C#winform中操作Excel数据，导入导出功能

命名空间

using NPOI.HSSF.UserModel;
using NPOI.SS.UserModel;
using NPOI.XSSF.UserModel;
using System;
using System.Data;
using System.Diagnostics;
using System.IO;
using System.Windows.Forms; 

1.导出Excel文件

 /// 

        /// 导出Excel
        /// 
        /// 
        public static void ExportDataToExcel(DataTable TableName)
        {
            string FileName = DateTime.Now.GetHashCode().ToString();
            SaveFileDialog saveFileDialog = new SaveFileDialog
            {
                //设置文件标题
                Title = "导出Excel文件",
                //设置文件类型
                Filter = "Excel 工作簿(*.xlsx)|*.xlsx|Excel 97-2003 工作簿(*.xls)|*.xls",
                //设置默认文件类型显示顺序
                FilterIndex = 1,
                //是否自动在文件名中添加扩展名
                AddExtension = true,
                //是否记忆上次打开的目录
                RestoreDirectory = true,
                //设置默认文件名
                FileName = FileName
            };
            //按下确定选择的按钮
            if (saveFileDialog.ShowDialog() == DialogResult.OK)
            {
                //获得文件路径
                string localFilePath = saveFileDialog.FileName.ToString();

                //数据初始化
                int TotalCount;     //总行数
                int RowRead = 0;    //已读行数

                TotalCount = TableName.Rows.Count;

                //NPOI
                IWorkbook workbook;
                string FileExt = Path.GetExtension(localFilePath).ToLower();
                if (FileExt == ".xlsx")
                {
                    workbook = new XSSFWorkbook();
                }
                else if (FileExt == ".xls")
                {
                    workbook = new HSSFWorkbook();
                }
                else
                {
                    workbook = null;
                }
                if (workbook == null)
                {
                    return;
                }
                ISheet sheet = string.IsNullOrEmpty(FileName) ? workbook.CreateSheet("Sheet1") : workbook.CreateSheet(FileName);

                //秒钟
                Stopwatch timer = new Stopwatch();
                timer.Start();

                try
                {
                    //读取标题
                    IRow rowHeader = sheet.CreateRow(0);
                    for (int i = 0; i < TableName.Columns.Count; i++)
                    {
                        ICell cell = rowHeader.CreateCell(i);
                        cell.SetCellValue(TableName.Columns[i].ColumnName);
                    }

                    //读取数据
                    for (int i = 0; i < TableName.Rows.Count; i++)
                    {
                        IRow rowData = sheet.CreateRow(i + 1);
                        for (int j = 0; j < TableName.Columns.Count; j++)
                        {
                            ICell cell = rowData.CreateCell(j);
                            cell.SetCellValue(TableName.Rows[i][j].ToString());
                        }
                        //状态栏显示
                        RowRead++;
                        int Percent = (int)(100 * RowRead / TotalCount);
                        System.Windows.Forms.Application.DoEvents();
                    }

                    System.Windows.Forms.Application.DoEvents();

                    //转为字节数组
                    MemoryStream stream = new MemoryStream();
                    workbook.Write(stream);
                    var buf = stream.ToArray();

                    //保存为Excel文件
                    using (FileStream fs = new FileStream(localFilePath, FileMode.Create, FileAccess.Write))
                    {
                        fs.Write(buf, 0, buf.Length);
                        fs.Flush();
                        fs.Close();
                    }
                    System.Windows.Forms.Application.DoEvents();

                    //关闭秒钟
                    timer.Reset();
                    timer.Stop();

                    //成功提示
                    if (MessageBox.Show("导出成功，是否立即打开？", "提示", MessageBoxButtons.YesNo, MessageBoxIcon.Information) == DialogResult.Yes)
                    {
                        System.Diagnostics.Process.Start(localFilePath);
                    }
                }
                catch (Exception ex)
                {
                    MessageBox.Show(ex.Message, "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                }
                finally
                {
                    //关闭秒钟
                    timer.Reset();
                    timer.Stop();
                }
            }
        } 

2.导入Excel文件到datetable

 /// 

        /// 获取Excel到Datatable中
        /// 
        /// Excel路径
        /// 返回DataTable数据
        public static DataTable GetExcel(string filePath)
        {
            IWorkbook iwkX;
            using (FileStream fs = File.Open(filePath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
            {
                iwkX = WorkbookFactory.Create(fs);
                fs.Close();
            }
            //sheet
            DataTable dt = new DataTable();
            for (int h = 0; h < iwkX.NumberOfSheets; h++)
            {
                ISheet sheet = iwkX.GetSheetAt(h);
                var rows = sheet.GetRowEnumerator();
                bool isMove = rows.MoveNext();
                //循环sheet
                if (isMove)
                {
                    var Cols = (IRow)rows.Current;
                    dt.TableName = sheet.SheetName;
                    for (int i = 0; i < Cols.LastCellNum; i++)
                    {
                        string str = Cols.GetCell(i).ToString();
                        dt.Columns.Add(Cols.GetCell(i).ToString());
                    }
                    while (rows.MoveNext())
                    {
                        var row = (IRow)rows.Current;
                        var dr = dt.NewRow();
                        for (int i = 0; i < row.LastCellNum; i++)
                        {
                            var cell = row.GetCell(i);
                            if (cell == null)
                            {
                                dr[i] = "";
                            }
                            else
                            {
                                string strdr = cell.ToString();
                                dr[i] = cell.ToString();
                            }
                        }
                        dt.Rows.Add(dr);
                    }
                }
            }
            return dt;
        }