NPOI导出数据到Excel
前阵子工作需要，将数据库数据导出到Excel。试了很多方法包括excelpackage（见上一篇）,最后还是感觉NPOI比较好用一些。事实证明NPOI使用很简洁，在.net项目中只需引入一个NPOI.dll文件即可。
（是不是很简洁）
然后就是代码了，这里我导出的是一个标准Excel格式。对于同学们算是一个入门级教程，同学们若想了解更多NPOI 可以自己慢慢研究~ 另外，我这里导出需要提供一个Excel模板，放到指定的目录中。
对于NPOI不支持Excel2007的问题（我本机是Excel2007），我的解决办法是：放了一个Excel2003的Excel模板。
下面附上我的导出方法代码：
1
string tempPath =
"";
2 // 设置Excel模板的存放路径
3 tempPath = Server.MapPath( " ~/xls_files/Template_DeviceIP.xls ");
4 if (tempPath.Length > 0)
5 {
6 string sql = " select ip,ipUser,state,dept from ip_info ";
7 // string sql1 = "select orderId,range,comm_soc_orgname,distinguish,classes,createtime,competent_name,prin_name,phonenumber,numbercount,isParty from st_comm_soc_org order by orderId";
8 // DataTable dtcomm = DbHelperSQL.Query(sql1).Tables[0];
9 DataTable dtsoc = DbHelperSQL.Query(sql).Tables[ 0];
10 if (dtsoc != null && dtsoc.Rows.Count > 0)
11 {
12
13 FileStream file = new FileStream(tempPath, FileMode.Open, FileAccess.Read); // 读入excel模板
14 IWorkbook workbook = new HSSFWorkbook(file);
15 // 设置Excel的样式，这里设置了表格的边框和高度
16 ICellStyle datastyle = workbook.CreateCellStyle();
17 datastyle.Alignment = HorizontalAlignment.Center;
18 datastyle.BorderTop = NPOI.SS.UserModel.BorderStyle.Thin;
19 datastyle.TopBorderColor = HSSFColor.Black.Index;
20 datastyle.BorderRight = NPOI.SS.UserModel.BorderStyle.Thin;
21 datastyle.RightBorderColor = HSSFColor.Black.Index;
22 datastyle.BorderBottom = NPOI.SS.UserModel.BorderStyle.Thin;
23 datastyle.BottomBorderColor = HSSFColor.Black.Index;
24 datastyle.BorderLeft = NPOI.SS.UserModel.BorderStyle.Thin;
25 datastyle.LeftBorderColor = HSSFColor.Black.Index;
26 IFont datafont = workbook.CreateFont();
27 datafont.FontHeightInPoints = 10; // 字号
28 datastyle.SetFont(datafont);
29
30
31 string bakPath = " IP表.xls ";
32 int totalIndex = dtsoc.Rows.Count;
33 int rowIndex = 3; // 起始行
34 int dtRowIndex = dtsoc.Rows.Count; // DataTable的数据行数
35
36 ISheet sheet = workbook.GetSheet( " IP表 ");
37 foreach (DataRow row in dtsoc.Rows)
38 {
39 #region 填充内容
40 // HSSFRow dataRow = sheet.GetRow(rowIndex);
41 IRow dataRow = sheet.CreateRow(rowIndex);
42 int columnIndex = 0; // 开始列（0为标题列，从1开始）
43 foreach (DataColumn column in dtsoc.Columns)
44 {
45 // 列序号赋值
46 if (columnIndex >= dtsoc.Columns.Count)
47 break;
48
49 // HSSFCell newCell = dataRow.GetCell(columnIndex);
50 // if (newCell == null)
51 ICell newCell = dataRow.CreateCell(columnIndex);
52 string drValue = row[column].ToString();
53
54
55 switch (column.DataType.ToString())
56 {
57 case " System.String ": // 字符串类型
58 newCell.SetCellValue(drValue);
59 newCell.CellStyle = datastyle;
60 break;
61 case " System.DateTime ": // 日期类型
62 DateTime dateV;
63 DateTime.TryParse(drValue, out dateV);
64 newCell.SetCellValue(dateV);
65 newCell.CellStyle = datastyle;
66 break;
67 case " System.Boolean ": // 布尔型
68 bool boolV = false;
69 bool.TryParse(drValue, out boolV);
70 newCell.SetCellValue(boolV);
71 newCell.CellStyle = datastyle;
72 break;
73 case " System.Int16 ": // 整型
