Asp.net程序中用NPOI生成标准Excel报表，导入导出一应俱全
上班第一份工作就是做程序数据的导入导出，听起来似乎挺Easy的，开始我也这样认为，但是在实际操作中却不同了...
以往的导出数据是用HTML标签拼接成Table，然后在一行一列的显示成Excel，其实不然，这种Excel是HTML版本的Excel，并不是标准的Excel，所以如果我们把刚导出的数据进行修改保存然后接着导入来更新数据库中的数据就no、no、no了，程序不识别这种格式，那怎么办呢，所以我找到了第三方控件NPOI，来分享一下....
首先我们回顾一下以往用导出HTML格式的Excel文件（如果不存在导入，这种方法完全可以，用NPOI就有点浪费）
代码
1
//
普通形式的下载Excel（HTML格式的Excel）
2
3
//
dt当然是你一些的要导出的数据返回一个DataTable
4
//
fileName是自己定义的文件导出的名字
5
protected
void
CreateExcel(DataTable dt,
string
fileName)
6
{
7
StringBuilder strb
=
new
StringBuilder();
8
strb.Append(
"
<table align=\
"
center\
"
border='1px' style='border-collapse:collapse;table-layout:fixed;font-size:12px'> <tr>
"
);
9
10
//
写列标题
11
int
columncount
=
dt.Columns.Count;
12
for
(
int
columi
=
0
; columi
<
columncount; columi
++
)
13
{
14
strb.Append(
"
<td> <b>
"
+
dt.Columns[columi]
+
"
</b> </td>
"
);
15
}
16
strb.Append(
"
</tr>
"
);
17
//
写数据
18
for
(
int
i
=
0
; i
<
dt.Rows.Count; i
++
)
19
{
20
strb.Append(
"
<tr>
"
);
21
for
(
int
j
=
0
; j
<
dt.Columns.Count; j
++
)
22
{
23
strb.Append(
"
<td>
"
+
dt.Rows[i][j].ToString()
+
"
</td>
"
);
24
}
25
strb.Append(
"
</tr>
"
); }
26
strb.Append(
"
</table>
"
);
27
28
29
Response.Clear();
30
Response.Buffer
=
true
;
31
Response.Charset
=
"
GB2312
"
;
32
Response.AppendHeader(
"
Content-Disposition
"
,
"
attachment;filename=
"
+
FileName
+
"
.xls
"
);
33
Response.ContentEncoding
=
System.Text.Encoding.GetEncoding(
"
GB2312
"
);
//
设置输出流为简体中文
34
Response.ContentType
=
"
application/vnd.xls
"
;
//
设置输出文件类型为excel文件。
35
this
.EnableViewState
=
false
;
36
Response.Write(strb);
37
Response.End();
38
}
39
40
这样可以导出成Excel样式的文件，但它的扩张名并不是.xls,而是.xls.html,所以在导入的时候就做限制了。
如下代码，可以解决此类问题：
一、下载NPOI：http://down.gougou.com/down?cid=DAEA322D9D7F934B898077FB01C3A8CB02A746E6
二、项目添加引用；
三、首先把如下代码封装成一个ExcelHelper类；
四、调用方法。
1、导出：分为DataSet多表导出，DataTable单表导出
首先解析一下由DataSet导出Excel
代码
using
System;
using
System.Data;
using
System.IO;
using
System.Web;
using
NPOI;
using
NPOI.HPSF;
using
NPOI.HSSF;
using
NPOI.HSSF.UserModel;
using
NPOI.POIFS;
using
NPOI.Util;
using
System.Text;
public
class
ExcelHelper
{
///
<summary>
///
由DataSet导出Excel
///
</summary>
///
<param name="sourceTable">
要导出数据的DataTable
</param>
///
<param name="sheetName">
工作表名称
</param>
///
<returns>
Excel工作表
</returns>
private
static
Stream ExportDataSetToExcel(DataSet sourceDs,
string
sheetName)
{
HSSFWorkbook workbook
=
new
HSSFWorkbook();
MemoryStream ms
=
new
MemoryStream();
string
[] sheetNames
=
sheetName.Split(
'
,
'
);
for
(
int
i
=
0
;i
<
sheetNames.Length; i
++
)
{
HSSFSheet sheet
=
workbook.CreateSheet(sheetNames[i]);
HSSFRow headerRow
=
sheet.CreateRow(
0
);
//
handling header.
foreach
(DataColumn column
in
sourceDs.Tables[i].Columns)
headerRow.CreateCell(column.Ordinal).SetCellValue(column.ColumnName);
//
handling value.
