C#中Excel数据导入导出

using DevComponents.DotNetBar;
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;
using System.Windows.Forms;

namespace CSharpExcelHandle
{
    /// 

    /// Excel工具类
    /// 
    public static class ExcelUtils
    {
        /// 

        /// Excel某sheet中内容导入到DataTable中
        /// 区分xsl和xslx分别处理
        /// 
        /// Excel文件路径,含文件全名
        /// 
        public static DataTable ExcelSheetImportToDataTable(string filePath)
        {
            DataTable dt = new DataTable();
            IWorkbook hssfworkbook;
            if (Path.GetExtension(filePath).ToLower() == ".xls".ToLower())
            {//.xls
                #region .xls文件处理:HSSFWorkbook
                try
                {
                    using (FileStream file = new FileStream(filePath, FileMode.Open, FileAccess.Read))
                    {
                        hssfworkbook = new HSSFWorkbook(file);
                    }
                }
                catch (Exception e)
                {
                    throw e;
                }

                //ISheet sheet = hssfworkbook.GetSheet(sheetName);//Excel的名称
                ISheet sheet = hssfworkbook.GetSheetAt(0);

                System.Collections.IEnumerator rows = sheet.GetRowEnumerator();
                HSSFRow headerRow = (HSSFRow)sheet.GetRow(0);

                //第二行最后一个方格的编号 即总的列数
                for (int j = 0; j < (sheet.GetRow(1).LastCellNum); j++)
                {
                    //设置每一列的名字
                    HSSFCell cell = (HSSFCell)headerRow.GetCell(j);
                    dt.Columns.Add(cell.ToString());
                }

                while (rows.MoveNext())
                {
                    IRow row = (HSSFRow)rows.Current;
                    DataRow dr = dt.NewRow();

                    if (row.RowNum == 0) continue;//第一行为标题，不需要导入

                    for (int i = 0; i < row.LastCellNum; i++)
                    {
                        if (i >= dt.Columns.Count)//每条记录的单元格数量不能大于表格栏位数量
                        {
                            break;
                        }

                        ICell cell = row.GetCell(i);

                        if ((i == 0) && (string.IsNullOrEmpty(cell.ToString()) == true))//每行第一个cell为空,break
                        {
                            break;
                        }

                        if (cell == null)
                        {
                            dr[i] = null;
                        }
                        else
                        {
                            dr[i] = cell.ToString();
                        }
                    }

                    dt.Rows.Add(dr);
                }
                #endregion
            }
            else
            {//.xlsx
                #region .xlsx文件处理:XSSFWorkbook
                try
                {
                    using (FileStream file = new FileStream(filePath, FileMode.Open, FileAccess.Read))
                    {
                        hssfworkbook = new XSSFWorkbook(file);
                    }
                }
                catch (Exception e)
                {
                    throw e;
                }

                //ISheet sheet = hssfworkbook.GetSheet(sheetName);//Excel的名称
                ISheet sheet = hssfworkbook.GetSheetAt(0);
                System.Collections.IEnumerator rows = sheet.GetRowEnumerator();
                XSSFRow headerRow = (XSSFRow)sheet.GetRow(1);

                //一行最后一个方格的编号 即总的列数 
                for (int j = 0; j < (sheet.GetRow(1).LastCellNum); j++)
                {
                    //设置每一列的名字
                    XSSFCell cell = (XSSFCell)headerRow.GetCell(j);
                    dt.Columns.Add(cell.ToString());
                }
                while (rows.MoveNext())
                {
                    IRow row = (XSSFRow)rows.Current;
                    DataRow dr = dt.NewRow();

                    if (row.RowNum == 0) continue;//第一行标题，不需要导入

                    for (int i = 0; i < row.LastCellNum; i++)
                    {
                        if (i >= dt.Columns.Count) //每条记录的单元格数量不能大于表格栏位数量
                        {
                            break;
                        }
                        ICell cell = row.GetCell(i);
                        if ((i == 0) && (string.IsNullOrEmpty(cell.ToString()) == true))//每行第一个cell为空,break
                        {
                            break;
                        }
                        if (cell == null)
                        {
                            dr[i] = null;
                        }
                        else
                        {
                            dr[i] = cell.ToString();
                        }
                    }
                    dt.Rows.Add(dr);
                }
                #endregion
            }
            return dt;
        }