74 case " System.Int32 ":
75 case " System.Int64 ":
76 case " System.Byte ":
77 int intV = 0;
78 int.TryParse(drValue, out intV);
79 newCell.SetCellValue(intV);
80 newCell.CellStyle = datastyle;
81 break;
82 case " System.Decimal ": // 浮点型
83 case " System.Double ":
84 double doubV = 0;
85 double.TryParse(drValue, out doubV);
86 newCell.SetCellValue(doubV);
87 newCell.CellStyle = datastyle;
88 break;
89 case " System.DBNull ": // 空值处理
90 newCell.SetCellValue( "");
91 newCell.CellStyle = datastyle;
92 break;
93 default:
94 newCell.SetCellValue( "");
95 newCell.CellStyle = datastyle;
96 break;
97 }
98 columnIndex++;
99 }
100 #endregion
101
102 rowIndex++;
103 }
104 using (MemoryStream ms = new MemoryStream())
105 {
106 workbook.Write(ms);
107 ms.Flush();
108 ms.Position = 0;
109 sheet = null;
110 workbook = null;
111
112
113 // sheet.Dispose();
114 // workbook.Dispose(); // 一般只用写这一个就OK了，他会遍历并释放所有资源，但当前版本有问题所以只释放sheet
115 byte[] data = ms.ToArray();
116 // fs.Write(data, 0, data.Length);
117
118 #region 客户端保存
119 HttpResponse response = System.Web.HttpContext.Current.Response;
120 response.Clear();
121 // Encoding pageEncode = Encoding.GetEncoding(PageEncode);
122 response.Charset = " UTF-8 ";
123 response.ContentType = " application/vnd-excel "; // "application/vnd.ms-excel";
124 System.Web.HttpContext.Current.Response.AddHeader( " Content-Disposition ", string.Format( " attachment; filename= " + bakPath));
125 System.Web.HttpContext.Current.Response.BinaryWrite(data);
126 }
127
128 }
129 else
130 {
131 Page.ClientScript.RegisterStartupScript( this.GetType(), " ClientScript ", " alert('无数据导出！'); ", true);
132 return;
133 }
134 }
2 // 设置Excel模板的存放路径
3 tempPath = Server.MapPath( " ~/xls_files/Template_DeviceIP.xls ");
4 if (tempPath.Length > 0)
5 {
6 string sql = " select ip,ipUser,state,dept from ip_info ";
7 // string sql1 = "select orderId,range,comm_soc_orgname,distinguish,classes,createtime,competent_name,prin_name,phonenumber,numbercount,isParty from st_comm_soc_org order by orderId";
8 // DataTable dtcomm = DbHelperSQL.Query(sql1).Tables[0];
9 DataTable dtsoc = DbHelperSQL.Query(sql).Tables[ 0];
10 if (dtsoc != null && dtsoc.Rows.Count > 0)
11 {
12
13 FileStream file = new FileStream(tempPath, FileMode.Open, FileAccess.Read); // 读入excel模板
14 IWorkbook workbook = new HSSFWorkbook(file);
15 // 设置Excel的样式，这里设置了表格的边框和高度
16 ICellStyle datastyle = workbook.CreateCellStyle();
17 datastyle.Alignment = HorizontalAlignment.Center;
18 datastyle.BorderTop = NPOI.SS.UserModel.BorderStyle.Thin;
19 datastyle.TopBorderColor = HSSFColor.Black.Index;
20 datastyle.BorderRight = NPOI.SS.UserModel.BorderStyle.Thin;
21 datastyle.RightBorderColor = HSSFColor.Black.Index;
22 datastyle.BorderBottom = NPOI.SS.UserModel.BorderStyle.Thin;
23 datastyle.BottomBorderColor = HSSFColor.Black.Index;
24 datastyle.BorderLeft = NPOI.SS.UserModel.BorderStyle.Thin;
25 datastyle.LeftBorderColor = HSSFColor.Black.Index;
26 IFont datafont = workbook.CreateFont();
