一、引入NPOI程序集
下载地址：http://pan.baidu.com/s/1qWI3Vgo
二、运用NPOI导出成excel文件
1 protected void btnOutExcel_Click(object sender, EventArgs e)
2 {
3 HSSFWorkbook workbook = new HSSFWorkbook();//创建一个工作薄
4 ISheet sheet1 = workbook.CreateSheet("学员信息页");//创建一个sheet页
5 IRow rowHeader = sheet1.CreateRow(0);//创建第一行
6 //设置表头内容
7 rowHeader.CreateCell(0, CellType.STRING).SetCellValue("ID");//创建第一行第一列的单元格，设定里面的值为ID
8 rowHeader.CreateCell(1, CellType.STRING).SetCellValue("姓名");
9 rowHeader.CreateCell(2, CellType.STRING).SetCellValue("用户名");
10 rowHeader.CreateCell(3, CellType.STRING).SetCellValue("手机号");
11 rowHeader.CreateCell(4, CellType.STRING).SetCellValue("班级");
12 rowHeader.CreateCell(5, CellType.STRING).SetCellValue("创建时间");
13 //设置数据内容
14 OpenDB();
15 string strSql = "select UserId,RealName,UserName,PhoneNum,Phase,CreatedTime from UserInfor";
16 using (cmd = new SqlCommand(strSql, con))
17 {
18 using (read = cmd.ExecuteReader())
19 {
20 int i = 0;
21 while (read.Read())
22 {
23 i++;
24 IRow rowData = sheet1.CreateRow(i);
25 rowData.CreateCell(0, CellType.STRING).SetCellValue(read["UserId"].ToString());//创建第一行第一列的单元格，设定里面的值为ID
26 rowData.CreateCell(1, CellType.STRING).SetCellValue(read["RealName"].ToString());
27 rowData.CreateCell(2, CellType.STRING).SetCellValue(read["UserName"].ToString());
28 rowData.CreateCell(3, CellType.STRING).SetCellValue(read["PhoneNum"].ToString());
29 rowData.CreateCell(4, CellType.STRING).SetCellValue(read["Phase"].ToString());
30
31 ICellStyle styledate = workbook.CreateCellStyle();
32 IDataFormat format = workbook.CreateDataFormat();
33 styledate.DataFormat = format.GetFormat("yyyy\"年\"m\"月\"d\"日\"");
34 ICell cellInDate = rowData.CreateCell(5, CellType.NUMERIC);
35 cellInDate.CellStyle = styledate;
36 cellInDate.SetCellValue(read["CreatedTime"].ToString());
37 }
38 using (Stream stream = File.OpenWrite("e:/1.xls"))
39 {
40 workbook.Write(stream);
41 }
42 }
43 }
44 }
三、从excel文件里面导出数据
1 protected void btnFromExcel_Click(object sender, EventArgs e)
2 {
3 StringBuilder sb = new StringBuilder();
4 sb.Append("<table>");
5 sb.Append("<tr><th>ID</th><th>姓名</th><th>用户名</th><th>手机号</th><th>班级</th><th>创建时间</th></tr>");
6 using (Stream stream = File.OpenRead("e:/1.xls"))
7 {
8 HSSFWorkbook workbook = new HSSFWorkbook(stream);
9 int j = workbook.GetSheetAt(0).LastRowNum;
10 for (int row = 1; row <= j; row++)
11 {
12 sb.Append("<tr>");
13 sb.Append(string.Format("<td>{0}</td><td>{1}</td><td>{2}</td><td>{3}</td><td>{4}</td><td>{5}</td>", workbook.GetSheetAt(0).GetRow(row).GetCell(0).StringCellValue, workbook.GetSheetAt(0).GetRow(row).GetCell(1).StringCellValue, workbook.GetSheetAt(0).GetRow(row).GetCell(2).StringCellValue, workbook.GetSheetAt(0).GetRow(row).GetCell(3).StringCellValue, workbook.GetSheetAt(0).GetRow(row).GetCell(4).StringCellValue, workbook.GetSheetAt(0).GetRow(row).GetCell(5).StringCellValue));
14 sb.Append("</tr>");
15 }
16 }
17 sb.Append("<table>");
18 Response.Write(sb.ToString());
19 }
来源：https://www.cnblogs.com/ruanmou001/p/4010866.html