int
rowIndex
=
1
;
foreach
(DataRow row
in
sourceDs.Tables[i].Rows)
{
HSSFRow dataRow
=
sheet.CreateRow(rowIndex);
foreach
(DataColumn column
in
sourceDs.Tables[i].Columns)
{
dataRow.CreateCell(column.Ordinal).SetCellValue(row[column].ToString());
}
rowIndex
++
;
}
}
workbook.Write(ms);
ms.Flush();
ms.Position
=
0
;
workbook
=
null
;
return
ms;
}
///
<summary>
///
由DataSet导出Excel
///
</summary>
///
<param name="sourceTable">
要导出数据的DataTable
</param>
///
<param name="fileName">
指定Excel工作表名称
</param>
///
<returns>
Excel工作表
</returns>
public
static
void
ExportDataSetToExcel(DataSet sourceDs,
string
fileName,
string
sheetName)
{
MemoryStream ms
=
ExportDataSetToExcel(sourceDs, sheetName)
as
MemoryStream;
HttpContext.Current.Response.AppendHeader(
"
Content-Disposition
"
,
"
attachment;filename=
"
+
fileName);
HttpContext.Current.Response.BinaryWrite(ms.ToArray());
HttpContext.Current.Response.End();
ms.Close();
ms
=
null
;
}
由DataTable导出Excel
代码
///
<summary>
///
由DataTable导出Excel
///
</summary>
///
<param name="sourceTable">
要导出数据的DataTable
</param>
///
<returns>
Excel工作表
</returns>
private
static
Stream ExportDataTableToExcel(DataTable sourceTable,
string
sheetName)
{
HSSFWorkbook workbook
=
new
HSSFWorkbook();
MemoryStream ms
=
new
MemoryStream();
HSSFSheet sheet
=
workbook.CreateSheet(sheetName);
HSSFRow headerRow
=
sheet.CreateRow(
0
);
//
handling header.
foreach
(DataColumn column
in
sourceTable.Columns)
headerRow.CreateCell(column.Ordinal).SetCellValue(column.ColumnName);
//
handling value.
int
rowIndex
=
1
;
foreach
(DataRow row
in
sourceTable.Rows)
{
HSSFRow dataRow
=
sheet.CreateRow(rowIndex);
foreach
(DataColumn column
in
sourceTable.Columns)
{
dataRow.CreateCell(column.Ordinal).SetCellValue(row[column].ToString());
}
rowIndex
++
;
}
workbook.Write(ms);
ms.Flush();
ms.Position
=
0
;
sheet
=
null
;
headerRow
=
null
;
workbook
=
null
;
return
ms;
}
///
<summary>
///
由DataTable导出Excel
///
</summary>
///
<param name="sourceTable">
要导出数据的DataTable
</param>
///
<param name="fileName">
指定Excel工作表名称
</param>
///
<returns>
Excel工作表
</returns>
public
static
void
ExportDataTableToExcel(DataTable sourceTable,
string
fileName,
string
sheetName)
{
MemoryStream ms
=
ExportDataTableToExcel(sourceTable, sheetName)
as
MemoryStream;
HttpContext.Current.Response.AppendHeader(
"
Content-Disposition
"
,
"
attachment;filename=
"
+
fileName);
HttpContext.Current.Response.BinaryWrite(ms.ToArray());
HttpContext.Current.Response.End();
ms.Close();
ms
=
null
;
}
2、导入
由Excel导入DataTable
代码
///
<summary>
///
由Excel导入DataTable
///
</summary>
///
<param name="excelFileStream">
Excel文件流
</param>
///
<param name="sheetName">
Excel工作表名称
</param>
///
<param name="headerRowIndex">
Excel表头行索引
</param>
///
<returns>
DataTable
</returns>
public
static
DataTable ImportDataTableFromExcel(Stream excelFileStream,
string
sheetName,
int
headerRowIndex)
{
HSSFWorkbook workbook
=
new
HSSFWorkbook(excelFileStream);
HSSFSheet sheet
=
workbook.GetSheet(sheetName);
DataTable table
=
new
DataTable();
HSSFRow headerRow
=
sheet.GetRow(headerRowIndex);
int
cellCount
=
headerRow.LastCellNum;
for
(
int
i
=
headerRow.FirstCellNum; i
<
cellCount; i
++
)
{
DataColumn column
=
new
DataColumn(headerRow.GetCell(i).StringCellValue);
table.Columns.Add(column);
}
for
(
int
i
=
(sheet.FirstRowNum