        /// 

        /// NPOI导出Excel，不依赖本地是否装有Excel，导出速度快
        /// 
        /// 要导出的dataGridView控件
        /// sheet表名
        ///
        public static void ExportToExcel(DataGridView dataGridView1, string sheetName)
        {
            SaveFileDialog fileDialog = new SaveFileDialog();
            fileDialog.Filter = "Excel(97-2003)|*.xls";
            if (fileDialog.ShowDialog() == System.Windows.Forms.DialogResult.Cancel)
            {
                return;
            }
            //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
            dataGridView1.AllowUserToAddRows = false;
            HSSFWorkbook workbook = new HSSFWorkbook();
            ISheet sheet = workbook.CreateSheet(sheetName);
            IRow rowHead = sheet.CreateRow(0);

            HSSFCellStyle hSSFCellStyle = CreateStyle(workbook, NPOI.SS.UserModel.HorizontalAlignment.Left, VerticalAlignment.Center, short.MaxValue, 10, true);
            //填写表头
            for (int i = 0; i < dataGridView1.Columns.Count; i++)
            {
                rowHead.CreateCell(i, CellType.String).SetCellValue(dataGridView1.Columns[i].HeaderText.ToString());
                //设置Excel单元格样式
                rowHead.GetCell(i).CellStyle = hSSFCellStyle;
            }

            hSSFCellStyle = CreateStyle(workbook, NPOI.SS.UserModel.HorizontalAlignment.Left, VerticalAlignment.Center, short.MinValue, 10, true);

            ProcessFrmMgr.ProcessFrmShow(dataGridView1.Rows.Count);//显示进度条
            //填写内容
            for (int i = 0; i < dataGridView1.Rows.Count; i++)
            {
                ProcessFrmMgr.ProcessFrmAdd();//加载进度条
                IRow row = sheet.CreateRow(i + 1);
                for (int j = 0; j < dataGridView1.Columns.Count; j++)
                {
                    row.CreateCell(j, CellType.String).SetCellValue(dataGridView1.Rows[i].Cells[j].Value.ToString());
                    //设置Excel单元格样式
                    row.GetCell(j).CellStyle = hSSFCellStyle;
                }
            }

            ProcessFrmMgr.ProcessFrmClose();//关闭进度条

            //设置单元格自适应宽度
            for (int j = 0; j < dataGridView1.Columns.Count; j++)
            {
                int columnWidth = sheet.GetColumnWidth(j) / 256;//获取当前列宽度
                for (int rowNum = 0; rowNum <= sheet.LastRowNum; rowNum++)//在这一列上循环行
                {
                    IRow currentRow = sheet.GetRow(rowNum);
                    ICell currentCell = currentRow.GetCell(j);
                    int length = Encoding.UTF8.GetBytes(currentCell.ToString()).Length;//获取当前单元格的内容宽度
                    if (columnWidth < length + 1)
                    {
                        columnWidth = length + 1;
                    }//若当前单元格内容宽度大于列宽，则调整列宽为当前单元格宽度，后面的+1是我人为的将宽度增加一个字符
                }
                sheet.SetColumnWidth(j, columnWidth > 255 ? 30000 : columnWidth * 256);//设置最大长度 不能超过255个字符的宽度
            }

            using (FileStream stream = File.OpenWrite(fileDialog.FileName))
            {
                workbook.Write(stream);
                stream.Close();
            }
            MessageBoxEx.Show("导出数据成功！", "操作提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
            GC.Collect();
        }
        /// 

        /// NPOI导出Excel，不依赖本地是否装有Excel，导出速度快
        /// 
        /// 要导出的DataTable
        /// sheet表名
        ///
        public static void ExportToExcel(DataTable dt, string sheetName)
        {
            SaveFileDialog fileDialog = new SaveFileDialog();
            fileDialog.Filter = "Excel(97-2003)|*.xls";
            if (fileDialog.ShowDialog() == System.Windows.Forms.DialogResult.Cancel)
            {
                return;
            }
            //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
            HSSFWorkbook workbook = new HSSFWorkbook();
            ISheet sheet = workbook.CreateSheet(sheetName);
            IRow rowHead = sheet.CreateRow(0);

            HSSFCellStyle hSSFCellStyle = CreateStyle(workbook, NPOI.SS.UserModel.HorizontalAlignment.Left, VerticalAlignment.Center, short.MaxValue, 10, true);
            //填写表头
            for (int i = 0; i < dt.Columns.Count; i++)
            {
                rowHead.CreateCell(i, CellType.String).SetCellValue(dt.Rows[0].Table.Columns[i].ToString());
                //设置Excel单元格样式
                rowHead.GetCell(i).CellStyle = hSSFCellStyle;
            }

            hSSFCellStyle = CreateStyle(workbook, NPOI.SS.UserModel.HorizontalAlignment.Left, VerticalAlignment.Center, short.MinValue, 10, true);

