使用NPOI导出，读取EXCEL，具有可追加功能
看代码
using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
using System.Data;
using NPOI.SS.UserModel;
using NPOI.XSSF.UserModel;
using NPOI.HSSF.UserModel; namespace NPOIExcel
{
public class ExcelEX
{ /// <summary>
/// 将DataTable数据导入到excel中
/// </summary>
/// <param name="fileName">文件名</param>
/// <param name="data">要导入的数据</param>
/// <param name="sheetName">要导入的excel的sheet的名称</param>
/// <param name="blnAppled">是否是追加模式</param>
/// <param name="isColumnWritten">DataTable的列名是否要导入</param>
/// <returns>导入数据行数(包含列名那一行)</returns>
public static int DataTableToExcel(string fileName, DataTable data, bool blnAppled = false, string sheetName = "sheet1", bool isColumnWritten = true)
{
int i = ;
int j = ;
int count = ;
ISheet sheet = null;
IWorkbook workbook = null;
using (FileStream fs = new FileStream(fileName, FileMode.OpenOrCreate, FileAccess.ReadWrite))
{
if (!blnAppled)
{
if (fileName.IndexOf(".xlsx") > ) // 2007版本
workbook = new XSSFWorkbook();
else if (fileName.IndexOf(".xls") > ) // 2003版本
workbook = new HSSFWorkbook();
}
else
{
if (fileName.IndexOf(".xlsx") > ) // 2007版本
workbook = new XSSFWorkbook(fs);
else if (fileName.IndexOf(".xls") > ) // 2003版本
workbook = new HSSFWorkbook(fs);
} try
{
if (!blnAppled && !string.IsNullOrEmpty(sheetName))
{
if (workbook != null)
{
sheet = workbook.CreateSheet(sheetName);
}
else
{
return -;
}
}
else
{
sheet = workbook.GetSheetAt();
} if (!blnAppled)
{
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 = ;
}
} count = sheet.LastRowNum + ; 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;
} }
catch (Exception ex)
{
Console.WriteLine("Exception: " + ex.Message);
return -;
}
} FileStream outFs = new FileStream(fileName, FileMode.Open);
workbook.Write(outFs);
outFs.Close();
return count;
} /// <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 static DataTable ExcelToDataTable(string fileName, string sheetName = null, bool isFirstRowColumn = true)
{
ISheet sheet = null;
DataTable data = new DataTable();
int startRow = ;
IWorkbook workbook = null;
try
{
FileStream 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;
} //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;
}
} }
}
看测试
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using NPOIExcel; namespace Test
{
class Program
{
static void Main(string[] args)
{
DataTable dt = new DataTable();
dt.Columns.Add("A", typeof(string));
dt.Columns.Add("B", typeof(string));
dt.Columns.Add("C", typeof(string));
for (int i = ; i < ; i++)
{
DataRow dr = dt.NewRow();
for (int j = ; j < ; j++)
{
dr[j] = "1_" + i.ToString() + "_" + j.ToString();
}
dt.Rows.Add(dr);
}
ExcelEX.DataTableToExcel("d:\\123.xlsx",dt);
dt.Rows.Clear(); for (int i = ; i < ; i++)
{
DataRow dr = dt.NewRow();
for (int j = ; j < ; j++)
{
dr[j] = "2_" + i.ToString() + "_" + j.ToString();
}
dt.Rows.Add(dr);
} ExcelEX.DataTableToExcel("d:\\123.xlsx", dt,true);
Console.ReadKey();
}
}
}
看结果