+
1
); i
<=
sheet.LastRowNum; i
++
)
{
HSSFRow row
=
sheet.GetRow(i);
DataRow dataRow
=
table.NewRow();
for
(
int
j
=
row.FirstCellNum; j
<
cellCount; j
++
)
dataRow[j]
=
row.GetCell(j).ToString();
}
excelFileStream.Close();
workbook
=
null
;
sheet
=
null
;
return
table;
}
///
<summary>
///
由Excel导入DataTable
///
</summary>
///
<param name="excelFilePath">
Excel文件路径，为物理路径。
</param>
///
<param name="sheetName">
Excel工作表名称
</param>
///
<param name="headerRowIndex">
Excel表头行索引
</param>
///
<returns>
DataTable
</returns>
public
static
DataTable ImportDataTableFromExcel(
string
excelFilePath,
string
sheetName,
int
headerRowIndex)
{
using
(FileStream stream
=
System.IO.File.OpenRead(excelFilePath))
{
return
ImportDataTableFromExcel(stream, sheetName, headerRowIndex);
}
}
///
<summary>
///
由Excel导入DataTable
///
</summary>
///
<param name="excelFileStream">
Excel文件流
</param>
///
<param name="sheetName">
Excel工作表索引
</param>
///
<param name="headerRowIndex">
Excel表头行索引
</param>
///
<returns>
DataTable
</returns>
public
static
DataTable ImportDataTableFromExcel(Stream excelFileStream,
int
sheetIndex,
int
headerRowIndex)
{
HSSFWorkbook workbook
=
new
HSSFWorkbook(excelFileStream);
HSSFSheet sheet
=
workbook.GetSheetAt(sheetIndex);
DataTable table
=
new
DataTable();
HSSFRow headerRow
=
sheet.GetRow(headerRowIndex);
int
cellCount
=
headerRow.LastCellNum;
for
(
int
i
=
headerRow.FirstCellNum; i
<
cellCount; i
++
)
{
if
(headerRow.GetCell(i)
==
null
||
headerRow.GetCell(i).StringCellValue.Trim()
==
""
)
{
//
如果遇到第一个空列，则不再继续向后读取
cellCount
=
i
+
1
;
break
;
}
DataColumn column
=
new
DataColumn(headerRow.GetCell(i).StringCellValue);
table.Columns.Add(column);
}
for
(
int
i
=
(sheet.FirstRowNum
+
1
); i
<=
sheet.LastRowNum; i
++
)
{
HSSFRow row
=
sheet.GetRow(i);
if
(row
==
null
||
row.GetCell(
0
)
==
null
||
row.GetCell(
0
).ToString().Trim()
==
""
)
{
//
如果遇到第一个空行，则不再继续向后读取
break
;
}
DataRow dataRow
=
table.NewRow();
for
(
int
j
=
row.FirstCellNum; j
<
cellCount; j
++
)
{
dataRow[j]
=
row.GetCell(j);
}
table.Rows.Add(dataRow);
}
excelFileStream.Close();
workbook
=
null
;
sheet
=
null
;
return
table;
}
///
<summary>
///
由Excel导入DataTable
///
</summary>
///
<param name="excelFilePath">
Excel文件路径，为物理路径。
</param>
///
<param name="sheetName">
Excel工作表索引
</param>
///
<param name="headerRowIndex">
Excel表头行索引
</param>
///
<returns>
DataTable
</returns>
public
static
DataTable ImportDataTableFromExcel(
string
excelFilePath,
int
sheetIndex,
int
headerRowIndex)
{
using
(FileStream stream
=
System.IO.File.OpenRead(excelFilePath))
{
return
ImportDataTableFromExcel(stream, sheetIndex, headerRowIndex);
}
}
有Excel导入DataSet
代码
///
<summary>
///
由Excel导入DataSet，如果有多个工作表，则导入多个DataTable
///
</summary>
///
<param name="excelFileStream">
Excel文件流
</param>
///
<param name="headerRowIndex">
Excel表头行索引
</param>
///
<returns>
DataSet
</returns>
public
static
DataSet ImportDataSetFromExcel(Stream excelFileStream,
int
headerRowIndex)
{
DataSet ds
=
new
DataSet();
HSSFWorkbook workbook
=
new
HSSFWorkbook(excelFileStream);
for
(
int
a
=
0
, b
=
workbook.NumberOfSheets; a
<
b; a
++
)
{
HSSFSheet sheet
=
workbook.GetSheetAt(a);
DataTable table
=
new
DataTable();
HSSFRow headerRow
=
sheet.GetRow(headerRowIndex);
int
cellCount
=
headerRow.LastCellNum;
for
(
int
i
=
