using NPOI.HSSF.UserModel;

using NPOI.SS.UserModel;

using NPOI.XSSF.UserModel;

using System;

using System.Collections.Generic;

using System.Data;

using System.IO;

using System.Linq;

using System.Text;

namespace CMS.Common

{

    public class ExcelHelper : IDisposable

    {

        private string fileName = null; //文件名

        private IWorkbook workbook = null;

        private FileStream fs = null;

        private bool disposed;

        public ExcelHelper(string fileName)

        {

            this.fileName = fileName;

            disposed = false;

        }

        /// <summary>

        /// 将DataTable数据导入到excel中

        /// </summary>

        /// <param name="data">要导入的数据</param>

        /// <param name="isColumnWritten">DataTable的列名是否要导入</param>

        /// <param name="sheetName">要导入的excel的sheet的名称</param>

        /// <returns>导入数据行数(包含列名那一行)</returns>

        public int NPOIDataTableToExcel(DataTable data, string sheetName, bool isColumnWritten)

        {

            int i = ;

            int j = ;

            int count = ;

            ISheet sheet = null;

            fs = new FileStream(fileName, FileMode.OpenOrCreate, FileAccess.ReadWrite);

            if (fileName.IndexOf(".xlsx") > ) // 2007版本

                workbook = new XSSFWorkbook();

            else if (fileName.IndexOf(".xls") > ) // 2003版本

                workbook = new HSSFWorkbook();

            try

            {

                if (workbook != null)

                {

                    sheet = workbook.CreateSheet(sheetName);

                }

                else

                {

                    return -;

                }

                if (isColumnWritten == true) //写入DataTable的列名

                {

                    IRow row = sheet.CreateRow();

                    for (j = ; j < data.Columns.Count; ++j)

                    {

                        row.CreateCell(j).SetCellValue(data.Columns[j].ColumnName);

                    }

                    count = ;

                }

                else

                {

                    count = ;

                }

                for (i = ; i < data.Rows.Count; ++i)

                {

                    IRow row = sheet.CreateRow(count);

                    for (j = ; j < data.Columns.Count; ++j)

                    {

                        row.CreateCell(j).SetCellValue(data.Rows[i][j].ToString());

                    }

                    ++count;

                }

                workbook.Write(fs); //写入到excel

                return count;

            }

            catch (Exception ex)

            {

                Console.WriteLine("Exception: " + ex.Message);

                return -;

            }

        }

        /// <summary>

        /// 将excel中的数据导入到DataTable中

        /// </summary>

        /// <param name="sheetName">excel工作薄sheet的名称</param>

        /// <param name="isFirstRowColumn">第一行是否是DataTable的列名</param>

        /// <returns>返回的DataTable</returns>

        public DataTable NPOIExcelToDataTable(string sheetName, bool isFirstRowColumn)

        {

            ISheet sheet = null;

            DataTable data = new DataTable();

            int startRow = ;

            try

            {

                fs = new FileStream(fileName, FileMode.Open, FileAccess.Read);

                if (fileName.IndexOf(".xlsx") > ) // 2007版本

                {

                    workbook = new XSSFWorkbook(fs);

                }

                else if (fileName.IndexOf(".xls") > ) // 2003版本

                {

                    workbook = new HSSFWorkbook(fs);

                }

                if (sheetName != null)

                {

                    sheet = workbook.GetSheet(sheetName);

                    if (sheet == null) //如果没有找到指定的sheetName对应的sheet，则尝试获取第一个sheet

                    {

                        sheet = workbook.GetSheetAt();

                    }

                }

                else

                {

                    sheet = workbook.GetSheetAt();

                }

                if (sheet != null)

                {

                    IRow firstRow = sheet.GetRow();

                    int cellCount = firstRow.LastCellNum; //一行最后一个cell的编号 即总的列数

                    if (isFirstRowColumn)

                    {

                        for (int i = firstRow.FirstCellNum; i < cellCount; ++i)

