateCell(2);
                var cell4 = row.CreateCell(3);
                var cell5 = row.CreateCell(4);
                var cell6 = row.CreateCell(5);
                var cell7 = row.CreateCell(6);
                var cell8 = row.CreateCell(7);
                if (i==0)
                {
                    SetCellValue(cell1, "日期");
                    SetCellValue(cell2, "开始时间");
                    SetCellValue(cell3, "结束时间");
                    SetCellValue(cell4, "日程内容(流程)");
                    SetCellValue(cell5, "执行中心");
                    SetCellValue(cell6, "执行科室");
                    SetCellValue(cell7, "相关人员");
                    SetCellValue(cell8, "备注"); 
                }
                else
                {
                    SetCellValue(cell1, Datagrid2_ItemsSource[i - 1].BeginDate.ToShortDateString());
                    SetCellValue(cell2, Datagrid2_ItemsSource[i - 1].BeginTime);
                    SetCellValue(cell3, Datagrid2_ItemsSource[i - 1].EndTime);
                    SetCellValue(cell4, Datagrid2_ItemsSource[i - 1].Content);
                    SetCellValue(cell5, Datagrid2_ItemsSource[i - 1].Center);
                    SetCellValue(cell6, Datagrid2_ItemsSource[i - 1].DicDept);
                    SetCellValue(cell7, Datagrid2_ItemsSource[i - 1].Staves);
                    SetCellValue(cell8, Datagrid2_ItemsSource[i - 1].PlanTips);
                }


            }

            try
            {
                FileStream fs = File.OpenWrite(filePath);
                wb.Write(fs);//向打开的这个Excel文件中写入表单并保存。  
                fs.Close();
            }
            catch (Exception e)
            {
                Health.Toolkit.MessageBox.Show("保存失败:"+e.Message);
            }
        }

时期格式设置

ICellStyle style0 = wb.CreateCellStyle();
IDataFormat dataformat = wb.CreateDataFormat();

style0.DataFormat = dataformat.GetFormat("yyyy年MM月dd日 HH:mm");