27 datafont.FontHeightInPoints = 10; // 字号
28 datastyle.SetFont(datafont);
29
30
31 string bakPath = " IP表.xls ";
32 int totalIndex = dtsoc.Rows.Count;
33 int rowIndex = 3; // 起始行
34 int dtRowIndex = dtsoc.Rows.Count; // DataTable的数据行数
35
36 ISheet sheet = workbook.GetSheet( " IP表 ");
37 foreach (DataRow row in dtsoc.Rows)
38 {
39 #region 填充内容
40 // HSSFRow dataRow = sheet.GetRow(rowIndex);
41 IRow dataRow = sheet.CreateRow(rowIndex);
42 int columnIndex = 0; // 开始列（0为标题列，从1开始）
43 foreach (DataColumn column in dtsoc.Columns)
44 {
45 // 列序号赋值
46 if (columnIndex >= dtsoc.Columns.Count)
47 break;
48
49 // HSSFCell newCell = dataRow.GetCell(columnIndex);
50 // if (newCell == null)
51 ICell newCell = dataRow.CreateCell(columnIndex);
52 string drValue = row[column].ToString();
53
54
55 switch (column.DataType.ToString())
56 {
57 case " System.String ": // 字符串类型
58 newCell.SetCellValue(drValue);
59 newCell.CellStyle = datastyle;
60 break;
61 case " System.DateTime ": // 日期类型
62 DateTime dateV;
63 DateTime.TryParse(drValue, out dateV);
64 newCell.SetCellValue(dateV);
65 newCell.CellStyle = datastyle;
66 break;
67 case " System.Boolean ": // 布尔型
68 bool boolV = false;
69 bool.TryParse(drValue, out boolV);
70 newCell.SetCellValue(boolV);
71 newCell.CellStyle = datastyle;
72 break;
73 case " System.Int16 ": // 整型
74 case " System.Int32 ":
75 case " System.Int64 ":
76 case " System.Byte ":
77 int intV = 0;
78 int.TryParse(drValue, out intV);
79 newCell.SetCellValue(intV);
80 newCell.CellStyle = datastyle;
81 break;
82 case " System.Decimal ": // 浮点型
83 case " System.Double ":
84 double doubV = 0;
85 double.TryParse(drValue, out doubV);
86 newCell.SetCellValue(doubV);
87 newCell.CellStyle = datastyle;
88 break;
89 case " System.DBNull ": // 空值处理
90 newCell.SetCellValue( "");
91 newCell.CellStyle = datastyle;
92 break;
93 default:
94 newCell.SetCellValue( "");
95 newCell.CellStyle = datastyle;
96 break;
97 }
98 columnIndex++;
99 }
100 #endregion
101
102 rowIndex++;
103 }
104 using (MemoryStream ms = new MemoryStream())
105 {
106 workbook.Write(ms);
107 ms.Flush();
108 ms.Position = 0;
109 sheet = null;
110 workbook = null;
111
112
113 // sheet.Dispose();
114 // workbook.Dispose(); // 一般只用写这一个就OK了，他会遍历并释放所有资源，但当前版本有问题所以只释放sheet
115 byte[] data = ms.ToArray();
116 // fs.Write(data, 0, data.Length);
117
118 #region 客户端保存
119 HttpResponse response = System.Web.HttpContext.Current.Response;
120 response.Clear();
121 // Encoding pageEncode = Encoding.GetEncoding(PageEncode);
122 response.Charset = " UTF-8 ";
123 response.ContentType = " application/vnd-excel "; // "application/vnd.ms-excel";
124 System.Web.HttpContext.Current.Response.AddHeader( " Content-Disposition ", string.Format( " attachment; filename= " + bakPath));
125 System.Web.HttpContext.Current.Response.BinaryWrite(data);
126 }
127
128 }
129 else
130 {
131 Page.ClientScript.RegisterStartupScript( this.GetType(), " ClientScript ", " alert('无数据导出！'); ", true);
132 return;
133 }
134 }
导出成功！而且速度很快