C#WinFrom导出Excel

采用的是以DataGridView的形式导出，使用NPOI.dll

1.由于使用的是DataGridView，所以类需要创建在From的Project下，DLL导入NPOI

2.代码如下

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using NPOI.SS.UserModel;        //NPOI
using NPOI.HSSF.Util;           //NPOI
using NPOI.HSSF.UserModel;      //NPOI
using NPOI.XSSF.UserModel;      //NPOI
using System.IO;
namespace ESMT
{
    public class ExportExcel
    {
        /// <summary>
        ///
        /// </summary>
        /// <param name="grdview">数据表</param>
        /// <param name="sheetName">工作簿名字</param>
        /// <param name="FilePath">文件路径</param>
        /// <param name="columnTitle">列头</param>
        public void ExportToExcel(DataGridView grdview, string sheetName, string FilePath, string[] columnTitle)
        {

            //不允许dataGridView显示添加行，负责导出时会报最后一行未实例化错误
            grdview.AllowUserToAddRows = false;
            HSSFWorkbook workbook = new HSSFWorkbook();
            ISheet sheet = workbook.CreateSheet(sheetName);//创建工作簿
            //设置表头
            IRow headerRow = sheet.CreateRow();//创建第一行
            headerRow.HeightInPoints = ;
            headerRow.CreateCell().SetCellValue("出库表单");//单元格赋值
            ICellStyle headStyle = workbook.CreateCellStyle();
            headStyle.Alignment = NPOI.SS.UserModel.HorizontalAlignment.Center;//格式居中
            IFont font = workbook.CreateFont();
            font.Boldweight = ;
            font.FontHeightInPoints = ;
            headStyle.SetFont(font);
            headerRow.GetCell().CellStyle = headStyle;
            sheet.AddMergedRegion(new NPOI.SS.Util.CellRangeAddress(, , , grdview.ColumnCount - ));//单元格合并 最后个参数是合并个数

            IRow headerRow2 = sheet.CreateRow();//创建第二行列头
            ICellStyle headStyle2 = workbook.CreateCellStyle();
            headStyle2.Alignment = NPOI.SS.UserModel.HorizontalAlignment.Center;
            IFont font2 = workbook.CreateFont();
            font2.FontHeightInPoints = ;
            font2.Boldweight = ;
            headStyle2.SetFont(font2);
            for (int l = ; l < grdview.ColumnCount - ; l++) //列头填值
            {
                headerRow2.CreateCell(l).SetCellValue(columnTitle[l]);
                headerRow2.GetCell(l).CellStyle = headStyle2;
            }

            //设置列宽
            for (int l = ; l < grdview.Columns.Count; l++)
            {
                sheet.DefaultColumnWidth = ;
            }

            //填写内容
            for (int i = ; i < grdview.Rows.Count; i++)
            {
                IRow row = sheet.CreateRow(i + );
                for (int j = ; j < grdview.Columns.Count; j++)
                {
                    row.CreateCell(j - , CellType.String).SetCellValue(grdview.Rows[i].Cells[j].Value.ToString());//j-1表示哪个单元格
                }
            }

            using (FileStream stream = File.OpenWrite(FilePath))//创建Excel并写入数据
            {
                workbook.Write(stream);
                stream.Close();
            }
            GC.Collect();
        }
    }
}

ExportExcel

PS：openwtrie 打开或者创建新的文件写入

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using NPOI.SS.UserModel;        //NPOI
using NPOI.HSSF.Util;           //NPOI
using NPOI.HSSF.UserModel;      //NPOI
using NPOI.XSSF.UserModel;      //NPOI
using System.IO;
namespace ESMT
{
    public class ExportExcel
    {
        /// <summary>
        /// ExportToExcel
        /// </summary>
        /// <param name="grdview">数据表</param>
        /// <param name="sheetName">工作簿名字</param>
        /// <param name="FilePath">文件路径</param>
        /// <param name="columnTitle">列头</param>
        public bool ExportToExcel(DataGridView grdview, string sheetName, string FilePath, string[] columnTitle, bool ischeckbox)
        {
            try
            {
                //不允许dataGridView显示添加行，负责导出时会报最后一行未实例化错误
                grdview.AllowUserToAddRows = false;
                HSSFWorkbook workbook = new HSSFWorkbook();
                ISheet sheet = workbook.CreateSheet(sheetName);//创建工作簿

                //设置表头
                IRow headerRow = sheet.CreateRow();//创建第一行
                headerRow.HeightInPoints = ;
                headerRow.CreateCell().SetCellValue("出库表单");//单元格赋值

                ICellStyle headStyle = workbook.CreateCellStyle();//
                headStyle.Alignment = NPOI.SS.UserModel.HorizontalAlignment.Center;//格式居中
                headStyle.VerticalAlignment = NPOI.SS.UserModel.VerticalAlignment.Center;//格式居中