headerRow.FirstCellNum; i
<
cellCount; i
++
)
{
if
(headerRow.GetCell(i)
==
null
||
headerRow.GetCell(i).StringCellValue.Trim()
==
""
)
{
//
如果遇到第一个空列，则不再继续向后读取
cellCount
=
i
+
1
;
break
;
}
DataColumn column
=
new
DataColumn(headerRow.GetCell(i).StringCellValue);
table.Columns.Add(column);
}
for
(
int
i
=
(sheet.FirstRowNum
+
1
); i
<=
sheet.LastRowNum ; i
++
)
{
HSSFRow row
=
sheet.GetRow(i);
if
(row
==
null
||
row.GetCell(
0
)
==
null
||
row.GetCell(
0
).ToString().Trim()
==
""
)
{
//
如果遇到第一个空行，则不再继续向后读取
break
;
}
DataRow dataRow
=
table.NewRow();
for
(
int
j
=
row.FirstCellNum; j
<
cellCount; j
++
)
{
if
(row.GetCell(j)
!=
null
)
{
dataRow[j]
=
row.GetCell(j).ToString();
}
}
table.Rows.Add(dataRow);
}
ds.Tables.Add(table);
}
excelFileStream.Close();
workbook
=
null
;
return
ds;
}
///
<summary>
///
由Excel导入DataSet，如果有多个工作表，则导入多个DataTable
///
</summary>
///
<param name="excelFilePath">
Excel文件路径，为物理路径。
</param>
///
<param name="headerRowIndex">
Excel表头行索引
</param>
///
<returns>
DataSet
</returns>
public
static
DataSet ImportDataSetFromExcel(
string
excelFilePath,
int
headerRowIndex)
{
using
(FileStream stream
=
System.IO.File.OpenRead(excelFilePath))
{
return
ImportDataSetFromExcel(stream, headerRowIndex);
}
}
另外为导入补充一点知识：
1、将Excel的列索引转换为列名，列索引从0开始，列名从A开始。如第0列为A，第1列为B...
代码
///
<summary>
///
将Excel的列索引转换为列名，列索引从0开始，列名从A开始。如第0列为A，第1列为B...
///
</summary>
///
<param name="index">
列索引
</param>
///
<returns>
列名，如第0列为A，第1列为B...
</returns>
public
static
string
ConvertColumnIndexToColumnName(
int
index)
{
index
=
index
+
1
;
int
system
=
26
;
char
[] digArray
=
new
char
[
100
];
int
i
=
0
;
while
(index
>
0
)
{
int
mod
=
index
%
system;
if
(mod
==
0
) mod
=
system;
digArray[i
++
]
=
(
char
)(mod
-
1
+
'
A
'
);
index
=
(index
-
1
)
/
26
;
}
StringBuilder sb
=
new
StringBuilder(i);
for
(
int
j
=
i
-
1
; j
>=
0
; j
--
)
{
sb.Append(digArray[j]);
}
return
sb.ToString();
}
2、当从Excel获取年月日时，会从在一定的问题，应该在一下代码中，可以想到存在的问题，所以我们可以写个方法封装一下：
代码
///
<summary>
///
转化日期
///
</summary>
///
<param name="date">
日期
</param>
///
<returns></returns>
public
static
DateTime ConvertDate(
string
date)
{
DateTime dt
=
new
DateTime();
string
[] time
=
date.Split(
'
-
'
);
int
year
=
Convert.ToInt32(time[
2
]);
int
month
=
Convert.ToInt32(time[
0
]);
int
day
=
Convert.ToInt32(time[
1
]);
string
years
=
Convert.ToString(year);
string
months
=
Convert.ToString(month);
string
days
=
Convert.ToString(day);
if
(months.Length
==
4
)
{
dt
=
Convert.ToDateTime(date);
}
else
{
string
rq
=
""
;
if
(years.Length
==
1
)
{
years
=
"
0
"
+
years;
}
if
(months.Length
==
1
)
{
months
=
"
0
"
+
months;
}
if
(days.Length
==
1
)
{
days
=
"
0
"
+
days;
}
rq
=
"
20
"
+
years
+
"
-
"
+
months
+
"
-
"
+
days;
dt
=
Convert.ToDateTime(rq);
}
return
dt;
}
}
分享一下体会：
其实有了DataSet的导入导出，DataTable就没有必要了，毕竟DataTable组成DataSet，dataSet自动分解为一个个的DataTable，所以一般我用只用DataSet
eg：
代码
//
导出高低温类型产品信息
private
void
btnExportCp_Click(
object
sender, System.EventArgs e)
{
string
sql
=
@"
SELECT CPBM AS 产品编码,CPMC + GGXH AS 产品名称 FROM XS_CPBM WHERE CPLX = '03'AND ZT = '1'
SELECT CPBM AS 产品编码,CPMC + GGXH AS 产品名称 FROM XS_CPBM WHERE CPLX = '06'AND ZT = '1'
"
;
DataSet ds
=
SqlHelper.ExecuteDataset(CommandType.Text,sql);
string
fileName
=
"
高低温产品档案导出.xls
"
;
ExcelHelper.ExportDataSetToExcel(ds,fileName,
"
高温,低温
"
);
}
OK啦，希望对大家有所帮助！