            ProcessFrmMgr.ProcessFrmShow(dt.Rows.Count);//显示进度条
            //填写内容
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                ProcessFrmMgr.ProcessFrmAdd();//加载进度条
                IRow row = sheet.CreateRow(i + 1);
                for (int j = 0; j < dt.Columns.Count; j++)
                {
                    row.CreateCell(j, CellType.String).SetCellValue(dt.Rows[i][j] == null ? "" : dt.Rows[i][j].ToString());
                    //设置Excel单元格样式
                    row.GetCell(j).CellStyle = hSSFCellStyle;
                }
            }

            ProcessFrmMgr.ProcessFrmClose();//关闭进度条

            //设置单元格自适应宽度
            for (int j = 0; j < dt.Columns.Count; j++)
            {
                int columnWidth = sheet.GetColumnWidth(j) / 256;//获取当前列宽度
                for (int rowNum = 0; rowNum <= sheet.LastRowNum; rowNum++)//在这一列上循环行
                {
                    IRow currentRow = sheet.GetRow(rowNum);
                    ICell currentCell = currentRow.GetCell(j);
                    int length = Encoding.UTF8.GetBytes(currentCell.ToString()).Length;//获取当前单元格的内容宽度
                    if (columnWidth < length + 1)
                    {
                        columnWidth = length + 1;
                    }//若当前单元格内容宽度大于列宽，则调整列宽为当前单元格宽度，后面的+1是我人为的将宽度增加一个字符
                }
                sheet.SetColumnWidth(j, columnWidth > 255 ? 30000 : columnWidth * 256);//设置最大长度 不能超过255个字符的宽度
            }

            using (FileStream stream = File.OpenWrite(fileDialog.FileName))
            {
                workbook.Write(stream);
                stream.Close();
            }
            MessageBoxEx.Show("导出数据成功！", "操作提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
            GC.Collect();
        }

        /// 

        /// 设置样式
        /// 
        /// 
        /// 水平布局方式
        /// 垂直布局方式
        /// 字体加粗 (short.MaxValue）
        /// 字体大小
        /// 是否需要边框 true是
        /// 
        private static HSSFCellStyle CreateStyle(HSSFWorkbook wb, NPOI.SS.UserModel.HorizontalAlignment hAlignment, VerticalAlignment vAlignment, short boldWeight, short fontPonint, bool isBorder)
        {
            HSSFCellStyle cellStyle = (HSSFCellStyle)wb.CreateCellStyle(); //创建列头样式
            cellStyle.Alignment = hAlignment; //水平居中
            cellStyle.VerticalAlignment = vAlignment; //垂直居中
            if (isBorder)
            {
                cellStyle.BorderBottom = NPOI.SS.UserModel.BorderStyle.Thin;
                cellStyle.BorderLeft = NPOI.SS.UserModel.BorderStyle.Thin;
                cellStyle.BorderRight = NPOI.SS.UserModel.BorderStyle.Thin;
                cellStyle.BorderTop = NPOI.SS.UserModel.BorderStyle.Thin;
            }
            HSSFFont cellStyleFont = (HSSFFont)wb.CreateFont(); //创建字体
            cellStyleFont.Boldweight = boldWeight; //字体加粗
            cellStyleFont.FontHeightInPoints = fontPonint; //字体大小
            cellStyle.SetFont(cellStyleFont); //将字体绑定到样式
            return cellStyle;
        }


        /// 

        /// DataTable数据去重复
        /// 
        /// 数据源
        /// 重复的数据
        public static DataTable Distinct(DataTable dt)
        {
            string[] filedName = new string[dt.Columns.Count];
            for (int i = 0; i < dt.Columns.Count; i++)
            {
                filedName[i] = dt.Columns[i].ColumnName;
            }
            DataView dv = dt.DefaultView;
            DataTable DistTable = dv.ToTable("Dist", true, filedName);
            return DistTable;
        }

        /// 

        /// 去空行操作
        /// 
        /// DataTable
        public static void DataTableRemoveEmpty(DataTable dt)
        {
            List removelist = new List();
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                bool IsNull = true;
                for (int j = 0; j < dt.Columns.Count; j++)
                {
                    if (!string.IsNullOrEmpty(dt.Rows[i][j].ToString().Trim()))
                    {
                        IsNull = false;
                    }
                }
                if (IsNull)
                {
                    removelist.Add(dt.Rows[i]);
                }
            }
            for (int i = 0; i < removelist.Count; i++)
            {
                dt.Rows.Remove(removelist[i]);
            }
        }


    }
}