                        {

                            ICell cell = firstRow.GetCell(i);

                            if (cell != null)

                            {

                                string cellValue = cell.StringCellValue;

                                if (cellValue != null)

                                {

                                    DataColumn column = new DataColumn(cellValue);

                                    data.Columns.Add(column);

                                }

                            }

                        }

                        startRow = sheet.FirstRowNum + ;

                    }

                    else

                    {

                        startRow = sheet.FirstRowNum;

                    }

                    //startRow = sheet.FirstRowNum + 1;

                    //最后一列的标号

                    int rowCount = sheet.LastRowNum;

                    for (int i = startRow; i <= rowCount; ++i)

                    {

                        IRow row = sheet.GetRow(i);

                        if (row == null) continue; //没有数据的行默认是null　　　　　　　

                        DataRow dataRow = data.NewRow();

                        for (int j = row.FirstCellNum; j < cellCount; ++j)

                        {

                            if (row.GetCell(j) != null) //同理，没有数据的单元格都默认是null

                                dataRow[j] = row.GetCell(j).ToString();

                        }

                        data.Rows.Add(dataRow);

                    }

                }

                return data;

            }

            catch (Exception ex)

            {

                Console.WriteLine("Exception: " + ex.Message);

                return null;

            }

        }

        public void Dispose()

        {

            Dispose(true);

            GC.SuppressFinalize(this);

        }

        protected virtual void Dispose(bool disposing)

        {

            if (!this.disposed)

            {

                if (disposing)

                {

                    if (fs != null)

                        fs.Close();

                }

                fs = null;

                disposed = true;

            }

        }

    }

}

private DataTable dt = new DataTable();

        protected void Button1_Click(object sender, EventArgs e)

        {

            Inidata();

            string path = Server.MapPath("~/ExportData/" + DateTime.Now.ToString("yyyyMMddHHmmss") + ".xlsx");

            int no  = new Common.ExcelHelper(path).NPOIDataTableToExcel(dt, "sheet1", true);

        }

        /// <summary>

        /// 装载数据

        /// </summary>

        private void Inidata()

        {

            dt.TableName = "sheet1";

            dt.Columns.Add("Name", typeof(string));

            dt.Columns.Add("Team", typeof(string));

            DataRow dr = dt.NewRow();

            DataRow dr1 = dt.NewRow();

            dr["Name"] = "科比";

            dr["Team"] = "湖人";

            dt.Rows.Add(dr);

            dr1["Name"] = "詹姆斯";

            dr1["Team"] = "骑士";

            dt.Rows.Add(dr1);

        }

using Abp.Domain.Services;

using Newtonsoft.Json.Linq;

using NPOI.HSSF.UserModel;

using NPOI.SS.UserModel;

using NPOI.XSSF.UserModel;

using System;

using System.IO;

using System.Text;

using System.Web;

namespace Framework.Common

{

    /// <summary>

    /// Excel 导入导出

    /// </summary>

    public class ExcelHelper : DomainService

    {

        /// <summary>

        /// 读取 Excel

        /// 如果遇到整行为空行就停止读取并返回

        /// </summary>

        /// <param name="jsonHeader">

        /// 返回 JSON 结构所需要字段名称，与 Excel 的列头相对应

        /// </param>

        /// <param name="sheetIndex">

        /// 读取 Excel 时从 sheetIndex Sheet 开始读取，最小值为 0

        /// </param>

        /// <param name="startRowIndex">

        /// 读取 Excel 时从 startRowIndex 行开始读取，最小值为 0

        /// </param>

        /// <param name="filePath">

        /// 要读取的 Excel 文件路径

        /// </param>

        /// <returns></returns>

        public JArray ReadExcel(string[] jsonHeader, int sheetIndex, int startRowIndex, string filePath)