                IFont font = workbook.CreateFont();
                font.Boldweight = ;
                font.FontHeightInPoints = ;
                headStyle.SetFont(font);//设置了第一行样式的字体

                headerRow.GetCell().CellStyle = headStyle;
                sheet.AddMergedRegion(new NPOI.SS.Util.CellRangeAddress(, , , grdview.ColumnCount - ));//单元格合并 最后个参数是合并个数

                IRow headerRow2 = sheet.CreateRow();//创建第二行列头
                ICellStyle headStyle2 = workbook.CreateCellStyle();//设置第二行的样式
                headStyle2.Alignment = NPOI.SS.UserModel.HorizontalAlignment.Center;
                IFont font2 = workbook.CreateFont();
                font2.FontHeightInPoints = ;
                font2.Boldweight = ;
                headStyle2.SetFont(font2);

                ICellStyle headStyle3 = workbook.CreateCellStyle();//内容的样式
                headStyle3.Alignment = NPOI.SS.UserModel.HorizontalAlignment.Center;//格式居中
                headStyle3.VerticalAlignment = NPOI.SS.UserModel.VerticalAlignment.Center;//格式居中

                for (int l = ; l < grdview.ColumnCount - ; l++) //列头填值
                {
                    headerRow2.CreateCell(l).SetCellValue(columnTitle[l]);
                    headerRow2.GetCell(l).CellStyle = headStyle2;
                }
                //设置默认列宽
                //sheet.DefaultColumnWidth = 15;

                //设置列宽
                AutoColumnWidth(sheet, grdview.ColumnCount);

                //填写内容
                for (int i = ; i < grdview.Rows.Count; i++)
                {
                    IRow row = sheet.CreateRow(i + );
                    for (int j = ; j < grdview.Columns.Count; j++)
                    {
                        if (ischeckbox)
                        {//带checkbox的DataGrid
                            row.CreateCell(j - , CellType.String).SetCellValue(grdview.Rows[i].Cells[j].Value.ToString());
                            row.GetCell(j - ).CellStyle = headStyle3;
                        }//j-1表示哪个单元格
                        else
                        {
                            row.CreateCell(j - , CellType.String).SetCellValue(grdview.Rows[i].Cells[j - ].Value.ToString());//j-1表示哪个单元格
                            row.GetCell(j - ).CellStyle = headStyle3;
                        }
                    }
                }

                using (FileStream stream = File.OpenWrite(FilePath))//创建Excel并写入数据
                {
                    workbook.Write(stream);
                    stream.Close();
                }
                GC.Collect();
                return true;//导出成功
            }
            catch (Exception)
            {

                return false;//导出失败
            }
        }
        /// <summary>
        /// 自适应列宽
        /// </summary>
        /// <param name="sheet"></param>
        /// <param name="cols"></param>
        public void AutoColumnWidth(ISheet sheet, int cols)
        {
            for (int col = ; col < cols - ; col++)//个数和列头个数统一
            {
                sheet.AutoSizeColumn(col);//自适应宽度，但是其实还是比实际文本要宽
                int columnWidth = sheet.GetColumnWidth(col) / ;//获取当前列宽度
                for (int rowIndex = ; rowIndex <= sheet.LastRowNum; rowIndex++)
                {
                    IRow row = sheet.GetRow(rowIndex);
                    ICell cell = row.GetCell(col);
                    int contextLength = Encoding.UTF8.GetBytes(cell.ToString()).Length;//获取当前单元格的内容宽度
                    columnWidth = columnWidth < contextLength ? contextLength : columnWidth;

                }
                sheet.SetColumnWidth(col, columnWidth * );//设置列宽

            }
        }
    }

}

改善版1.0

3.From窗口点击导出按钮

 string[] columnTitle = { "序号", "仓位", "Facility", "供应商料号", "料号", "料卷ID", "料卷数量", "储位号", "Date Code/Lot", "生产日期", "供应商编码", "入仓时间" };
            string localFilePath = "";// fileNameExt, newFileName, FilePath;
            SaveFileDialog sfd = new SaveFileDialog();//保存文件窗口
            //设置文件类型
            sfd.Filter = "Excel(97-2003)|*.xls";//保存类型为EXCEL
            //保存对话框是否记忆上次打开的目录
            sfd.RestoreDirectory = true;

            //点了保存按钮进入
            if (sfd.ShowDialog() == DialogResult.OK)
            {
                localFilePath = sfd.FileName.ToString(); //获得文件路径
                ex.ExportToExcel(grdData, "出库表单", localFilePath, columnTitle);
            }

导出按钮

通过以上三步，完成点击导出按钮，后选择保存位置并命名，调用EportExcel方法完成导出Excel。

PS：使用DataTable的操作是一样，只是赋值的时候取DataTable的值。GC 是自动垃圾收集  如果没有Checkbox的时候可以加入一个判断标记为 传参的时候加入，根据标记为来改变赋值情况。