        {

            if (sheetIndex < )

                throw new Exception("sheetIndex 超出最小值，最小值为 0.");

            if (startRowIndex < )

                throw new Exception("startRowIndex 超出最小值，最小值为 0.");

            if (!File.Exists(filePath))

                throw new Exception("文件不存，请检查文件路径是否正确");

            JArray array = new JArray();

            XSSFWorkbook workbook = null;

            using (FileStream fs = new FileStream(filePath, FileMode.Open, FileAccess.Read))

            {

                workbook = new XSSFWorkbook(fs);

            }

            var sheet = workbook.GetSheetAt(sheetIndex);

            GetRow(array, jsonHeader, sheet, startRowIndex);

            return array;

        }

        /// <summary>

        /// 读取 Excel

        /// 如果遇到整行为空行就停止读取并返回

        /// </summary>

        /// <param name="jsonHeader">

        /// 返回 JSON 结构所需要字段名称，与 Excel 的列头相对应

        /// </param>

        /// <param name="sheetIndex">

        /// 读取 Excel 时从 sheetIndex Sheet 开始读取，最小值为 0

        /// </param>

        /// <param name="startRowIndex">

        /// 读取 Excel 时从 startRowIndex 行开始读取，最小值为 0

        /// </param>

        /// <param name="fs"></param>

        /// <returns></returns>

        public JArray ReadExcel(string[] jsonHeader, int sheetIndex, int startRowIndex, Stream fs)

        {

            if (sheetIndex < )

                throw new Exception("sheetIndex 超出最小值，最小值为 0.");

            if (startRowIndex < )

                throw new Exception("startRowIndex 超出最小值，最小值为 0.");

            JArray array = new JArray();

            XSSFWorkbook workbook = new XSSFWorkbook(fs);

            var sheet = workbook.GetSheetAt(sheetIndex);

            GetRow(array, jsonHeader, sheet, startRowIndex);

            return array;

        }

        /// <summary>

        /// 将数据导入到 Excel 模版

        /// </summary>

        /// <param name="array">

        /// JArray 结构，需要导入到 Excel 中的数据

        /// </param>

        /// <param name="jsonHeader">

        /// JSON 结构所需要字段名称，与 Excel 的列头相对应

        /// </param>

        /// <param name="sheetIndex">

        /// 读取 Excel 时从 sheetIndex Sheet 开始读取，最小值为 0

        /// </param>

        /// <param name="startRowIndex">

        /// 读取 Excel 时从 startRowIndex 行开始读取，最小值为 0

        /// </param>

        /// <param name="excelTempPath">

        /// Excel 模版路径

        /// </param>

        /// <param name="exportFileName">

        /// Excel 导出时的文件名称

        /// </param>

        /// <param name="context">

        /// HttpContext 对象

        /// </param>

        public void ImportDataToExcel(JArray array, string[] jsonHeader, int sheetIndex, int startRowIndex, string excelTempPath, string exportFileName, HttpContext context)

        {

            if (sheetIndex < )

                throw new Exception("sheetIndex 超出最小值，最小值为 0.");

            if (startRowIndex < )

                throw new Exception("startRowIndex 超出最小值，最小值为 0.");

            if (!File.Exists(excelTempPath))

                throw new Exception("文件不存，请检查文件路径是否正确");

            IWorkbook workbook = null;

            string tempExt = Path.GetExtension(excelTempPath).ToLower();

            using (FileStream fs = File.Open(excelTempPath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))

            {

                if (tempExt == ".xls")

                {

                    workbook = new HSSFWorkbook(fs);

                }

                else

                {

                    workbook = new XSSFWorkbook(fs);

                }

            }

            ISheet sheet = null;

            if (tempExt == ".xls")

            {

                sheet = (HSSFSheet)workbook.GetSheetAt(sheetIndex);

            }

            else

            {

                sheet = (XSSFSheet)workbook.GetSheetAt(sheetIndex);

            }

            IRow row = null;

            ICell cell = null;

            foreach (var item in array)

            {

                row = sheet.CreateRow(startRowIndex);

                for (var h = ; h < jsonHeader.Length; h++)

                {

                    cell = row.CreateCell(h);

                    cell.SetCellValue(item[jsonHeader[h]].Value<string>());

                }

                startRowIndex++;

            }

            context.Response.ContentType = "application/vnd.ms-excel";

            context.Response.AddHeader("Content-Disposition", "attachment;filename=" + DateTime.Now.ToString("yyyyMMddHHmmss") + ".xlsx");

            context.Response.AddHeader("Content-Transfer-Encoding", "binary");

            context.Response.ContentType = "application/octet-stream";

            context.Response.ContentEncoding = Encoding.UTF8;

            using (MemoryStream file = new MemoryStream())

            {

                workbook.Write(file);

                byte[] buff = file.GetBuffer();

                //context.Response.BinaryWrite(file.GetBuffer());//输出到浏览器

                #region 输出文件

                if (File.Exists(exportFileName))

                {

                    File.Delete(exportFileName);

                }

                using (FileStream fs = new FileStream(exportFileName, FileMode.Create))

                {

                    using (BinaryWriter bw = new BinaryWriter(fs))

                    {

                        bw.Write(buff, , buff.Length);

                    }

                }

                #endregion

            }

        }

        private void GetRow(JArray array, string[] jsonHeader, ISheet sheet, int rowIndex)

        {

            JObject json = new JObject();

            var row = sheet.GetRow(rowIndex);

            if (row != null)

            {

                var hasNext = false;

                object val = string.Empty;

                for (var i = ; i < jsonHeader.Length; i++)

                {

                    var cell = row.GetCell(i);

                    if (cell == null)

                    {

                        val = null;

                        json[jsonHeader[i]] = string.Empty;

                    }

                    else

                    {

                        val = GetCellValue(json, jsonHeader[i], cell);

                    }

                    if (!hasNext && val != null)

                    {

                        // 若该行中，任意单元格不是 string.Empty 则将 hasNext 设置为 true 表示可以递归读取下一行

                        hasNext = true;

                    }

                }

                if (hasNext)

                {

                    json["rowIndex"] = row.RowNum + ;

                    array.Add(json);

                    GetRow(array, jsonHeader, sheet, rowIndex + );

                }

                else

                {

                    return;

                }

            }

        }

        private object GetCellValue(JToken json, string head, ICell cell)

        {

            switch (cell.CellType)

            {

                case CellType.Error:

                case CellType.Unknown:

                case CellType.Blank:

                    return null;

                case CellType.Boolean:

                    json[head] = cell.BooleanCellValue;//.ToString();

                    return cell.BooleanCellValue;

                case CellType.Numeric:

                    //对时间格式的处理

                    short format = cell.CellStyle.DataFormat;

                    if (format ==  || format ==  || format ==  || format ==  || format == )

                    {

                        json[head] = cell.DateCellValue;//.ToString("yyyy-mm-dd HH:mm:ss");

                        return cell.DateCellValue;

                    }

                    json[head] = cell.NumericCellValue;

                    return cell.NumericCellValue;//.ToString("N4");

            }

            json[head] = cell.StringCellValue;

            return cell.StringCellValue;//.ToString("N4");

        }

    }

}

string excelTempPath = System.Web.HttpContext.Current.Server.MapPath("~/TemplateFile/ItemTemp.xls");

            string exportFileName = System.Web.HttpContext.Current.Server.MapPath("~/ExportFile/" + DateTime.Now.ToString("yyyyMMddHHmmss") + ".xls");

            string[] jsonHeader = new string[] { "Code", "Name"};

            JArray array = new JArray();

            foreach (var item in items)

            {

                JObject json = new JObject();

                json["Code"] = item.Code;

                json["Name"] = item.Name;

                array.Add(json);

            }

            new ExcelHelp().ImportDataToExcel(array, jsonHeader, , , excelTempPath, exportFileName, System.Web.HttpContext.Current);